HomeMy WebLinkAboutOrdinance No. 212, 2025
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ORDINANCE NO. 212, 2025
OF THE COUNCIL OF THE CITY OF FORT COLLINS
AMENDING CHAPTER 5, ARTICLE II, DIVISION 2 OF THE CODE
OF THE CITY OF FORT COLLINS FOR THE PURPOSE OF REPEALING THE 2021
INTERNATIONAL ENERGY CONSERVATION CODE AND ADOPTING THE
2024 INTERNATIONAL ENERGY CONSERVATION CODE, WITH AMENDMENTS
A. Since 1924, the City has reviewed, amended and adopted the latest
nationally recognized building standards available for the times; and
B. Upon recommendation of City staff, the City Council has determined that it
is in the best interests of the City to align eleven interconnected basic construction codes
under one publication year; and
C. The eleven interconnected basic construction codes are the International
Building Code, International Residential Code, International Mechanical Code,
International Fuel Gas Code, International Energy Conservation Code, International
Property Maintenance Code, International Swimming Pool and Spa Code, International
Existing Building Code, International Plumbing Code, International Fire Code, and the
International Wildland-Urban Interface Code to the extent adopted by the Colorado
Wildfire Resiliency Code.
D. The City Council has determined that the 2024 publication year of these
interconnected basic construction codes should be adopted and that any counterpart
International codes previously adopted should be repealed, both to align the publication
years of the codes and because the 2024 publications contain improvements in
construction code regulation.
E. City staff has conducted a significant public outreach program, working with
the regulated construction industry and building professionals.
F. The adoption of the interconnected basic construction codes has been
presented to community groups and feedback has been received from the Water
Commission, Energy Board, Commission on Disability, Natural Resource Advisory Board,
Poudre Fire Authority Board, Building Review Commission, Affordable Housing Board,
and Air Quality Advisory Board.
G. The City Council has determined that it is in the best interest of the health,
safety and welfare of the City and its citizens that the 2024 International Energy
Conservation Code be adopted, with local amendments as set forth in this Ordinance.
H. Pursuant to the City Charter Article II, Section 7, City Council may enact
any ordinance which adopts a code by reference in whole or in part provided that before
adoption of such ordinance the Council hold a public hearing thereon and that notice of
the hearing shall be published twice in a newspaper of general circulation published in
the City, with one of such publications occurring at least eight (8) days preceding the
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hearing and the other publication occurring at least fifteen (15) days preceding the
hearing.
I. In compliance with City Charter, Article II, Section 7, the City Clerk
published in the Fort Collins Coloradoan such notice of hearing concerning adoption of
the 2024 International Codes on November 16, 2025, and November 23, 2025.
J. Attached as Exhibit A and incorporated herein by reference is the Notice of
Public Hearing dated November 16, 2025, that was so published and which the Council
hereby finds meets the requirements of Article II, Section 7 of the City Charter.
K. Attached as Exhibit B and incorporated herein by reference is the City of
Fort Collins Building Code Residential Air Tightness Testing Protocol, New Attached and
Detached Single Family Dwellings, dated December 16, 2025, which is referenced in
Paragraph 84 of Section 3 of this Ordinance, regarding IECC Section R402.5.1.2.
L. Attached as Exhibit C and incorporated herein by reference is the City of
Fort Collins New Multifamily Air Tightness Testing Protocol, dated December 16, 2025,
which is referenced in Paragraph 25 of Section 3 of this Ordinance, regarding IECC
Section C402.6.2.2.
In light of the foregoing recitals, which the Council hereby makes and adopts as
determinations and findings, THEREFORE, BE IT ORDAINED BY THE COUNCIL OF
THE CITY OF FORT COLLINS as follows:
Section 1. The City Council hereby repeals the 2021 International Energy
Conservation Code (“IECC”) and adopts the 2024 IECC as amended by this Ordinance.
Section 2. Section 5-26(b) of the Code of the City of Fort Collins is hereby
amended to read as follows:
(b) Pursuant to the power and authority conferred on the City Council by
Colorado Revised Statutes Section 31-16-202 and Article II, Section 7 of the
Charter, the City Council has adopted the 2024 International Energy Conservation
Code published by the International Code Council, first printing (August 2025
update), as amended by the City, which shall have the same force and effect as
though set forth in full herein and which shall apply exclusively to the design and
construction of all buildings that are classified as residential buildings not more
than three (3) stories above grade and their systems; new portions of such existing
buildings and their systems; and new systems and equipment in such existing
buildings, exclusive of detached one- and two-family dwellings, multiple single-
family dwellings (townhouses), for the purpose of establishing minimum
requirements for minimum energy efficiency. As provided in the 2024 International
Energy Conservation Code, Appendices are not adopted except as expressly set
forth in § 5-31.
Section 3. Section 5-31 of the Code of the City of Fort Collins is hereby repealed
and re-enacted to read as follows:
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Sec. 5-31. Amendments and deletions to the 2024 International Energy
Conservation Code.
The 2024 International Energy Conservation Code adopted in § 5-26(b) is amended as
follows:
1. Section C101.1 Title is amended to read as follows:
C101.1 Title. This code shall be known as the Energy Conservation Code of the
City of Fort Collins and shall be cited as such. It is referred to herein as “this code.”
2. Section C102.4 Referenced codes and standards is amended to read as
follows:
C102.4 Referenced codes and standards. The codes and standards referenced
in this code shall be those listed in Chapter 6 of this code and those listed in
Section 101.4 of the adopted International Building Code, entitled “Referenced
Codes,” and such codes and standards shall be considered as p art of the
requirements of this code to the prescribed extent of each such reference and as
further regulated in Sections C102.4.1 and C102.4.2.
3. SECTION C103 CODE COMPLIANCE AGENCY is deleted in its entirety and
replaced with the following:
SECTION C103 CODE ADMINISTRATION
C103.1 Entity charged with code administration. The entity charged with code
administration shall be as determined in accordance with Section 103 of the
adopted International Building Code, entitled “CODE ADMINISTRATION.”
C103.2 Permits. Procedures related to permits, required inspections, payment of
fees and obtaining required approvals shall be as set forth in Chapter 1 of the
adopted International Building Code.
4. Section C105.2 Information on construction documents is amended by adding
at the end the following new items:
. . .
19. Location and size of the solar-ready zone, structural design loads and
roof dead load and roof live load, and pathways for routing of conduit
from the solar-ready zone to the electrical service panel.
20. Locations for condensate drainage where combustion equipment for
space heating and water heating is installed.
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5. SECTION C106 FEES is deleted in its entirety and replaced with the following:
SECTION C106 FEES
C106.1 Fees. All items relating to fees shall be as specified in Section 109 of the
adopted International Building Code, entitled “Fees.”
6. Section C107.2.2 Building thermal envelope is amended to read as follows:
C107.2.2 Building thermal envelope. Inspections shall verify the type of
insulation, R-values, location of insulation, thermal bridge mitigation,
fenestration, U-factor, SHGC and VT, and that air leakage controls are
installed, as required by the code, approved plans and specifications. At the
request of the code official a letter of proof, or intent to contract with an
approved third party air leakage test agency describing the air barrier
inspection sequencing shall be provided to the code official prior to completion
of rough framing or insulation inspections and shall be signed by the building
owner or the building owner’s representative.
7. SECTION C109 MEANS OF APPEALS is deleted in its entirety and replaced with
the following:
SECTION C109 MEANS OF APPEALS
C109.1 Means of appeals. Appeals of decisions, determinations and
interpretations of this code shall be made pursuant to the applicable provisions of
Section 113 of the adopted International Building Code, entitled “MEANS OF
APPEALS.”
8. A new SECTION C111 WAIVERS is added to read as follows:
SECTION C111 WAIVERS
C111.1 Scope. The following waivers shall be permitted to be requested if
buildings meet the requirements of Section C111.2.
C111.2 Buildings Impacted by a Natural Disaster. The code official is permitted
to authorize, upon appeal in specific cases, a waiver from the requirements of
Section C410 where, owing to a declared natural disaster that has destroyed
buildings or resulted in other exceptional and extraordinary circumstances as
determined by the code official, and the code official determines enforcement of
the provisions of Section C410 will result in unnecessary hardship.
9. A new SECTION C112 VIOLATIONS is added to read as follows:
SECTION C112 VIOLATIONS
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C112.1 Violations. Any person who violates a provision of this code or fails to
comply with any of the requirements thereof or who alters or repairs a building or
structure in violation of the approved construction documents or directive of the
code official, or of a permit or certificate issued under the provisions of this code,
commits a civil infraction and is subject to the provisions contained in § 1 -15(f) of
the City Code. Each day that a violation continues shall be deemed a separate
offense.
10. SECTION C202 GENERAL DEFINITIONS is amended to modify or add, in
alphabetical order, the following definitions:
. . .
ALL-ELECTRIC BUILDING. A building that has no natural gas or propane
plumbing installed within the building, and that uses electricity as the sole source
of energy for its space heating and cooling, water heating (including pools and
spas), cooking appliances, and clothes drying appliances. All-electric buildings
may include solar thermal water and pool heating.
. . .
CODE OFFICIAL. The officer or other designated authority charged with the
administration and enforcement of this code, or a duly authorized representative.
The term code official is interchangeable with the term building official.
. . .
COMBUSTION EQUIPMENT. Any equipment or appliance used for space
heating, service water heating, cooking, clothes drying, or lighting that uses fuel
gas or fuel oil.
. . .
CONTINUOUS AIR BARRIER. The combination of interconnected materials,
assemblies, and flexible sealed joints and components of the building thermal
envelope that provides air tightness to a specified permeability.
. . .
CORE AND SHELL. The first phase of a commercial project that has the outer
building envelope constructed and may contain interior lighting and heating and
has not received a permanent Certificate of Occupancy.
. . .
ELECTRIC HEAT. An indoor environmental primary heat source that is a ground-
source electric heat pump or a cold climate heat pump specifically designed to
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heat at the Winter Outdoor, Design Dry-Bulb temperature for Climate Zone 5b as
determined by Section C302.1. The heat pump system shall not be gas or propane
fuel fired.
. . .
FIRST TENANT FINISH. The first build-out of a space in a core and shell that is
credited towards meeting the requirements of this code.
. . .
FUEL GAS. A natural gas, manufactured gas, liquefied petroleum gas, or mixture
of these gases.
FUEL OIL. Kerosene or any hydrocarbon oil having a flash point of not less than
100°F (38°C).
FUTURE ELECTRIC EQUIPMENT. Equipment or appliances necessary to
support future all-electric space heating, water heating, cooking, or clothes drying.
. . .
MULTI ZONE BUILDING. Building or enclosure that consists of more than one
occupancy class or rating separated by a boundary layer designed to control the
movement of air between the different zones.
. . .
11. Section C302.1 Interior design conditions is deleted in its entirety and replaced
with the following:
C302.1 Exterior and interior local design parameters. The following thermal
design parameters, in °F, shall be used for mechanical load calculations and
designs and shall be shown on construction documents:
Winter Outdoor, Design Dry-bulb = 6
Winter Indoor, Design Dry-bulb = 72
Summer, Outdoor Design Dry-bulb = 91
Summer, Indoor Design Dry-bulb = 75
Summer, Outdoor Design Wet-bulb = 62
Summer, Indoor Design Wet-bulb = 62
12. Section C401.2.1 International Energy Conservation Code is amended to read
as follows:
C401.2.1 International Energy Conservation Code. Commercial buildings
shall comply with Appendix CZ and one of the following:
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1. Prescriptive Compliance. The Prescriptive Compliance option requires
compliance with Sections C402 through C406 and Section C408.
Dwelling units and sleeping units in Group R-2 buildings shall be
deemed to be in compliance with this chapter, provided that they comply
with Section R406.
2. Simulated Building Performance. The Simulated Building Performance
option requires compliance with Section C407.
3. Integrated Design Assistance. The Integrated Design Assistance option
requires compliance with Section C411.
Exception: Additions, alterations, repairs and changes of occupancy to
existing buildings complying with Chapter 5.
13. Section C401.2.2 ASHRAE 90.1 is deleted in its entirety.
14. Section C402.1.1.3 Equipment buildings is amended to read as follows, with
item #5 being deleted in its entirety:
C402.1.1.3 Equipment and maintenance buildings. Buildings that
comply with the following shall be exempt from the building thermal
envelope provisions of this code:
1. Are separate buildings with floor area not more than 1,200 square
feet (111 m2).
2. Are intended to house either electric equipment with installed
equipment power totaling not less than 7 watts per square foot (75
W/m2) or maintenance equipment, and are not intended for human
occupancy.
3. Have a heating system capacity not greater than 17,000 Btu/h (5 kW)
and a heating thermostat setpoint that is restricted to not more than
50°F (10°C) and have permanent signage installed at the thermostat
identifying the thermostat setpoint limitation.
4. Have an average wall and roof U-factor less than 0.2 in Climate
Zones 1 through 5 and less than 0.12 in Climate Zones 6 through 8.
15. A new Section C402.1.1.4 Seasonally-occupied restrooms is added to read as
follows:
C402.1.1.4 Seasonally-occupied restrooms. Buildings that comply with
the following shall be exempt from the building thermal envelope provisions
of this code:
1. Are primarily intended for use as restrooms.
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2. Are not intended for occupancy during the period from November
through March.
3. Are separate buildings with floor area not more than 1,200 square
feet (111 m2).
4. Have a heating system capacity not greater than 17,000 Btu/h (5 kW)
and a heating thermostat setpoint that is restricted to not more than
50°F (10°C) and have permanent signage installed at the thermostat
identifying the thermostat setpoint limitation.
5. Have an average wall and roof U-factor less than 0.2.
16. TABLE C402.1.2 OPAQUE BUILDING THERMAL ENVELOPE ASSEMBLY
MAXIMUM REQUIREMENTS, U-FACTOR METHODa,b is deleted in its entirety
and replaced with the following:
TABLE C402.1.2 OPAQUE BUILDING THERMAL ENVELOPE ASSEMBLY MAXIMUM
REQUIREMENTS, U-FACTOR METHODa,b
CLIMATE ZONE 5 All other Group R
Roofs
Insulation entirely
above roof deck U-0.032 U-0.032
Metal buildings U-0.035 U-0.035
Attic and other U-0.021 U-0.021
Walls, above grade
Masse U-0.067 U-0.067
Metal building U-0.049 U-0.049
Metal framed U-0.052 U-0.052
Wood framed and
otheri U-0.046 U-0.046
Walls, below grade
Below-grade wallc C-0.092 C-0.092
Floors
Massd U-0.057 U-0.051
Floor - steel joist U-0.029 U-0.029
Wood joist/framing U-0.027 U-0.027
Slab-on-grade floors
Unheated slabsh F-0.52 F-0.51
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Heated slabs F-0.62 F-0.62
Opaque doors
Non-swinging door U-0.31 U-0.31
Swinging doorf U-0.37 U-0.37
Garage door <14%
glazingg U-0.31 U-0.31
For SI: 1 pound per square foot = 4.88 kg/m2, 1 pound per cubic foot = 16 kg/m3.
a. Where assembly U-factors, C-factors and F-factors are established in ANSI/ASHRAE/IES 90.1 Appendix A, such
opaque assemblies shall be a compliance alternative where those values meet the criteria of this table, and provided
that the construction, excluding the cladding system on walls, complies with the appropriate construction details from
ANSI/ASHRAE/IES 90.1 Appendix A.
b. Where U-factors have been established by testing in accordance with ASTM C1363, such opaque assemblies shall be a
compliance alternative where those values meet the criteria of this table. The R-value of continuous insulation shall be
permitted to be added to or subtracted from the original tested design.
c. Where heated slabs are below grade, below-grade walls shall comply with the U-factor requirements for above-grade
mass walls.
d. “Mass floors” shall be in accordance with Section C402.1.3.4.
e. “Mass walls” shall be in accordance with Section C402.1.3.4.
f. Swinging door U-factors shall be determined in accordance with NFRC-100.
g. Garage doors having a single row of fenestration shall have an assembly U-factor less than or equal to 0.44 in Climate
Zones 0 through 6 and less than or equal to 0.36 in Climate Zones 7 and 8, provided that the fenestration area is not
less than 14 percent and not more than 25 percent of the total door area.
h. Vertical insulation located below grade shall be installed in accordance with Section C402.2.4 and shall be extended the
distance provided in TABLE C402.1.3 or to top of footing.
i. Class 1 vapor retarders shall not be installed on the interior of framed walls where exterior ci value is less than R-7.5.
17. Section C402.1.2.1.8 Mechanical equipment penetrations is deleted in its
entirety.
18. TABLE C402.1.3 OPAQUE BUILDING THERMAL ENVELOPE INSULATION
COMPONENT MINIMUM REQUIREMENTS, R-VALUE METHODa is deleted in
its entirety and replaced with the following:
TABLE C402.1.3
OPAQUE BUILDING THERMAL ENVELOPE INSULATION COMPONENT MINIMUM
REQUIREMENTS, R-VALUE METHODa
CLIMATE ZONE 5 All other Group R
Roofs
Insulation entirely above
roof deck R-30ci R-30ci
Metal buildingsb R-19+R-11 LS R-19+R-11 LS
Attic and other R-49 R-49
Walls, above grade
Massf R13ci R-13ci
Metal building R-13+R-15ci R-13+R-15ci
Metal framed R-13+R-10ci R-13+R-10ci
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Wood framed and otherh,i,j R-15+R-7.5ci or R-20+5ci R-15+R-7.5ci or R-20+5ci
Walls, below grade
Below-grade walld R-10ci R-10ci
Floors
Masse R-14.6ci R-16.7ci
Floor - steel joist R-30+7.5ci R-30+7.5ci
Wood joist/framing R-38 R-38
Slab-on-grade floors
Unheated slabs R-15 for 24” below R-20ci for 24” below
Heated slabsg R-15 for 36” below+R-5 full slab R-15 for 36” below+R-5 full slab
Opaque doors
Opaque non-swinging
doors R-4.75 R-4.75
For SI: 1 inch = 25.4 mm, 1 pound per square foot = 4.88 kg/m2, 1 pound per cubic foot = 16 kg/m3.
ci = Continuous Insulation, NR = No Requirement, LS = Liner System.
a. Assembly descriptions can be found in ANSI/ASHRAE/IESNA 90.1 Appendix A.
b. Where using R-value compliance method, a thermal spacer block shall be provided, otherwise use the U-factor
compliance method in Table C402.1.2.
c. R-5.7ci is allowed to be substituted with concrete block walls complying with ASTM C90, ungrouted or partially
grouted not less than 32 inches on center vertically and not less than 48 inches on center horizontally, with
ungrouted cores filled with materials having a maximum thermal conductivity of 0.44 Btu-in/h-ft2°F.
d. Where heated slabs are below grade, below-grade walls shall comply with the R-value requirements or above-grade
mass walls.
e. “Mass floors” shall be in accordance with Section C402.1.3.4.
f. “Mass walls” shall be in accordance with Section C402.1.3.4.
g. The first value is for perimeter insulation and the second value is for full, under-slab insulation. Perimeter insulation
and full-slab insulation components shall be installed in accordance with Section C402.2.4.
h. The first value is cavity insulation; the second value is continuous insulation. Therefore, “R-0 + R-12ci” means R-12
continuous insulation and no cavity insulation; “R-13 + R-3.8ci” means R-13 cavity insulation and R-3.8 continuous
insulation; “R-20” means R-20 cavity insulation and no continuous insulation. R-13, R-20 and R-27 cavity insulation,
as used in this table, apply to a nominal 4-inch, 6-inch and 8-inch-deep wood or cold-formed steel stud cavities,
respectively.
i. Where the required R-value in Table C402.1.3 is met by using continuous insulation such that cavity insulation is not
required, the R-value is applicable to any wall framing spacing.
j. Class 1 vapor retarders shall not be installed on the interior of framed walls where exterior ci value is less than R-
7.5.
19. Section C402.1.3.3 Suspended ceilings is amended to read as follows:
Section C402.1.3.3 Suspended ceilings. Insulation installed on
suspended ceilings having removable ceiling tiles shall not be considered
part of the minimum thermal resistance (R-value) of roof insulation in roof-
ceiling construction.
Exception: Suspended ceilings with heated plenums over parking
garages where access to mechanical systems is required and that meet
the following criteria:
1. Insulation is a minimum of R-19 and is supported in a permanent
manner by a support no greater than 24 inches on center.
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2. Walls that are part of the building thermal envelope are insulated
in accordance with either Table C402.1.2 or Table C402.1.3.
3. The plenum above the parking garage is heated by a heating
system whose output capacity does not exceed 12 Btu/h for each
square foot.
20. Section C402.2 Specific insulation and installation requirements is amended
to read as follows:
C402.2 Specific insulation and installation requirements. Insulation in building
thermal envelope opaque assemblies shall comply with either Sections C402.2.1
through C402.2.7, or an approved design and Section C402.2.4 Slabs-on-grade.
All insulation shall be installed to meet the requirements of a Grade 1 insulation
installation in accordance with Appendix A of ANSI/RESNET/ICC 301.
21. Section C402.2.4 Slabs-on-grade is amended to read as follows:
C402.2.4 Slabs-on-grade. The perimeter insulation for slab-on-grade shall be
placed on the outside of the foundation or on the inside of the foundation wall
and shall be installed as continuous insulation and without thermal breaks.
Installations shall comply with Table C402.1.3 and the perimeter insulation shall
extend downward from the top of the slab for the minimum distance shown in
the table or to the top of the footing, whichever is less, or downward to not less
than the bottom of the slab and then horizontally to the interior o r exterior for
the total distance shown in the table. Where horizontal sections of insulation
require compressive strength for vehicle traffic and are not greater than eight
inches horizontally, a structural thermal material with an R-value not less than
R-1.8 shall suffice to maintain an installation without thermal breaks. Where
installed, full slab insulation shall be continuous under the entire area of the
slab-on-grade floor, except at structural column locations and service
penetrations. Insulation required at the heated slab perimeter shall not be
required to extend below the bottom of the heated slab and shall be continuous
with the full slab insulation.
Exception: Where the slab-on-grade floor is greater than 24 inches (610
mm) below the finished exterior grade, perimeter insulation is not required.
22. Section C402.6.1 Air barriers is amended to read as follows:
C402.6.1 Air barriers. A continuous air barrier shall be provided throughout
the building thermal envelope. The air barrier is permitted to be located at any
combination of inside, outside or within the building thermal envelope. The air
barrier shall comply with Sections C402.6.1.1 and C402.6.1.2. The air barrier
boundaries and their surface area shall be clearly identified on the approved
construction drawings. If the building within the air barrier boundary is divided
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into zones, the following shall also be clearly identified on the approved
construction drawings:
1. The zone(s);
2. The surface area of each zone; and
3. The zones to be tested for maximum building air infiltration and
exfiltration.
Exception: Air barriers are not required in buildings located in Climate
Zone 2B.
23. Section C402.6.2 Air leakage compliance is amended to read as follows:
C402.6.2 Air leakage compliance. Air leakage of the building thermal
envelope shall be tested by an approved third party air leakage testing agency
in accordance with Section C402.6.2.1. The measured air leakage shall not be
greater than 0.25 cubic feet per minute per square foot (1.2 L/s x m2) of the
building thermal envelope area at a pressure differential of 0.3 inch water
gauge (75 Pa) with the calculated building thermal envelope surface area being
the sum of the above- and below-grade building thermal envelope.
Exceptions:
1. Where the measured air leakage rate is greater than 0.25 cfm/ft2 (1.2
L/s × m2), the approved third party shall perform a diagnostic
evaluation using a smoke tracer, infrared imaging, or acoustic
measurement. The evaluation shall be conducted while the building
is pressurized or depressurized along with a visual inspection of the
air barrier in accordance with ASTM E1186. All identified leaks shall
be sealed and the building shall be re-tested and shall not exceed
the measured air leakage rate specified in this section.
2. As an alternative, buildings or portions of buildings containing Group
I-1 and R-2 occupancies shall be permitted to be tested by an
approved third party air leakage testing agency in accordance with
Section C402.6.2.2. The reported air leakage of the dwelling units or
sleeping units shall not be greater than 0.27 cfm/ft2 (1.4 L/s × m2) of
the testing unit enclosure area at a pressure differential of 0.2 inch
water gauge (50 Pa).
24. Section C402.6.2.1 Whole building test method and reporting is amended to
read as follows:
C402.6.2.1 Whole building test method and reporting. The building
thermal envelope shall be tested by an approved third party in accordance
with ASTM E3158 or an equivalent approved method. A report that includes
the tested surface area, floor area, air by volume, stories above grade, and
air leakage rates shall be submitted to the code official and the building
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owner. The test method shall be a building envelope or operational
envelope test and shall be a multi-point regression, in both pressurization
and depressurization reaching building pressures of 75 Pa, with the results
averaged over a single zone, two or more subsections tested as a single
zone, or a multi zone building.
Exceptions:
. . .
25. Section C402.6.2.2 Dwelling and sleeping unit enclosure method and
reporting is deleted in its entirety and replaced with the following:
C402.6.2.2 Dwelling and sleeping unit enclosure method and
reporting. The building thermal envelope shall be tested in accordance
with ASTM E779, ANSI/RESNET/ICC 380, ASTM E1827 and the City of
Fort Collins New Multifamily Air Tightness Testing Protocol, dated
December 16, 2025 (Ordinance No. 212, 2025). Documentation of the
testing results shall be submitted to the code official prior to approval. If the
building or dwelling unit fails air leakage testing, the testing agency is
required to perform a diagnostic evaluation in accordance with ASTM
E1186. The testing agency can use additional methods to discover leaks.
Corrections based on these diagnostics must be made and the unit must be
re-tested until it meets the required air leakage prior to submitting results to
the code official. The measured air leakage shall not exceed 0.27 cfm/ft2
(1.4 L/s m2) of the testing unit enclosure area at a pressure differential of
0.2 inch water gauge (50 Pa). Units shall be tested separately with an
unguarded blower door test as follows:
1. Where buildings have fewer than eight testing units, each testing
unit shall be tested.
2. For buildings with eight or more testing units, 20 percent of the
testing units in the building shall be tested, including at least one
of each unit type and approximately an equal number of units on
each floor level. For each tested unit that exceeds the maximum
air leakage rate, corrections to the unit must be made and the unit
must be re-tested until it meets the required air leakage, and an
additional two units of this type in the same building shall be
tested and meet the required air leakage.
3. A final inspection report shall be provided for inspections
completed by the registered design professional or approved
agency. The inspection report shall be provided to the building
owner or owner’s authorized agent and the code official. The
report shall identify deficiencies found during inspection and
details of corrective measures taken.
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Exception: Corridors, stairwells, and enclosed spaces, other
than a dwelling unit and sleeping unit, having a conditioned floor
area not greater than 1,500 square feet (139 m2) may
alternatively comply with Section C402.6.2.3 and either Section
C402.6.2.3.1 or Section C402.6.2.3.2.
26. Section C402.6.2.3 Building thermal envelope design and construction
verification criteria is amended to read as follows:
C402.6.2.3 Building thermal envelope design and construction
verification criteria. The installation of the continuous air barrier shall be
verified by the code official and an approved air leakage testing agency in
accordance with the following:
1. A review of the construction documents and other supporting data
shall be conducted to assess compliance with the requirements in
Section C402.6.1.
2. Inspection of continuous air barrier components and assemblies
shall be conducted during construction while the air barrier is still
accessible for inspection and repair to verify compliance with the
requirements of Sections C402.6.2.3.1 and C402.6.2.3.2.
3. An air barrier and air sealing inspection report completed by the
approved air leakage testing agency shall be provided to the building
owner or owner’s authorized agent and the code official at the time
of framing and insulation inspection. The report shall identify
deficiencies found during the review of the construction documents
and inspection and details of corrective measures taken or to be
undertaken.
27. Section C402.6.4 Doors and access openings to shafts, chutes, stairways
and elevator lobbies is amended to read as follows:
C402.6.4 Doors and access openings to shafts, chutes, stairways and
elevator lobbies. Doors and access openings from conditioned space to
shafts, chutes, stairways and elevator lobbies not within the scope of the
fenestration assemblies covered by Section C402.6.3 shall be gasketed,
weather-stripped or sealed. Doors and access openings on vertical walls from
conditioned space to unconditioned attic space shall be insulated to a minimum
of R-7.
Exceptions:
1. Door openings required to comply with Section 716 of the
International Building Code.
2. Doors and door openings required by the International Building Code
to comply with UL 1784.
28. Section C403.4.1.1 Heat pump supplementary heat is amended to read as
follows:
- 15 -
C403.4.1.1 Heat pump supplementary heat. Heat pumps having
supplementary electric resistance heat shall have controls that limit
supplemental heat operation to only those times when outdoor
temperatures are less than or equal to 15°F (-9.4°C) and when one of the
following applies:
1. The vapor compression cycle cannot provide the necessary heating
energy to satisfy the thermostat setting.
2. The heat pump is operating in defrost mode.
3. The vapor compression cycle malfunctions.
4. The thermostat malfunctions.
29. A new Section C403.4.9 Demand response is added to read as follows:
C403.4.9 Demand response.
C403.4.9.1 Demand responsive controls. Electric heating and cooling
systems shall be provided with demand responsive controls capable of
executing the following actions in response to a demand response signal:
1. Automatically increasing the zone operating co oling setpoint by the
following values: 1°F (0.5°C), 2°F (1°C), 3°F (1.5°C) and 4°F (2°C).
2. Automatically decreasing the zone operating heating setpoint by the
following values: 1°F (0.5°C), 2°F (1°C), 3°F (1.5°C) and 4°F (2°C).
Where a demand response signal is not available, the heating and cooling
system controls shall be capable of performing all other functions. Where
thermostats are controlled by direct digital control including, but not limited
to, an energy management system, the system shall be capable of demand
responsive control and capable of adjusting all thermal setpoints to comply.
The demand responsive controls shall comply with either Section
C403.4.9.1.1 or C403.4.9.1.2.
Exceptions:
1. Group I occupancies.
2. Group H occupancies.
3. Controls serving data center systems.
4. Occupancies or applications requiring precision in indoor
temperature control where approved by the code official.
5. Buildings with energy storage capacity for not less than a 25
percent load reduction at peak load for a period of not less
than 3 hours.
30. A new Section C403.4.9.1.1 Air conditioners and heat pumps with two or
more stages of control and cooling capacity of less than 65,000 Btu/h is
added to read as follows:
- 16 -
C403.4.9.1.1 Air conditioners and heat pumps with two or more
stages of control and cooling capacity of less than 65,000 Btu/h.
Thermostats for air conditioners and heat pumps with two or more
stages of control and a cooling capacity less than 65,000 Btu/h (19 kW)
shall be provided with a demand responsive control that complies with
the communication and performance requirements of AHRI 1380.
31. A new Section C403.4.9.1.2 All other heating and cooling systems is added to
read as follows:
C403.4.9.1.2 All other heating and cooling systems. Thermostats for
heating and cooling systems not covered by Section C403.4.9.1.1 shall
be provided with a demand responsive control that complies with one of
the following:
1. Certified OpenADR 2.0a VEN, as specified under Clause 11,
Conformance.
2. Certified OpenADR 2.0b VEN, as specified under Clause 11,
Conformance.
3. Certified by the manufacturer as being capable of responding to
a demand response signal from a certified OpenADR 2.0b VEN
by automatically implementing the control functions requested by
the VEN for the equipment it controls.
4. IEC 62746-10-1.
5. The communication protocol required by a controlling entity, such
as a utility or service provider, to participate in an autom ated
demand response program.
6. The physical configuration and communication protocol of
ANSI/CTA 2045-A or ANSI/CTA 2045-B.
32. Section C403.13.3.1 Protection of piping insulation is amended to read as
follows:
C403.13.3.1 Protection of piping insulation. Piping insulation exposed to
the weather shall be protected from physical damage, including that caused
by sunlight, moisture, equipment maintenance and wind . The protection
shall provide shielding from solar radiation that can cause degradation of
the material. The protection shall be removable and reusable for not less
than 6 inches (152 mm) from the connection to the equipment piping for
maintenance. Adhesive tape, paint products applied to HVAC system
insulating materials, and other similar applications that require maintenance
shall not be permitted as a means of insulation protection.
33. A new Section C404.10 Demand responsive water heating and TABLE
C404.10 DEMAND RESPONSIVE CONTROLS FOR WATER HEATING are
added to read as follows:
- 17 -
C404.10 Demand responsive water heating. Electric storage water heaters with
a rated water storage volume of 40 gallons (151 L) to 120 gallons (454 L) and a
nameplate input rating equal to or less than 12 kW shall be provided with demand
responsive controls in accordance with Table C404.10 or another equivalent
approved standard.
Exceptions:
1. Water heaters that provide a hot water delivery temperature of 180°F
(82°C) or greater.
2. Water heaters that comply with Section IV, Part HLW or Section X of
the ASME Boiler and Pressure Vessel Code.
3. Water heaters that use 3-phase electric power.
TABLE C404.10
DEMAND RESPONSIVE CONTROLS FOR WATER HEATING
Equipment Type
Standards Applicable to Controls
Manufactured Before 7/1/2025 Manufactured On or After
7/1/2025
Electric storage
water heaters
AHRI Standard 1430 or
ANSI/CTA-2045-B Level 1 and
also capable of initiating water
heating to meet the temperature
set point in response to a demand
response signal.
ANSI/CTA-2045-B Level 2,
except “Price Stream
Communication”
functionality as defined in the
standard.
34. Section C405.2.7.1 Daylight shutoff is amended to read as follows:
C405.2.7.1 Daylight shutoff. Lights shall be automatically turned off within
30 minutes after sunrise if daylight is present.
35. Section C405.2.7.3 Lighting setback is amended to read as follows:
C405.2.7.3 Lighting setback. Lighting that is not controlled in accordance
with Section C405.2.7.2 shall comply with the following:
1. Be controlled so that the total wattage of such lighting is
automatically reduced by not less than 50 percent by selectively
switching off or dimming luminaires at one of the following times:
1.1. From not later than 1 hour after building or business closing to
not earlier than 1 hour before building or business opening.
1.2. During any time where activity has not been detected for 15
minutes or more.
2. Luminaires serving exterior parking areas shall be controlled so that
the total wattage of such lighting is automatically reduced by not less
than 50 percent during any time where activity has not been detected
- 18 -
for 15 minutes or more. Not more than 1,500 watts of lighting power
shall be controlled together.
36. Section C405.2.9 Interior parking area lighting control is amended to read as
follows, with the exception to item #1 being deleted in its entirety:
C405.2.9 Interior parking area lighting control. Interior parking area lighting
shall be controlled by an occupant sensor complying with Section C405.2.1.1
or a time-switch control complying with Section C405.2.2.1. Additional lighting
controls shall be provided as follows:
1. Lighting power of each luminaire shall be automatically reduced by not
less than 50 percent when there is no activity detected within a lighting
zone for 15 minutes.
. . .
37. Section C405.3.3 Lighting power for sleeping units and dwelling units is
amended to read as follows:
C405.3.3 Lighting power for sleeping units and dwelling units . Sleeping
units in Group I-2 occupancies that are patient rooms shall comply with
Sections C405.3.1 and C405.3.2. For all other sleeping units and dwelling units,
permanently installed lighting, including lighting integrated into range hoods
and exhaust fans, shall be provided by lamps capable of operating with an
efficacy of not less than 65 lumens per watt or luminaires capable of operating
with an efficacy of not less than 45 lumens per watt. Sleeping units shall have
control devices or systems that are configured to automatically switch off all
permanently installed luminaires, switched receptacles, televisions, and to
adjust the heating, ventilating and air conditioning system set point by raising it
at least 5°F (3°C) in the cooling mode and lowering it at least 5°F (3°C) in the
heating mode whenever the sleeping unit is unoccupied. All permanently wired
luminaires located in bathrooms within sleeping units shall be equipped with
occupant sensors that require manual intervention to energize circuits.
Exceptions:
1. Lighting integral to other appliances.
2. Antimicrobial lighting used for the sole purpose of disinfecting.
3. Luminaires with an input rating of less than 3 watts.
4. Lighting and switched receptacles controlled by card key controls.
5. Existing buildings undergoing an occupancy change to R-1 and that
have no more than 8 sleeping units.
38. Section C405.13 Energy monitoring is amended to read as follows:
- 19 -
C405.13 Energy monitoring. New buildings with greater than or equal to 600 amp
electric service shall be equipped to measure, monitor, record and report energy
consumption data in accordance with Sections C405.13.1 through C405.13.6 for
load categories indicated in Table C405.13.2 and Sections C405.13.7 through
C405.13.11 for end-use categories indicated in Table C405.13.8.
Exceptions:
1. Dwelling units in R-2 occupancies.
2. Individual tenant spaces are not required to comply with this section
provided that the space has its own utility services and meters and
has less than 5,000 square feet (464.5 m2) of conditioned floor area.
39. Section C405.15 Renewable energy systems and all of Sections C405.15.1
through C405.15.4 are deleted in their entirety.
40. Section C406.1.1 Additional energy efficiency credit requirements is
amended to read as follows:
C406.1.1 Additional energy efficiency credit requirements . Buildings shall
comply with measures from Section C406.2 to achieve not less than the
number of required efficiency credits from Table C406.1.1(1) based on building
occupancy group and climate zone. Where a project contains multiple
occupancies, the total required energy credits from each building occupancy
shall be weighted by the gross conditioned floor area to determine the
weighted-average project energy credits required. Accessory occupancies
shall be included with the primary occupancy group for the purposes of Section
C406. All buildings shall also comply with Section C406.1.1.3.
Exceptions:
. . .
41. A new Section C406.1.1.3 Limit on energy credits from renewable energy and
TABLE C406.1.1.3 LIMITS ON ENERGY CREDITS FROM RENEWABLE
ENERGY are added to read as follows:
C406.1.1.3 Limit on energy credits from renewable energy. For
buildings utilizing renewable energy in accordance with energy credit ID
R01 to achieve the required energy credits required in either Section
C406.1.1.1 or Section C406.1.1.2, the number of energy credits achieved
through renewable energy shall not exceed the limits in Table C406.1.1.3.
TABLE C406.1.1.3 LIMITS ON ENERGY CREDITS FROM RENEWABLE
ENERGY
- 20 -
Building Occupancy Group Maximum Renewable Energy Credits
Allowed
R-2, R-4, and I-1 5
I-2 26
R-1 37
B 35
A-2 5
M 5
E 32
S-1 and S-2 35
All Other 6
42. Section C406.1.2 Additional renewable and load management credit
requirements is deleted in its entirety.
43. Section C406.2 Additional energy efficiency credits achieved is deleted in its
entirety and replaced with the following:
C406.2 Additional energy credits achieved. Energy credit measures shall
achieve credits as follows:
1. Each energy credit measure from the energy efficiency category (energy
credit ID E01-E06, H01-H05, W01-W10, P01, L01-L06, and Q01-Q04) used
to meet credit requirements for the project shall have efficiency that is
greater than the requirements in Sections C402 through C405.
2. Energy credit measures in the renewable energy and load management
category in Sections C406.2.9 through C406.2.13 (energy credit ID G01 -
G05) require load management and control sequences shall be capable of
and configured to automatically provide the load management operation
specified based on indication of a peak period related to high short -term
electric prices, grid condition, or peak building load. A peak period shall be
initiated by a demand response signal from the controlling entity, such as a
utility or service operator. Where communications are disabled or
unavailable, all demand-responsive controls shall continue backup demand
response based on a local schedule or building-demand monitoring. The
local building schedule shall be adjustable without programming and reflect
the electric rate peak period dates and times. The load management control
sequences shall be activated for peak period control by one of the following:
2.1 A certified OpenADR 2.0a or OpenADR 2.0b Virtual End Node
(VEN), as specified under Clause 11, Conformance, in the applicable
OpenADR 2.0 Specification.
2.2 A device certified by the manufacturer as being capable of
responding to a demand response signal from a certified OpenADR
2.0b VEN by automatically implementing the control fun ctions
requested by the VEN for the equipment it controls.
- 21 -
2.3 The physical configuration and communication protocol of
ANSI/CTA-2045-A or ANSI/CTA-2045-B.
2.4 For air conditioners and heat pumps with two or more stages of
control and cooling capacity of less than 65,000 Btu/h (19 kW),
thermostats with a demand responsive control that complies with the
communication and performance requirements of AHRI 1380.
2.5 A device that complies with IEC 62746-10-1.
2.6 An interface that complies with the communication protocol requi red
by a controlling entity to participate in an automated demand
response program.
2.7 Where the controlling entity does not have a demand response signal
available for the building type and size, local load management
control shall comply with one of the following:
2.7.1 Building demand management controls that monitor building
electrical demand and initiate controls to minimize monthly or
peak time period demand charges.
2.7.2 A local building schedule that reflects the electric rate peak
period dates and times where buildings are less than 25,000
gross square feet (2322 m²).
A binary input to the control system shall be provided that activates the
demand response sequence.
3. Measures installed in the project that meet the requirements in Sections
C406.2.1 through C406.2.16 shall achieve the base credits listed for the
measure and occupancy type in Tables C406.2(1) through C406.2(9) or,
when calculations are required by Sections C406.2.1 through C406.2.16
create or modify the credits from Tables C406.2(1) through C406.2(9 ), the
credits achieved shall be based on the calculations. Energy credits
achieved for measures shall be determined by one of the following, as
applicable:
3.1 The measure’s energy credit shall be the base energy credit from
Tables C406.2(1) through C406.2(9) for the measure where no
adjustment factor or calculation is included in the description of the
measure in Section C406.2.
3.2 The measure’s energy credit shall be the base energy credit for the
measure adjusted by a factor or equation as stated in the description
of the measure in Section C406.2. Where adjustments are applied,
each measure’s energy credit shall be rounded up to the nearest
whole number.
3.3 The measure’s energy credit shall be calculated in accordance with
the measure’s description in Section C406.2. Each individual
measure credit shall be rounded up to the nearest whole number.
- 22 -
4. Energy credits achieved for the project shall be the sum of the individual
measures’ energy credits. Where a project contains multiple building
occupancy groups:
4.1 Credits achieved for each occupancy group shall be summed and
then weighted by the conditioned floor area of each occupancy group
to determine the weighted average project energy credits achieved.
4.2 Improved envelope efficiency (energy credit ID E01 through E06),
HVAC performance (energy credit ID H01), and lighting reduction
(energy credit ID L06) measure credits shall be determined for the
building or permitted conditioned floor area as a whole. Credits for
other measures shall be determined for each occupancy separately.
Credits shall be taken from applicable tables or calculations for each
occupancy and weighted by the building occupancy group floor area.
44. TABLE C406.2(1) BASE ENERGY CREDITS FOR GROUP R-2, R-4 AND I-1
OCCUPANCIESa is amended by adding two rows to read as follows:
TABLE C406.2(1) BASE ENERGY CREDITS FOR GROUP R-2, R-4 AND
I-1 OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
45. TABLE C406.2(2) BASE ENERGY CREDITS FOR GROUP I-2 OCCUPANCIESa
is amended by adding two rows to read as follows:
TABLE C406.2(2) BASE ENERGY CREDITS FOR GROUP I-2
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
46. TABLE C406.2(3) BASE ENERGY CREDITS FOR GROUP R-1 OCCUPANCIESa
is amended by adding two rows to read as follows:
- 23 -
TABLE C406.2(3) BASE ENERGY CREDITS FOR GROUP R-1
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
47. TABLE C406.2(4) BASE ENERGY CREDITS FOR GROUP B OCCUPANCIESa
is amended by adding two rows to read as follows:
TABLE C406.2(4) BASE ENERGY CREDITS FOR GROUP B
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
48. TABLE C406.2(5) BASE ENERGY CREDITS FOR GROUP A-2 OCCUPANCIESa
is amended by adding two rows to read as follows:
TABLE C406.2(5) BASE ENERGY CREDITS FOR GROUP A-2
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
49. TABLE C406.2(6) BASE ENERGY CREDITS FOR GROUP M OCCUPANCIESa
is amended by adding two rows to read as follows:
TABLE C406.2(6) BASE ENERGY CREDITS FOR GROUP M
OCCUPANCIESa
ID Section Climate Zone
- 24 -
Energy Credit
Measure
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
50. TABLE C406.2(7) BASE ENERGY CREDITS FOR GROUP E OCCUPANCIESa
is amended by adding two rows to read as follows:
TABLE C406.2(7) BASE ENERGY CREDITS FOR GROUP E
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
51. TABLE C406.2(8) BASE ENERGY CREDITS FOR GROUP S-1 AND S-2
OCCUPANCIESa is amended by adding two rows to read as follows:
TABLE C406.2(8) BASE ENERGY CREDITS FOR GROUP S-1 AND S-2
OCCUPANCIESa
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
52. TABLE C406.2(9) BASE ENERGY CREDITS FOR OTHER OCCUPANCIESa,b is
amended by adding two rows to read as follows:
TABLE C406.2(9) BASE ENERGY CREDITS FOR OTHER
OCCUPANCIESa,b
ID Energy Credit
Measure Section
Climate Zone
. . . 5B . . .
- 25 -
. . . . . . . . . . . . . . . . . .
R01 Renewable energy C406.3.1 . . . 11 . . .
O01 Refrigerants C406.2.16 . . . 2 . . .
. . . . . . . . . . . . . . . . . .
53. A new Section C406.3.1.1 Off-site renewable energy is added to read as follows:
C406.3.1.1 Off-site renewable energy. Buildings that procure off-site
renewable energy shall comply with Sections C406.3.1.1.1 through
C406.3.1.1.3.
54. A new Section C406.3.1.1.1 Off-site renewable energy requirements and
TABLE C406.3.1.1.1(1) ANNUAL OFF-SITE RENEWABLE ENERGY
REQUIREMENTS are added to read as follows:
C406.3.1.1.1 Off-site renewable energy requirements. Off-site
renewable energy shall be procured in accordance with Table
C406.3.1.1.1(1).
TABLE C406.3.1.1.1(1) ANNUAL OFF-SITE RENEWABLE ENERGY REQUIREMENTS
Climate Zone Annual Off-Site Renewable Electrical Energy (kWh/W)a
5B 1.75
a. Annual off-site renewable energy systems with 1.35 kWh/W to 1.75 kWh/W renewable electrical
energy shall be reduced to 9 credits in TABLES C406.2(1), (2), (3), (4), (5), (6), (7), (8), (9). Systems
with less than 1.35 kWh/W renewable electrical energy shall receive 0 credits.
55. A new Section C406.3.1.1.2 Off-site procurement is added to read as follows:
C406.3.1.1.2 Off-site procurement. The building owner, as defined in
the adopted International Building Code, shall be credited for the total
amount of off-site renewable electrical energy procured with one or more
of the following:
1. Physical renewable energy power purchase agreement.
2. Financial renewable energy power purchase agreement.
3. Community renewable energy facility.
4. Off-site renewable energy system owned by the building owner.
5. Renewable energy investment fund.
6. Green retail tariff.
The generation source for off-site renewable electrical energy shall be
located where the energy can be delivered to the building site by any of
the following:
1. Direct connection to the off-site renewable energy facility.
- 26 -
2. The local utility or distribution entity.
3. An interconnected electrical network where energy delivery
capacity between the generator and the building site is available.
56. A new Section C406.3.1.1.3 Off-site contract is added to read as follows:
C406.3.1.1.3 Off-site contract. The renewable energy shall be
delivered or credited to the building site under an energy contract with a
duration of not less than 15 years. The contract shall be structured to
survive a partial or full transfer of ownership of the building property.
57. A new Section C406.3.9 O01 Refrigerants and TABLE C406.3.9 ENERGY
CREDIT ADJUSTMENT FOR REFRIGERANT GWP LEVEL are added to read as
follows:
C406.3.9 O01 Refrigerants. Projects that select equipment for space heating
and service water heating that utilize low global warming potential (GWP) or
ultra-low GWP refrigerants may receive energy credits for this measure
calculated as follows:
Equation 4-34 ECO01_ach = ECO01_base x ECO01_adj
where:
ECO01_ach = Refrigerant credit achieved for the project.
ECO01_base = O01 base energy credit from Tables C406.2(1) through
C406.2(9).
ECO01_adj = Energy credit adjustment factor from Table C406.2.16.
TABLE C406.3.9 ENERGY CREDIT ADJUSTMENT FOR REFRIGERANT
GWP LEVEL
Refrigerant Category GWP Limit (kgCO2e) ECO01_adj
Ultra-low GWP < 10 100%
Low GWP 10 to 50 50%
Other > 150 0%
58. Section C407.2 Mandatory requirements is amended to read as follows:
C407.2 Mandatory requirements. Compliance based on simulated building
performance requires that a proposed design meet all the following:
1. The requirements of the sections indicated within Table C407.2(1)
2. The requirements of CZ103.1.
- 27 -
59. TABLE C407.2(1) REQUIREMENTS FOR SIMULATED BUILDING
PERFORMANCE is amended to read as follows:
TABLE C407.2(1)
REQUIREMENTS FOR SIMULATED BUILDING PERFORMANCE
SECTIONa TITLE
Envelope
. . . . . .
C402.2.4 Slabs-on-grade
. . . . . .
Other
C410 Electric Ready, and Solar Ready
. . . . . .
59. TABLE C407.4.1(1) SPECIFICATIONS FOR THE STANDARD REFERENCE
AND PROPOSED DESIGNS is amended to read as follows:
TABLE C407.4.1(1) SPECIFICATIONS FOR THE STANDARD
REFERENCE AND PROPOSED DESIGNS
BUILDING COMPONENT
CHARACTERISTICS STANDARD REFERENCE DESIGN PROPOSED DESIGN
. . . . . . . . .
On-site renewable energy On-site renewable energy shall not be
included in the standard reference design. As proposed
. . . . . . . . .
60. Section C408.2 Mechanical systems and service water-heating systems
commissioning and completion requirements is amended to read as follows:
C408.2 Mechanical systems and service water -heating systems
commissioning and completion requirements.
. . .
Exceptions: The following systems are exempt:
1. Buildings with less than 10,000 square feet (929 m2) gross conditioned
floor area.
2. Systems included in Section C403.5 that serve individual dwelling units
and sleeping units.
61. Section C408.2.5.2 Final commissioning report is amended to read as follows:
C408.2.5.2 Final commissioning report. A report of test procedures and
results identified as “Final Commissioning Report” shall be delivered to the
building owner or owner’s authorized agent and shall be made available to
- 28 -
the code official upon request. The report shall be organized with
mechanical system and service hot water system findings in separate
sections to allow independent review. The report shall include the following:
1. Results of functional performance tests.
2. Disposition of deficiencies found during testing, including details of
corrective measures used.
3. Functional performance test procedures used during the
commissioning process including measurable criteria for test
acceptance, provided herein for repeatability.
Exception: Deferred tests that cannot be performed at the time of report
preparation due to climatic conditions.
62. A new SECTION C410 ELECTRIC READY AND SOLAR READY is added to read
as follows:
SECTION C410 ELECTRIC READY AND SOLAR READY
C410.1 Scope. This section establishes requirements for electric readiness, solar
readiness, and electric vehicle (EV) readiness in commercial buildings.
C410.2 Compliance. Commercial buildings shall comply with Sections C410.3
through C410.5.
C410.3 Electric ready.
C410.3.1 General. The provisions of Section C410.3 shall apply to all new
buildings, additions, and first tenant finish permits.
C410.3.1.1 First tenant finishes. In the case that a first tenant finish to a
commercial core and shell building or unfinished space is used to satisfy
any requirements of Section C410.3, the code official shall not issue a
Certificate of Occupancy to the tenant until the requirements of Section
C410.3.2 are met.
C410.3.2 Additional electric infrastructure. Combustion equipment in
commercial buildings shall meet the electric infrastructure requirements of
Sections C410.3.2.1 or C410.3.2.2.
Exceptions:
1. Interior fireplaces that do not serve as a primary source of heating.
2. Exterior fireplaces and fire pits.
3. Additions to buildings that do not provide new space heating
equipment shall not be required to provide additional electrical
infrastructure to the existing space heating equipment.
- 29 -
C410.3.2.1 Commercial building less than 10,000 square feet and all R-
occupancies. Commercial buildings that have a gross floor area of less
than 10,000 square feet (929 m2), and all Group R-2, R-3, and R-4
occupancies four stories or greater in height above grade plane, shall
comply with Sections C410.3.2.1.1 through C410.3.2.1.5.
C410.3.2.1.1 Combustion equipment. Combustion equipment shall be
provided with all of the following:
1. A dedicated, appropriately phased branch circuit sized to
accommodate future electric equipment or appliances.
1.1 Electrical infrastructure serving future electric space heating
shall comply with Section C410.3.2.1.1.1.
1.2 Electrical infrastructure serving future electrical water
heating equipment shall comply with Section
C410.3.2.1.1.2.
1.3 Electrical infrastructure serving future electric cooking
equipment or clothes drying equipment shall be sized to
serve a comparable capacity to meet the equipment load in
accordance with the National Electrical Code.
2. An electric receptacle or junction box that meets the requirements
of Section C410.3.2.1.4 and is connected to the electrical panel
through the branch circuit. Each electrical receptacle or junction
box shall have reasonable access to the combustion equipment
or dedicated physical space for future electric equipment with no
obstructions other than the current combustion equipment.
Exception: Conduit installed with a pull string to a location of
a future transformer or future electrical panel with service size
determined at the time of a future permit.
3. Where combustion equipment is used for space or water heating,
dedicated physical space shall be provided for all future electric
equipment, including an electric resistance backup coil for ducted
systems. Physical space occupied by existing combustion
equipment shall be permitted to count towards satisfying the
physical space requirement, where approved by the code official.
Exception: Buildings with installed air conditioning systems
shall not be required to provide additional dedicated physical
space for an outdoor heat pump.
- 30 -
C410.3.2.1.1.1 Space heating electric infrastructure sizing.
Electric infrastructure for future electric space heating equipment
shall be sized to accommodate at least one of the following:
1. An electrical capacity not less than the nameplate space
heating combustion equipment heating capacity multiplied by
the value in Table C410.3.2.1.1.1, in accordance with
Equation 4-39.
Equation 4-39 VAs = Qcom × Ps
where:
VAs = The required electrical capacity of the electrical
infrastructure in volt-amps.
Qcom = The nameplate heating capacity of the combustion
equipment in kBtu/h.
Ps = The VA per kBtu/h from Table C410.3.2.1.1.1 in
VA/kBtu/h.
2. An electrical capacity not less than the peak space heating
load of the building areas served by the space heating
combustion equipment, calculated in accordance with Section
C403.1.1, multiplied by the value for the 99.6 percent design
heating temperature in Table C410.3.2.1.1.1, in accordance
with Equation 4-40.
Equation 4-40 VAs = Qdesign × Ps
where:
VAs = The required electrical capacity of the electrical
infrastructure in volt-amps.
Qdesign = The 99.6 percent design heating load of the
spaces served by the combustion equipment in kBtu/h.
Ps = The VA per kBtu/h from Table C410.3.2.1.1.1 in
VA/kBtu/h.
3. An approved alternate design that uses no energy source
other than electricity or on-site renewable energy.
- 31 -
TABLE C410.3.2.1.1.1 ALTERNATE ELECTRIC SPACE
HEATING EQUIPMENT CONVERSION FACTORS (VA/kBtu/h)
99.6% Heating Design Temperature Ps
Temperature Range (°F) VA / kBtu/h
>50 N/A
>45 and ≤50 94
>40 and ≤45 100
>35 and ≤40 107
>30 and ≤35 115
>25 and ≤30 124
>20 and ≤25 135
>15 and ≤20 149
>10 and ≤15 164
>5 and ≤10 184
>0 and ≤5 210
>-5 and ≤0 243
>-10 and ≤-5 289
>-15 and ≤-10 293
C410.3.2.1.1.2 Water heating electric infrastructure sizing. An
individual 240-volt branch circuit with an ampacity of not less than 30
shall be provided for future electric water heating equipment with a
capacity of not more than 75,000 Btu/h (22 kW). Electric
infrastructure for future electric water heating equipment with a
capacity of greater than 75,000 Btu/h (22 kW) shall be sized to
accommodate one of the following:
1. An electrical capacity not less than the combustion equipment
water heating capacity multiplied by the value in Table
C410.3.2.1.1.2 plus electric capacity to serve recirculating loads
as shown in Equation 4-41.
Equation 4-41 VAw = (Qcapacity × Pw) + [Qrecirc × 293(VA/(Btu/h))]
where:
VAw = The required electrical capacity of the electrical
infrastructure in volt-amps.
Qcapacity = The nameplate heating capacity of the combustion
equipment in kBtu/h.
Pw = The VA per kBtu/h from Table C410.3.2.1.1.2 in
VA/kBtu/h.
- 32 -
2. An alternate design that complies with this code, where approved
by the code official, and uses no energy source other than
electricity or on-site renewable energy.
TABLE C410.3.2.1.1.2 ALTERNATE ELECTRIC WATER
HEATING EQUIPMENT CONVERSION FACTORS (VA / kBtu/h)
99.6% Heating Design Temperature Ps
Temperature Range (°F) VA / kBtu/h
>55 and ≤60 118
>50 and ≤55 123
>45 and ≤50 129
>40 and ≤45 136
>35 and ≤40 144
>30 and ≤35 152
>25 and ≤30 162
>20 and ≤25 173
>15 and ≤20 185
>10 and ≤15 293
>5 and ≤10 293
>0 and ≤5 293
≤0 293
C410.3.2.1.2 Electric panel space. The electrical panel shall have
reserved physical space for a minimum two-pole or three-pole circuit
breaker for each branch circuit provided for future electric equipment or
appliances. The physical space in the electrical panel for each circuit
breaker shall be sized with sufficient breaker cap acity to meet the
electrical demand of the future electric equipment or appliance that is
sized to serve a comparable capacity to meet the heating load.
C410.3.2.1.3 Labeling. The junction box or receptacle and the
dedicated circuit breaker space serving future electric equipment or
appliances in the electrical panel shall be labeled for their intended use.
C410.3.2.1.4 Adjacency. The electrical receptacle or junction box shall
be provided within 3 feet of the combustion equipment or appliances or
within 3 feet of the dedicated physical space for future electric
equipment or appliances.
Exception: For combustion equipment dedicated to space or
water heating, the electrical receptacle or junction box shall be
located not more than 6 feet from the combustion equipment or the
dedicated physical space for future electric equipment.
- 33 -
C410.3.2.1.5 Condensate drain. Where combustion equipment
dedicated to space heating and water heating is installed, a location
shall be provided for condensate drainage.
C410.3.2.2 Commercial buildings 10,000 square feet or greater. All
commercial buildings that have a gross floor area of 10,000 square feet (929
m2) or greater shall comply with Sections C410.3.2.2.1 through
C410.3.2.2.5.
Exception: Group R-2, R-3, R-4 occupancies four stories or greater in
height above grade plane shall comply with Section C410.3.2.1.
C410.3.2.2.1 Combustion equipment. Combustion equipment shall be
provided with all of the following:
1. A junction box that is located in the same physical space as the
combustion equipment, reasonably accessible, and connected to
the electrical panel by continuous conduit and/or raceways.
2. Dedicated electrical panel space for an appropriately phased
branch circuit sized to accommodate future electric equipment or
appliances.
2.1. Electrical capacity sizing for future electric space heating
equipment shall comply with Section C410.3.2.1.1.1.
2.2. Electrical capacity sizing for future electric water heating
equipment shall comply with Section C410.3.2.1.1.2.
2.3. Electrical infrastructure serving future electric cooking
equipment or clothes drying equipment shall be sized to
serve a comparable capacity to meet the equipment load
in accordance with the National Electrical Code.
3. Where combustion equipment is used for space and water
heating, dedicated physical space shall be provided for all future
electric equipment. Physical space occupied by existing
combustion equipment shall be permitted to count towards
satisfying the physical space requirement, where approved by the
code official.
C410.3.2.2.2 Electrical panel space. The electrical panel shall have
reserved physical space for a minimum two-pole or three-pole circuit
breaker for each branch circuit provided for future electric equipment or
appliances. The physical space in the electrical panel for each circuit
breaker shall be sized with sufficient breaker capacity to meet the
electrical demand of the future electric equipment or appliance that is
sized to serve a comparable capacity to meet the heating load.
- 34 -
C410.3.2.2.3 Labeling. The dedicated circuit breaker space serving
future electric equipment or appliances in the electrical panel shall be
labeled “For future electric equipment.”
C410.3.2.2.4 Physical space. Dedicated physical space shall be
provided for additional electric equipment, including but not limited to
transformers and cabinets, necessary for electrical service to future
electric equipment or appliances.
C410.4 Solar ready.
C410.4.1 General. The provisions of Section C410.4 shall apply to new
buildings, and major renovations and additions.
C410.4.2 Solar-ready zone. A solar-ready zone shall be located on the roof of
all new commercial buildings that are oriented between 110 and 270 degrees
of true north or have low-sloped roofs. Solar-ready zones shall comply with
Sections C410.4.2.1 through C410.4.2.6.
Exceptions:
1. A building with a permanently-installed, on-site renewable energy
system that meets the following criteria:
1.1 The system produces the energy output equivalent to covering
40 percent of the net roof area with solar photovoltaic calculated
as the horizontally projected gross roof area less that area
covered by skylights, occupied roof decks, vegetative roof
areas, and mandatory access or setback areas required by the
International Fire Code.
1.2 The system is located on the roof or overhang of the building or
another structure located within 250 feet of the building, on the
building premises, on covered parking, or another approved
location installed with the building project and under the same
property ownership.
2. A building with a solar-ready zone that is shaded for more than 70
percent of daylight hours annually.
3. A building where a licensed design professional certifies that the
incident solar radiation available to the building is not suitable for a
solar-ready zone.
4. A building where a licensed design professional certifies that the
solar-ready zone area required by Section C410.4.4 cannot be met
because of extensive rooftop equipment, skylights, vegetative roof
areas, or other obstructions.
- 35 -
C410.4.2.1 Construction document requirements for a solar-ready
zone. Construction documents shall indicate the solar-ready zone.
C410.4.2.1.1 Roof loads and documentation. The structural design
loads for roof dead load and roof live load shall be indicated on the
construction documents.
C410.4.2.1.2 Interconnection pathway. Construction documents shall
indicate at least one potential pathway for routing of conduit and/or
raceway from the solar-ready zone to an electrical service panel, which
shall be labeled as “Potential Pathway” on the construction documents.
C410.4.2.2 Solar-ready zone area. The total solar-ready zone area shall
be at least 40 percent of the roof area calculated as the horizontally
projected gross roof area less the area covered by skylights, occupied roof
decks, vegetative roof areas, and mandatory access or set back areas
required by the International Fire Code. The solar-ready zone shall be a
single area or smaller, separated sub-zone areas. For sloped roofs, each
sub-zone area shall be at least 200 square feet (18.6 m2), and the sides of
each rectangular area shall be at least 11 feet (3.35 m) in length. For low-
sloped or flat roofs, each sub-zone area shall be at least 330 square feet
(30.7 m2), with a minimum length running generally north to south of 15 feet
(4.57 m) and a minimum length running generally east to west of 22 feet
(6.7 m), and the sides of each rectangular area shall be at least 11 feet
(3.35 m) in length.
The solar-ready zone shall be located on the roof or overhang of the building
or another structure located within 250 feet of the building, on the building
premises, on covered parking, or another approved location installed with
the building project and under the same property ownership.
C410.4.2.3 Obstructions. Solar-ready zones shall be free from
obstructions, including pipes, vents, ducts, HVAC equipment, skylights, and
roof-mounted equipment.
C410.4.2.6 Electrical service reserved space. The main electrical service
panel shall have a minimum bus bar rating of at least 200 amps. The main
electrical service panel shall have a reserved space to allow installation of
a dual-pole circuit breaker for future solar electric. This space shall be
labeled “For Future Solar Electric.” The reserved space shall be positioned
at the end of the panel that is opposite from the panel supply conductor
connection.
C410.4.3 Commercial solar panel capacity.
- 36 -
C410.4.3.1 General. The provisions of Section C410.4.3 shall apply to new
buildings, and major renovations and additions.
C410.4.3.2 Electric service reserved space. The main electrical service
panel shall have a minimum bus bar rating of at least 200 amps. The main
electrical service panel shall have sufficient reserved space to allow
installation of a dual pole circuit breaker for future solar electric installation
and the reserved space shall be labeled “For Future Solar Electric.” The
reserved space shall be positioned at the opposite (load) end from the input
feeder location or main circuit location.
Exception: A commercial building that must comply with the solar ready
provisions of Section C410.4.2 or that has a permanently-installed on-
site renewable energy system that provides electricity to the building’s
electrical system.
63. A new SECTION C411 INTEGRATED DESIGN ASSISTANCE is added to read
as follows:
SECTION C411 INTEGRATED DESIGN ASSISTANCE
C411.1 Scope. This section establishes criteria for compliance using Appendix G
of ASHRAE 90.1, entitled Performance Rating Method, in accordance with the City
of Fort Collins Integrated Design Assistance Program referred to herein as “IDAP”.
C411.2 Requirements for Integrated Design Assistance. Participation in this
compliance path requires:
1. The project must be an active participant in IDAP.
2. The project must have qualified for the Design Incentive.
C411.3 Documentation. The documentation required for compliance is the
energy report based on the submitted CD drawing package and approved by the
IDAP program manager.
C411.3.1 Compliance report. Permit submittals shall include the energy report
documenting that the proposed design has annual energy costs less than or
equal to the annual energy costs of the baseline building adjusted to current
code and in accordance with IDAP. The report shall include the following
information:
1. Address of the building.
2. An inspection checklist documenting the building component
characteristics of the proposed design. The inspection checklist shall
show the estimated annual energy cost for both the baseline building
adjusted to current code and the proposed design.
3. Name of individual completing the compliance report.
- 37 -
4. Name and version of the compliance software tool.
C411.3.2 Additional documentation. The code official may also require
production of documentation of the building component characteristics of the
Baseline Building including the code Building Performance Factor and
proposed Building Performance Factor.
64. Section C501.2 Compliance is amended to read as follows:
C501.2 Compliance. Additions, alterations, repairs, and changes of occupancy to,
or relocation of, existing buildings and structures shall comply with Sections C502,
C503, C504 and C505 of this code, as applicable, and with the provisions for
alterations, repairs, additions and changes of occupancy or relocation,
respectively, in the International Building Code, International Existing Building
Code, International Fire Code, International Fuel Gas Code, International
Mechanical Code, International Plumbing Code, International Property
Maintenance Code and NFPA 70, as adopted by the City. Changes where
unconditioned space is changed to conditioned space shall comply with Section
C502.
Exceptions:
1. Additions, alterations, repairs or changes of occupancy complying with
ANSI/ASHRAE/IES 90.1.
2. Additions, alterations, repairs or changes of occupancy do not need to
comply with the requirements of C402.2.4 Slabs-on-grade floors when it
would require the demolition of existing permanent building construction
components.
65. Section C502.3.7 Additional energy efficiency credit requirements is
amended to read:
C502.3.7 Additional energy efficiency credit requirements. Additions shall
comply with sufficient measures from Sections C406.2 and C406.3 to achieve
not less than 50 percent of the number of required efficiency credits from Table
C406.1.1(1) based on building occupancy group and climate zone. Where a
project contains multiple occupancies, credits from Table C406.1.1(1) for each
building occupancy shall be weighted by the gross floor area to determine t he
project weighted average energy credits required. Accessory occupancies shall
be included with the primary occupancy group for purposes of this section.
Alterations to the existing building that are not part of the addition, but are
permitted with an addition, shall be permitted to be used to achieve the required
credits. All additions shall also comply with Section C406.1.1.3.
Exceptions:
. . .
66. Section C502.3.8 Renewable energy systems is deleted in its entirety.
- 38 -
67. A new APPENDIX CZ COMMERCIAL PERFORMANCE PATH TO ZERO
CARBON BUILDING is added to read as follows:
APPENDIX CZ
COMMERCIAL PERFORMANCE PATH TO ZERO CARBON BUILDING
SECTION CZ101
GENERAL
CZ101.1 Purpose. This appendix provides requirements that lead to achievement of
zero emissions buildings and identifies future targets that achieve zero emissions
buildings by the 2030 code cycle.
CZ101.2 Scope. New buildings shall comply with the requirements in this appendix.
SECTION CZ102
GENERAL DEFINITIONS
CARBON DIOXIDE EQUIVALENT (CO2e). A measure used to compare the impact
of various greenhouse gases based on their global warming potential (GWP). CO2e
approximates the time-integrated warming effect of a unit mass of a given greenhouse
gas relative to that of carbon dioxide (CO2). GWP is an index for estimating the relative
global warming contribution of atmospheric emissions of a particular greenhouse gas
compared to emissions of an equal mass of CO2.
COMMUNITY RENEWABLE ENERGY FACILITY. A facility that generates electricity
with photovoltaic, solar thermal, geothermal energy, or wind energy systems, and is
qualified as a community energy facility under applicable state and local utility statutes
and rules.
DIRECT OWNERSHIP. An off-site renewable energy system under the ownership or
control of the building project owner.
GREEN RETAIL PRICING. A program by the retail electricity provider to provide 100
percent renewable energy to the building project owner.
GROSS SITE EUI. The energy use intensity (EUI) as measured by the total amount
of energy consumed on the site, in total, with no contributions or deductions from
onsite energy generation or offsite energy generation procurements. Gross Site EUI
shall be measured by total energy consumed and not take into consideration any net
value of energy consumption or deductions made from the gross energy consumption
by renewable onsite energy generation or offsite energy procurement.
NET ONSITE ELECTRICITY CONSUMPTION. The electricity consumption of the site
as measured when contributions from eligible onsite or off -site renewable energy
- 39 -
systems are taken into consideration and subtracted from the gross onsite electricity
consumption. The net onsite electricity consumpti on shall be measured as the total
amount of eligible renewable energy attributable to the building site subtracted from
the gross total amount of onsite electricity consumed by the building site.
RENEWABLE ENERGY INVESTMENT FUND (REIF). A fund established by a
jurisdiction to accept payment from building project owners to construct or acquire
interest in qualifying renewable energy systems, together with their associated RECs,
on the building project owner’s behalf.
RENEWABLE ENERGY POWER PURCHASE AGREEMENT (PPA), FINANCIAL. A
financial arrangement between a renewable electricity generator and a purchaser
wherein the purchaser pays or guarantees a price to the generator for the project’s
renewable generation. Also known as a “financial power purchase agree ment” and
“virtual power purchase agreement.”
RENEWABLE ENERGY POWER PURCHASE AGREEMENT (PPA), PHYSICAL. A
contract for the purchase of renewable electricity from a specific renewable electricity
generator to a purchaser of renewable electricity.
SECTION CZ103
COMPLIANCE
CZ103.1 Compliance. Compliance with this appendix shall be demonstrated using
the Simulated Building Performance option of Section C401.2.1 and by following
Sections CZ103.2 through CZ103.5.
CZ103.2 Building energy compliance. The proposed building model performance
(Gross Site EUI) shall not exceed the applicable code year values in Table CZ103.2(1)
using the energy modeling procedures described in Section C407.4 and Section
CZ103.3; however, the proposed building shall be modeled with no on-site renewable
energy generation. Buildings with multiple occupancy types listed in Table CZ103.2(1)
may develop a performance target based on an area weighted average EUI calculated
by floor area of each occupancy type.
TABLE CZ103.2(1) GROSS SITE EUI TARGETS BY CODE YEARa
Building Type 2024 Performance
Target (kBtu/ft2/year)
2027 Performance
Targetb (kBtu/ft2/year)
2030 Performance
Targetb (kBtu/ft2/year)
Apartment (Type R2) 29 26 24
Primary School 39 24 19
Small Office (<5,000 sf) 20 19 17
Medium Office (5,000-
50,000 sf)
23 21 20
Large office (>50,000 sf) 38 31 23
Secondary School 26 22 19
Warehouse 11 10 9
- 40 -
Retail Store 36 35 34
Small Hotel (<75,000 sf) 41 33 25
Large Hotel (>75,000 sf) 61 54 48
Hospital 74 69 65
Restaurant 228 177 126
Strip Mall 35 30 25
a. Building types not found within this table shall comply with C407 Simulated Building Performance and
CZ103.2.2 Building Emission Compliance.
b. These are projected EUI targets for buildings constructed under the 2027 and 2030 code cycles and are not
required for the 2024 code.
CZ103.2.1 Building emission compliance. The annual energy emissions (AEEp) of
the proposed design shall be less than or equal to the annual energy emissions (AEEb)
of the standard reference design as modified in Equation CZ-1. Electricity energy
emissions for the standard reference design [Equation CZ-2] and proposed design
[Equation CZ-3] shall be calculated using the long-run marginal emission rates from
Table CZ103.4 for each time period. The calculation shall be made using month-hour
(288 values) or annual-hour values (24 values). For fossil fuels and thermal energy,
the CO2e emissions shall be calculated by multiplying the CO2e emission factors
taken from Table CZ103.3.2 by the annual consumption. Compliance using Equation
CZ-1 shall be demonstrated using the emissions factor CO2F found in Table
CZ103.2.1.
TABLE CZ103.2.1 EMISSION FACTORS
Emission Factor (CO2F)
2024 2027a 2030a
0.95 0.50 0.0
a. These are projected CO2F targets for buildings constructed under
the 2027 and 2030 code cycles and are not required for the 2024
code.
Equation CZ-1 AEEp ≤ AEEb * CO2F
where:
AEEx = Annual Energy Emissions of the proposed design (AEEp) or
standard reference design (AEEb).
CO2F = Emission Factor, found in Table CZ103.2.1
Equation CZ-2 AEEb = Σ[qBe,t x ee,t] + Σ [Qi x ei]
Equation CZ-3 AEEp = Σ[qPe,t x ee,t] + Σ [Qi x ei] - AE
where:
- 41 -
qBe,t = Standard reference design electricity consumption for time period t,
MWh
qPe,t = Proposed design net onsite electricity consumption for time period t,
MWh
ee,t = Long-run marginal CO2e emissions rate for electricity in time period t,
found in Table CZ103.4
Qi = Annual energy consumption for fossil fuels or thermal energy, MWh
ei = CO2e emissions rate found in Table CZ103.3.2 for fossil fuel or thermal
energy type i
AE = Avoided CO2e emissions resulting from the purchase of off -site
renewable energy, calculated using Equation CZ-4
CZ103.2.2 Avoided emissions. The avoided emissions from off-site renewable
energy procurement shall be calculated as shown in the following equation and
meet the requirements of Section CZ103.4.
Equation CZ-4 AE = Σ[Qg x REF x AEg] * PF
where:
Qg = annual renewable electricity procured for renewable energy generator
type g, MWh
g = index for generator type
AEg = annual avoided CO2e emissions rate for renewable energy generator
type g from Table CZ103.5(2), kg/MWh
REF = Offsite Renewable Energy Factor which shall equal 0.75
PF = Procurement energy Factor from Table CZ103.5(1)
CZ103.3 Calculation procedure. Except as specified by this section, the standard
reference design and proposed design area shall be configured and analyzed using
identical methods and techniques.
CZ103.3.1 Building specifications. The standard reference design and proposed
design shall be configured and analyzed as specified by Table C407.4.1(1) with
the following modifications:
- 42 -
1. The Heating systems fuel type for the standard reference design shall be
electric.
2. The Cooling systems fuel type for the standard reference design shall be
electric.
3. The Service water heating fuel type for the standard reference design shall
be electric.
For the purpose of compliance with this section, the standard reference design and
proposed design shall comply with all footnotes contained in Table C402.1.2.
CZ103.3.2 Emission rates for fossil fuels and thermal energy. The emissions
factors for fossil fuels or thermal energy to be used in the calculations in Section
CZ103.2.1 shall be as specified in Table CZ103.3.2.
TABLE CZ103.3.2 CO2E EMISSION FACTORS FOR FOSSIL FUELS AND
THERMAL ENERGY
Fossil Fuels Delivered to Buildings CO2e Emissions, kg/MWh
Natural Gas 277
Liquified Petroleum Gas or Propane 295
Fuel Oil (Residual) 334
Fuel Oil (Distillate) 324
Coal 382
Gasoline 337
Other Fuels not Specified in this Table 382
CZ103.4 Long range marginal emission rates. The long-run marginal emission
rates (LRMERs) for the Cambium Generation and Emission Assessment Region
RMPAc, to be used for calculations in Section CZ103.2 (ee,t in Equations CZ-2 and
CZ-3), shall be as specified in Table CZ103.4. The LRMERs are based on a 20-year
CO2e time horizon. The Cambium Generation and Emission Assessment Regions are
shown in Figure CZ-103.4. Where comparing or combining CO2e values, a consistent
GWP time-horizon shall be used for all estimates of CO2e.
- 43 -
FIGURE CZ-103.4 CAMBIUM GENERATION AND EMISSION ASSESSMENT
REGIONS (2021 VERSION)
TABLE CZ103.4 RMPAc - HOURLY AND AVOIDED EMISSIONS (kg/MWh)
Ho
u
r
Ja
n
u
a
r
y
Fe
b
r
u
a
r
y
Ma
r
c
h
Ap
r
i
l
Ma
y
Ju
n
e
Ju
l
y
Au
g
u
s
t
Se
p
t
e
m
b
e
r
Oc
t
o
b
e
r
No
v
e
m
b
e
r
De
c
e
m
b
e
r
An
n
u
a
l
- 223 237 171 158 175 188 209 237 243 227 265 258 217
1 227 232 173 162 174 206 223 240 256 238 269 253 222
2 225 231 168 154 179 198 234 247 244 229 276 259 222
3 229 233 174 155 180 199 234 258 253 222 269 261 224
4 227 225 183 155 175 176 222 244 250 234 259 245 217
5 215 206 175 145 159 157 171 214 231 223 254 240 200
6 224 205 152 140 137 144 145 189 214 203 243 240 187
7 213 182 154 129 146 148 139 170 184 185 226 223 176
8 181 162 150 135 150 144 142 160 183 184 207 200 167
9 172 164 143 138 141 139 132 155 174 188 213 189 162
10 166 174 134 133 146 138 131 154 170 181 220 195 161
11 174 190 140 136 139 138 127 152 166 182 208 190 161
12 178 180 137 140 136 139 124 160 165 190 210 188 161
13 182 171 136 141 141 141 125 160 157 193 208 201 162
- 44 -
14 174 172 135 135 133 133 125 152 155 179 216 217 159
15 198 192 141 147 137 138 127 157 170 193 244 232 172
16 214 212 173 154 152 139 148 184 195 211 233 245 187
17 215 204 193 169 172 150 174 209 215 204 235 238 198
18 209 206 192 175 175 172 181 214 216 204 235 242 202
19 219 204 181 169 173 187 197 218 203 212 230 256 205
20 223 210 180 167 169 184 182 206 210 218 233 244 202
21 223 210 174 161 173 200 193 217 225 229 242 249 208
22 233 216 172 161 183 199 194 230 228 211 255 251 212
23 224 225 166 158 174 182 201 225 232 215 263 263 211
CZ103.5 Off-site renewable energy. Buildings that do not have on-site renewable
energy systems sufficiently sized to fully comply with Section CZ103.2.2 shall procure
off-site renewable energy in accordance with Sections CZ103.5.1 through CZ103.5.3.
TABLE CZ103.5(1) PROCUREMENT FACTOR FOR USE
WITH OFF-SITE RENEWABLE ENERGY
Building Type Procurement Factor
Apartment (Type R2) 1
Primary School 1
Small Office (<5,000 sf) 1
Medium Office (5,000-50,000 sf) 1
Large Office (>50,000 sf) 1
Secondary School 1
Warehouse 1
Retail Store 1
Small Hotel (<75,000 sf) 1
Large Hotel (>75,000 sf) 1
Hospital 3.5
Restaurant 10
Strip Mall 1
All Othera 10
a. Includes the following building types: Laundromat, Food Processing
Establishments, Emergency Systems, Crematory, or other buildings with
high process loads as determined by the code official on a case-by-case
basis.
TABLE CZ103.5(2) AVOIDED EMISSIONS FROM OFF-SITE
PURCHASE OF RENEWABLE ENERGY (kg/MWh)
GEA Region Solar Wind Hydro Geothermal
RMPAc 159 195 187 191
- 45 -
CZ103.5.1 Off-site procurement. The building owner shall be credited for the
total amount of off-site renewable energy required by Equation CZ-1. Procured
off-site energy shall comply with the requirements applicable to at least one of
the following:
1. Community renewable energy facility.
2. Financial renewable energy power purchase agreement.
3. Direct Ownership.
4. Renewable Energy Investment Fund.
5. Green Retail Pricing.
6. The energy source shall produce electricity from solar, wind, or
geothermal energy.
Exceptions:
1. Hydropower from new generation capacity on a non-impoundment or
new generation capacity on an existing impoundment that meets one of
the following conditions:
1.1. The hydropower facility complies with the Low Impact
Hydropower Certification Handbook and is certified by a
nationally recognized accreditation organization.
1.2. The hydropower facility complies with UL 2854 and is certified by
an organization that has the standard in its ISO/IEC 17065 scope
of accreditation.
1.3. The hydropower facility consists of a turbine in a pipeline or a
turbine in an irrigation canal.
For facilities falling under Exception 1.1 or 1.2, only output generated during
the period of certification is eligible for RECs sale in accordance with the
provisions of this section. Renewables from new impoundments of water are
not eligible.
CZ103.5.1.1 Location of energy generation. The generation source shall be
located where the energy can be delivered to the building site by any of the
following:
1. Direct connection to the off-site renewable energy facility.
2. The local utility or distribution entity.
3. An interconnected electrical network where energy delivery capacity
between the generator and the building site is available (Informative
Note: Examples of interconnected electrical networks include regional
- 46 -
power pools and regions served by independent system operators or
regional transmission organizations).
CZ103.5.2 Off-site contract. The renewable energy shall be delivered or credited
to the building site under an energy contract duration of not less than 15 years.
The contract shall be structured to survive a partial or full transfer of ownership of
the building property. The total required off -site renewable energy shall be
procured in equal installments over the duration of the off -site contract.
CZ103.5.3 Renewable Energy Certificate (REC) documentation. The property
owner or owner’s authorized agent shall demonstrate that where RECs are
associated with on-site and off-site renewable energy production, the following
criteria shall be met:
1. The RECs shall be retained and retired by, or on beha lf of the property
owner or tenant for a period of not less than 15 years.
2. The RECs shall be created within a 12-month period of the use of the REC.
3. The RECs represent a generating asset constructed not more than 5 years
before the issuance of the certificate of occupancy.
68. Section R105.2 Information on construction documents is amended to read
as follows:
. . .
10. Window unit area square footage as a percentage of individual wall area
by specific elevation.
11. Locations for condensate drainage where combustion equipment for
space heating and water heating is installed.
69. A new Section R105.6 Permits is added to read as follows:
R105.6 Permits. Procedures related to permits, required inspections, payment of
fees and obtaining required approvals shall be as set forth in Chapter 1 of the
adopted International Building Code.
70. SECTION R106 FEES is deleted in its entirety and replaced with the following:
SECTION R106 FEES
R106.1 Fees. All items relating to fees shall be as specified in Section 109 of the
adopted International Building Code, entitled “FEES.”
71. SECTION R109 MEANS OF APPEALS is deleted in its entirety and replaced with
the following:
- 47 -
SECTION R109 MEANS OF APPEALS
R109.1 General. Appeals of decisions, determinations and interpretations of this
code shall be made pursuant to the applicable provisions of Section 113 of the
adopted International Building Code, entitled “MEANS OF APPEALS.”
72. A new SECTION R111 VIOLATIONS is added to read as follows:
SECTION R111 VIOLATIONS
R111.1 General. Any person who violates a provision of this code or fails to comply
with any of the requirements thereof or who alters or repairs a building or structure
in violation of the approved construction documents or directive of the code official,
or of a permit or certificate issued under the provisions of this code, commits a civil
infraction and is subject to the provisions contained in § 1-15(f) of the City Code.
Each day that a violation continues shall be deemed a separate offense .
73. SECTION R202 GENERAL DEFINITIONS is amended to modify, or add, in
alphabetical order, the following definitions:
. . .
ARCHITECTURAL SHADING. Architectural shading includes roof eaves, exterior
overhangs, fins, latticework, vertical trellises, horizontal pergolas, porches, and
decks that block direct solar radiation in the summer.
. . .
COMBUSTION EQUIPMENT. Any equipment or appliance used for space
heating, service water heating, cooking, clothes drying, or lighting that uses fuel
gas or fuel oil.
. . .
74. Section R401.2 Application is amended to read as follows:
R401.2 Application. Residential buildings shall comply with Section R401.2.1,
R401.2.2, R401.2.3 or R401.2.4, and new buildings shall comply with Appendix
RZ.
Exception: Additions, alterations, repairs and changes of occupancy to
existing buildings complying with Chapter 5.
75. Section R401.2.1 Prescriptive compliance option is amended to read as
follows:
- 48 -
R401.2.1 Prescriptive compliance option. The Prescriptive Compliance Option
requires compliance with Sections R401 through R404 , R408 and R409 and the
requirements of the sections indicated within Table R405.2(1).
76. TABLE R402.1.2 MAXIMUM ASSEMBLY U-FACTORSa AND FENESTRATION
REQUIREMENTS is deleted in its entirety and replaced with the following:
TABLE R402.1.2 MAXIMUM ASSEMBLY U-FACTORSa AND FENESTRATION REQUIREMENTS
CLIMATE
ZONE FENESTRATION
U-FACTOR
SKYLIGHT
U-FACTOR
GLAZED
VERTICAL
FENESTRATION
SHGCd
CEILING
U-FACTOR
INSULATION
ENTIRELY
ABOVE
ROOF DECK
WOOD
FRAME
WALL
U-FACTORe
MASS WALL
U-
FACTORb
FLOOR
U-
FACTOR
BASEMENT
WALL
U-
FACTOR
CRAWL
SPACE
WALL
U-
FACTOR
5 0.28/0.25f 0.50 0.35/43g 0.026 0.032 0.045 0.082 0.028 0.050 0.050
For SI: 1 foot = 304.8mm
a. Nonfenestration U-factors shall be obtained from measurement, calculation or an approved source.
b. Mass walls shall be in accordance with Section R402.2.5. Where more than half the insulation is on the interior, the mass
wall U-factors shall not exceed 0.065.
c. In Warm Humid locations as defined by Figure R301.1 and Table R301.1, the basement wall U-factor shall not exceed
0.360.
d. The SHGC column applies to all glazed fenestration.
e. Class 1 vapor retarders shall not be installed on the interior of framed walls where exterior ci value is less than R-7.5.
f. Where the sum area of all window units within an elevation is greater than 30% of the total wall area elevation, as provided
per Section R105.2 Information on construction documents, the second U-factor shall be required.
g. Where the SHGC exceeds 0.35 on wall elevations that orient west or southwest, horizontal or vertical architectural shading
optimized for solar noon on the summer solstice shall be installed to block solar radiation.
77. TABLE R402.1.3 INSULATION MINIMUM R-VALUES AND FENESTRATION
REQUIREMENTS BY COMPONENTa is deleted in its entirety and replaced with
the following:
TABLE R402.1.3 INSULATION MINIMUM R-VALUES AND FENESTRATION
REQUIREMENTS BY COMPONENTa
CLIMATE
ZONE
FENESTRATION
U-FACTORb
SKYLIGHT
U-FACTORb
GLAZED
VERTICAL
FENESTRATION
SHGCb
CEILING
R-
VALUE
INSULATION
ENTIRELY
ABOVE
ROOF DECK
WOOD
FRAME
WALL
R-VALUEg
MASS
WALL
R-VALUEf
FLOOR
R-
VALUE
BASEMENTc,e
WALL
R-VALUE
SLABd R-
VALUE &
DEPTH
CRAWL
SPACEc,e
WALL R-
VALUE
5 0.28/0.25h 0.50 0.35/0.43i 49 30ci
30 or
20&5ci
or
13&10c
i or
0&20ci
13/17 38
19ci or 19
or 13&5ci
or exterior
10ci
10ci, 3 ft
19ci or
19 or
13&5ci
- 49 -
For SI: 1 foot = 304.8 mm
ci = continuous insulation
a. R-values are minimums. U-factors and SHGC are maximums. Where insulation is installed in a cavity that is less
than the label or design thickness of the insulation, the installed R-value of the insulation shall be not less than the
R-value specified in the table.
b. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration.
c. “5ci or 13” means R-5 continuous insulation (ci) on the interior or exterior surface of the wall or R-13 cavity insulation
on the interior side of the wall. “10ci or 13” means R-10 continuous insulation (ci) on the interior or exterior surface of
the wall or R-13 cavity insulation on the interior side of the wall. “15ci or 19 or 13 + 5ci” means R -15 continuous
insulation (ci) on the interior or exterior surface of the wall; or R-19 cavity insulation on the interior side of the wall; or
R-13 cavity insulation on the interior of the wall in addition to R-5 continuous insulation on the interior or exterior
surface of the wall.
d. R-5 insulation shall be provided under the full slab area of a heated slab in addition to the required slab edge insulation
R-value for slabs. The install of continuous insulation shall be required for all heated slabs. The slab-edge insulation
for heated slabs shall not be required to extend below the slab. Insulation located below grade shall be extended the
distance provided in the table or to top of footing.
e. The first value is cavity insulation; the second value is continuous insulation. Therefore, as an example, “13 + 5”
means R-13 cavity insulation plus R-5 continuous insulation.
f. Mass walls shall be in accordance with Section R402.2.5. The second R-value applies where more than half of the
insulation is on the interior of the mass wall where more than half the insulation is on the interior, the mass wall U-
factor shall be the same as the frame wall U- factor.
g. Class 1 vapor retarders shall not be installed on the interior of framed walls where exterior ci value is less than R-
7.5.
h. Where the sum area of all window units within an elevation is greater than 30% of the total wall area elevation, as
provided per Section R105.2 Information on construction documents, the second U-factor shall be required.
i. Where the SHGC exceeds 0.35 on wall elevations that orient west or southwest, horizontal or vertical architectural
shading optimized for solar noon on the summer solstice shall be installed to block solar radiation.
78. Section R402.2 Specific insulation requirements is amended to read as follows:
R402.2 Specific insulation requirements. In addition to the requirements of
Section R402.1, insulation shall meet the specific requirements of Sections
R402.2.1 through R402.2.13. All insulation shall be installed to meet the
requirements of a Grade 1 insulation installation in accordance with Appendix A of
ANSI/RESNET/ICC 301.
79. Section R402.2.5 Access hatches and doors is amended to read as follows:
R402.2.5 Access hatches and doors. Access hatches and doors from
conditioned to unconditioned spaces such as attics and crawl spaces shall be
insulated to the same R-value required by Table R402.1.3 for the wall or ceiling
in which they are installed.
Exceptions:
1. Vertical entries providing access from conditioned spaces to
unconditioned spaces that are not required to be a swinging door
shall be less than or equal to U-0.10 or have an average insulation
R-value of R-10 or greater. If foam plastic insulation is used, it shall
comply with Section R303.5.3 of the International Residential Code,
entitled Attics.
. . .
- 50 -
80. Section R402.2.9.1 Basement wall insulation installation is amended to read
as follows:
R402.2.9.1 Basement wall insulation installation. Where basement walls
are insulated, the insulation shall be installed from the top of the basement
wall down to the basement floor, or in accordance with the proposed design
or the rated design, as applicable.
81. Section R402.2.10.1 Slab-on-grade floor insulation installation is amended to
read as follows:
R402.2.10.1 Slab-on-grade floor insulation installation. For buildings
complying with Section R401.2.1, R401.2.2, and R401.2.3, the slab edge
continuous insulation shall extend downward from the top of the slab on the
outside or inside of the foundation wall. Insulation located below grade shall
extend the distance provided in Table R402.1.3, but need not exceed the
footing depth in accordance with Section R403.1.4 of the International
Residential Code. Where a proposed design includes insulation extending
away from the building, it shall be protected by pavement or by not less than
10 inches (254 mm) of soil. The top edge of the insulation installed between
the exterior wall and the edge of the interior slab shall be permitted to be cut at
a 45-degree (0.79 rad) angle away from the exterior wall. Where horizontal
sections of insulation not greater than 8 inches (203.2 mm) require
compressive strength, a structural thermal material with an R-value not less
than R-1.8 shall suffice to maintain an installation without thermal breaks. Full-
slab insulation shall be continuous under the entire area of the slab -on-grade
floor, except at structural column locations and service penetrations. Slab edge
insulation required at the heated slab perimeter shall not be required to extend
below the bottom of the heated slab and shall be continuous with the full slab
insulation.
82. Section R402.2.11.1 Crawl space wall insulation installations is deleted in its
entirety and replaced with the following:
R402.2.11.1 Crawl space wall insulation installations. Where crawl
space wall insulation is installed, it shall be permanently fastened to the
interior or exterior wall and shall extend downward from the top of
foundation wall to the footing. Exposed earth in unvented crawl space
foundations shall be covered with a continuous Class I vapor retarder in
accordance with the adopted International Building Code or the
International Residential Code, as applicable. Joints of the vapor retarder
shall overlap by 12 inches (304.8 mm) and be sealed or taped. The edges
of the vapor retarder shall extend 12 inches (304.8 mm) up stem walls and
6 inches (153 mm) up footings and shall be attached and sealed to the stem
walls and footing pads.
- 51 -
83. TABLE R402.5.1.1 AIR BARRIER, AIR SEALING AND INSULATION
INSTALLATIONa is amended to read as follows:
TABLE R402.5.1.1 AIR BARRIER, AIR SEALING AND INSULATION
INSTALLATIONa
COMPONENT AIR BARRIER CRITERIA INSULATION INSTALLATION
CRITERIA
General
requirements
The building’s thermal envelope shall
contain a continuous air barrier that is in
alignment with the insulation on the
conditioned and unconditioned side of
the assembly.b
All penetrations, breaks or joints in the
air barrier shall be air sealed.
Air-permeable insulation shall be enclosed
inside the air barrier assembly.ᵇ
. . . . . . . . .
Walls
The junction of the foundation and the
sill plate shall be sealed. The junction of
the top plate and the top of exterior
walls and interior walls that are adjacent
to or abut unconditioned space shall be
sealed. Knee walls shall have an air
barrier installed on both sides of the
insulation and be sealed on all edges.
Cavities within corners and headers of frame
walls shall be insulated by completely filling the
cavity with a material having a thermal
resistance, R-value, of not less than R-3 per
inch. Exterior building thermal envelope
insulation for framed walls shall be installed in
substantial contact and continuous alignment
with the air barrier.
Knee wall
Knee walls shall have an air barrier
installed on both sides of the insulation
and be sealed on all edges.
Insulation installed in a knee wall assembly shall
be installed in accordance with Section
R402.2.3.
Air-permeable insulation shall be enclosed inside
an air barrier assembly.
. . . . . . . . .
Rim joists
Rim joists shall include an exterior air
barrier.b
The junctions of the rim board to the sill
plate and the rim board and the subfloor
shall be air sealed.
Rim joists shall be insulated so that the
insulation maintains permanent contact with the
exterior rim boardb
. . . . . . . . .
a. Inspection of log walls shall be in accordance with the provisions for ICC 400.
b. Air barrier and insulation full enclosure is not required in unconditioned/ventilated attic spaces and rim joists.
84. Section R402.5.1.2 Air leakage testing is amended to read as follows, with
Exception 1 being deleted in its entirety:
R402.5.1.2 Air leakage testing. The building or each dwelling unit or sleeping unit
in the building shall be tested for air leakage. Testing shall be conducted in
accordance with ANSI/RESNET/ICC 380, ASTM E779, ASTM E1827 or ASTM
E3158. Testing shall also be conducted in accordance with the City of Fort Collins
Building Code Residential Air Tightness Testing Protocol, New Attached and
Detached Single Family Dwellings, dated December 16, 2025 (Ordinance No. 212,
2025), and reported at a pressure differential of 0.2-inch water gauge (50 Pa).
Where required by the code official, testing shall be conducted by an approved
third party. A written report of the results of the test shall identify the technician
conducting the test and their applicable testing certifications, and shall be signed
- 52 -
by the technician conducting the test and provided to the code official. Testing shall
be performed at any time after creation of all penetrations of the building thermal
envelope have been sealed.
During testing:
. . .
6. Supply and return registers, where installed at the time of the test, shall be
fully open.
7. The connection to an attached garage(s) must be verified either as not
exceeding 5 Pa, as tested pressure not lower than -45 Pa with respect to
(WRT) house at a pressure differential of 0.2 inch water gauge (50 Pa), or
as not exceeding 100 CFM with respect to (WRT) house through the Open
a Door test as documented in the City of Fort Collins Building Code Air
Tightness Testing Protocol, New Attached and Detached Single Family
Dwellings.
Exception: Where tested in accordance with Section R402.5.1.2.1,
testing of each dwelling unit or sleeping unit is not required.
85. Section R402.5.1.2.1 Unit sampling is amended to read as follows:
R402.5.1.2.1 Unit sampling. For buildings with eight or more dwelling units or
sleeping units, a minimum of seven or 20 percent of the dwelling units or
sleeping units, whichever is greater, shall be tested including one of each unit
type and a like number of units on each floor. Where the air leakage rate of a
tested unit is greater than the maximum permitted rate, corrective actions shall
be taken and the unit retested until it passes. For each tested dwelling unit or
sleeping unit with an air leakage rate greater than the maximum permitted rate,
three additional units, including the corrected unit, shall be tested. Where
buildings have fewer than eight dwelling units or sleeping units, each unit shall
be tested.
86. Section R402.5.1.3 Maximum air leakage rate is amended to read as follows:
Section R402.5.1.3 Maximum air leakage rate. Where tested in
accordance with Section R402.5.1.2, the air leakage rate for buildings,
dwelling units or sleeping units shall be as follows:
1. Where complying with Section R401.2.1, R401.2.2 or R401.2.3,
the building or the dwelling units or sleeping units in the building
shall have an air leakage rate not greater than 3.0 air changes
per hour or 0.16 CFM per square foot of testing unit enclosure
area.
Exception: Where dwelling units or sleeping units are attached or
located in an R-2 occupancy, and are tested without simultaneously
- 53 -
testing adjacent dwelling units or sleeping units, the air leakage rate
is permitted to be not greater than 0.27 cubic feet per minute per
square foot [1.4 L/(s × m2)] of the testing unit enclosure area. Where
adjacent dwelling units are simultaneously tested in accordance with
ASTM E779, the air leakage rate is permitted to be not greater than
0.27 cubic feet per minute per square foot [1.4 L/(s × m 2)] of the
testing unit enclosure area that separates conditioned space from
the exterior.
87. Section R402.6 Maximum fenestration U-factor and SHGC is amended to read
as follows:
R402.6 Maximum fenestration U-factor and SHGC. The area-weighted average
maximum fenestration U-factor permitted using tradeoffs from Section R402.1.5 or
R405 or R406 shall be 0.32 for vertical fenestration, and 0.75 for skylights. The
area-weighted average maximum fenestration SHGC permitted using tradeoffs
from Section R405 or R406 shall be 0.35. Fenestration with an SHGC not greater
than 0.43 shall be permitted, but where installed on wall elevations that orient west
or southwest, horizontal or vertical architectural shading optimized for solar noon
on the summer solstice shall be installed to block solar radiation.
Exception: The maximum U-factor and SHGC for fenestration shall not be
required in storm shelters complying with ICC 500.
88. Section R403.1.2 Heat pump supplementary heat is amended to read as
follows:
R403.1.2 Heat pump supplementary heat. Heat pumps having
supplementary electric-resistance, fuel gas or liquid fuel heating systems shall
have controls that are configured to prevent supplemental heat operation when
the capacity of the heat pump compressor can meet the heating load and when
outdoor temperature exceeds 15°F (-9.4°C). Supplemental heat operation shall
be limited to only where one of the following applies:
1. The vapor compression cycle cannot provide the necessary heating
energy to satisfy the thermostat setting.
2. The heat pump is operating in defrost mode.
3. The vapor compression cycle malfunctions.
4. The thermostat malfunctions.
75. Section R403.3.4 Duct systems located in conditioned space is deleted in its
entirety and replaced with the following:
R403.3.4 Ducts located in conditioned space. For ductwork to be considered
inside conditioned space, the space conditioning equipment and duct system shall
be located completely within the building thermal envelope and air barrier
boundary.
- 54 -
76. Section R403.3.8 Duct system leakage is amended to read as follows:
R403.3.8 Duct system leakage. The total measured duct system leakage shall
not be greater than 4.0 cubic feet per minute (113.2 L/min) per 100 square feet
of the conditioned floor area. For buildings complying with Section R405 or
R406, where duct system leakage to outside is tested in accordance with
ANSI/RESNET/ICC 380 or ASTM E1554, the leakage to outside value shall not
be used for compliance with this section, but shall be permitted to be used in
the calculation procedures of Section R405 and R406. Where space
conditioning equipment is not installed at time of testing, the supply and return
duct system leakage shall not be greater than 3.0 cubic feet per minute (84.9
L/min) per 100 square feet (9.3 m2) of the conditioned floor area.
77. Section R403.3.9 Unit sampling is amended to read as follows:
R403.3.9 Unit sampling. For buildings with eight or more dwelling units or
sleeping units, the duct systems in the greater of seven or 20 percent of the
dwelling units or sleeping units, including one of each unit type and a like
number of units on each floor, shall be tested. Where buildings have fewer than
eight dwelling units or sleeping units, the duct systems in each unit shall be
tested. Where the leakage of a duct system is greater than the maximum
permitted duct system leakage, corrective actions shall be made to the duct
system and the duct system shall be system retested until it passes. For each
tested dwelling unit or sleeping unit that has a greater total duct system leakage
than the maximum permitted duct system leakage, an additional three dwelling
units or sleeping units, including the corrected unit, shall be tested.
78. Section R403.4.1 Protection of piping insulation is amended to read as
follows:
R403.4.1 Protection of piping insulation. Piping insulation exposed to
weather shall be protected from damage, including that caused by sunlight,
moisture, physical contact and wind. The protection shall provide shielding from
solar radiation that can cause degradation of the material and shall be
removable not less than 6 feet (1828 mm) from the equipment for maintenance.
Adhesive tape, paint products and similar applications that require
maintenance shall be prohibited.
79. A new Section R403.5.4 Demand responsive water heating and TABLE
R403.5.4 DEMAND RESPONSIVE CONTROLS FOR WATER HEATING are
added to read as follows:
R403.5.4 Demand responsive water heating. Storage water heaters that use
electricity for water heating with a rated water storage volume of 40 gallons
(150 L) to 120 gallons (450 L) and a nameplate input rating equal to or less
than 12 kW shall be provided with demand responsive controls in accordance
with Table R403.5.4.
- 55 -
Exceptions:
1. Water heaters that are required to provide a constant hot water
delivery temperature of 180°F (82°C) or greater.
2. Water heaters that comply with Section IV, Part HLW or Section X of
the ASME Boiler and Pressure Vessel Code.
3. Water heaters that use three-phase electric power.
TABLE R403.5.4 DEMAND RESPONSIVE CONTROLS FOR WATER
HEATING
Equipment Type
Controls
Manufactured before 7/1/2025 Manufactured on or
after 7/1/2025
Electric storage water
heaters
AHRI 1430 (I-P) or ANSI/CTA-2045-B
Level 1 and also capable of initiating
water heating to meet the temperature
set point in response to a demand
response signal.
AHRI 1430 (I-P)
80. Section R403.6.3 Testing is amended by deleting Exception 3.
81. Section R403.6.4 Unit sampling is deleted in its entirety.
82. Section R403.7 Equipment sizing and efficiency rating is amended to read as
follows:
R403.7 Equipment sizing and efficiency rating. Heating and cooling equipment
shall be designed and sized in accordance with Section M1401.3 of the
International Residential Code, and performance will be performance tested and
verified in accordance with Section M1309 of the International Residential Code.
83. Section R403.7.1 Electric-resistance space heating is amended to read as
follows:
R403.7.1 Electric-resistance space heating. Detached one- and two-family
dwellings, townhouses and dwelling units using electric-resistance space heating
shall limit the total installed heating capacity of all electric-resistance space heating
serving the dwelling unit to not more than 2.0 kW or shall install a heat pump in
accordance with Section R403.7.2 in the largest space that is not used as a
bedroom.
84. A new Section R403.7.2 Space heating for electrification is added to read as
follows:
- 56 -
R403.7.2 Space heating for electrification. Space heating equipment shall be
constructed with or pre-wired to support a ground-source electric heat pump or an
electric cold climate heat pump that is specifically designed to heat at the Winter
Outdoor, Design Dry-Bulb temperature defined in Section C302.1. Supplementary
heat shall meet the requirements of Section R403.1.2.
85. Section R404.4 Renewable energy certificate (REC) documentation is
deleted in its entirety.
86. Section R405.1 Scope is amended to read as follows:
R405.1 Scope. This section establishes criteria for compliance using simulated
building performance analysis. Such analysis shall include heating, cooling,
mechanical ventilation and service water-heating energy only.
87. A new Section R405.1.1 Space heating for electrification is added to read as
follows:
R405.1.1 Space heating for electrification. In addition to all required
sections, new buildings, additions, or alterations where the primary heat source
is electrical shall comply with Section R403.7.2.
88. Section R405.2 Simulated building performance compliance and TABLE
R405.2 REQUIREMENTS FOR SIMULATED BUILDING PERFORMANCE are
amended to read as follows:
R405.2 Simulated building performance compliance. Compliance based on
simulated building performance requires that a building comply with the following:
1. The requirements of the sections indicated within Table R405.2(1).
. . .
TABLE R405.2(1) REQUIREMENTS FOR SIMULATED BUILDING
PERFORMANCE AND PRESCRIPTIVE COMPLIANCE
SECTIONa TITLE
. . . . . .
Mechanical
. . . . . .
TABLE R405.2(2) Compactness of the hot water distribution system
. . . . . .
. . .
- 57 -
89. A new TABLE 405.2(2) COMPACTNESS OF THE HOT WATER DISTRIBUTION
SYSTEM is added to read as follows:
TABLE R405.2(2) COMPACTNESS OF THE HOT WATER DISTRIBUTION
SYSTEM
HWDS = factor for the compactness of the hot water distribution system.
Compactness ratioa factorb HWDS
1 story 2 or more stories
≤ 60% or ≤ 70% stacked Multi-Family units ≤ 30% 0.05
a. The factor for the compactness of the hot water distribution system is the ratio of the area of the rectangle that
bounds the source of hot water and the fixtures that it serves (the “hot water rectangle”) divided by the floor area of
the dwelling, defined as any occupiable living space where plumbing fixtures may exist.
1. Sources of hot water include water heaters, or in multifamily buildings with central water heating systems,
circulation loops or electric heat traced pipes.
2. The hot water rectangle shall include the source of hot water and the points of termination of all hot water fixture
supply piping.
3. The hot water rectangle shall be shown on the floor plans and the areas shall be computed to the nearest square
foot.
4. Where there is more than one water heater, and each water heater serves different plumbing fixtures and
appliances it is permissible to establish a separate hot water rectangle for each hot water distribution system
and add the area of these rectangles together to determine the compactness ratio.
5. The basement, crawl space, or attic shall be counted as a story when it contains the water heater. The attic or
crawl space areas do not contribute to the floor area of the dwelling.
6. Compliance shall be demonstrated by providing a drawing on the plans that shows the hot water distribution
system rectangle(s), comparing the area of the rectangle(s) to the floor area of the dwelling and identifying the
appropriate compactness ratio and HWDS factor.
b. Failure to meet compliance with the Compactness ratio factor shall require a hot water circulation system in the
dwelling unit. This system shall have controls that comply with Section R403.5.1.1.1 or Section C404.6.1.1 and shall
have no more than 16 ounces in the piping from the circulation loop to the plumbing fixtures and appliances. The
volume shall be calculated in accordance with TABLE C404.5.2.1.
90. Section R405.5.4.2 Compliance report for certificate of occupancy is
amended to read as follows:
R405.5.4.2 Compliance report for certificate of occupancy. A
compliance report generated for submission prior to obtaining the certificate
of occupancy shall include the following:
. . .
8. A passing “Confirmed” energy rating report, including the Home
Energy Rating Certificate with corresponding Home Energy Rating
System (HERS) score, reflecting as-built data, is required to receive
a Certificate of Occupancy for final approval of a completed home.
91. TABLE R406.2 REQUIREMENTS FOR ENERGY RATING INDEX is amended to
read as follows:
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TABLE R406.2 REQUIREMENTS FOR ENERGY RATING INDEX
SECTIONa TITLE
. . . . . .
Building Thermal Envelope
. . . . . .
R402.6 Maximum fenestration U-Factor and SHGC
. . . . . .
Mechanical
. . . . . .
R403.7 Equipment sizing and efficiency rating
. . . . . .
TABLE R405.2(2)
Compactness of the hot water distribution system
. . . . . .
Other
R409 Electric ready and solar ready
a. Reference to a code section includes all of the relative subsections except as indicated in the table.
b. The factor for the compactness of the hot water distribution system is the ratio of the area of the rectangle that
bounds the source of hot water and the fixtures that it serves (the “hot water rectangle”) divided by the floor area of
the dwelling, defined as any occupiable living space where plumbing fixtures may exist.
1. Sources of hot water include water heaters, or in multifamily buildings with central water heating systems, circulation
loops or electric heat traced pipes.
2. The hot water rectangle shall include the source of hot water and the points of termination of all hot water fixture
supply piping.
3. The hot water rectangle shall be shown on the floor plans and the areas shall be computed to the nearest square
foot.
4. Where there is more than one water heater, and each water heater serves different plumbing fixtures and appliances
it is permissible to establish a separate hot water rectangle for each hot water distribution system and add the area
of these rectangles together to determine the compactness ratio.
5. The basement, crawl space, or attic shall be counted as a story when it contains the water heater. The attic or crawl
space areas do not contribute to the floor area of the dwelling.
6. Compliance shall be demonstrated by providing a drawing on the plans that shows the hot water distribution
system rectangle(s), comparing the area of the rectangle(s) to the floor area of the dwelling and identifying the
appropriate compactness ratio and WDS factor.
c. Failure to meet compliance with the Compactness ratio factor shall require a hot water circulation system in the
dwelling unit. This system shall have controls that comply with Section R403.5.1.1.1 or Section C404.6.1.1 and shall
have no more than 16 ounces in the piping from the circulation loop to the plumbing fixtures and appliances. The
volume shall be calculated in accordance with TABLE C404.5.2.1.
92. Section R406.7.2.2 Confirmed compliance report for a certificate of
occupancy is amended to read as follows:
R406.7.2.2 Confirmed compliance report for a certificate of
occupancy. A confirmed compliance report submitted for obtaining the
certificate of occupancy shall be made site and address specific and include
the following:
. . .
7. A passing “Confirmed” energy rating report that includes a registry
ID from the overseeing organization, reflecting as-built data, is
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required to receive a Certificate of Occupancy for final approval of a
completed home.
93. A new SECTION R409 ELECTRIC READY AND SOLAR READY is added to read
as follows:
SECTION R409 RESIDENTIAL ELECTRIC READY AND SOLAR READY
R409.1 Scope. This section establishes requirements for electric readiness and
solar readiness in residential buildings.
R409.2 Compliance. Residential buildings shall comply with Sections R409.3
through R409.4.
R409.3 Electric ready.
R409.3.1 General. The provisions of Section R409.3 shall apply to all new
buildings, major renovations, and additions.
R409.3.2 Additional electric infrastructure. Combustion equipment in
residential buildings shall meet the requirements of Sections R409.3.2.1
through R409.3.2.5.
Exceptions:
1. Interior fireplaces that do not serve as a primary source of heating.
2. Exterior fireplaces and firepits.
R409.3.2.1 Combustion equipment. Combustion equipment shall be
provided with all of the following:
1. A dedicated, appropriately phased branch circuit sized to
accommodate future electric equipment or appliances to serve a
comparable capacity to meet the heating load.
1.1 The branch circuits serving future electric clothes drying
equipment and cooking equipment shall be sized with a rating
not less than 240 volts and not less than 30 amperes.
2. An electric receptacle or junction box that meets the requirements of
Section R409.3.2.4 and is connected to the electrical panel through
the branch circuit. Each electrical receptacle or junction box shall
have reasonable access to the combustion equipment or dedicated
physical space for future electric equipment with no obstructions
other than the current combustion equipment.
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3. Where combustion equipment is used for space or water heating,
dedicated physical space shall be provided for future electric
equipment, including an electric resistance backup coil for ducted
systems, if applicable. Physical space occupied by existing
combustion equipment shall be permitted to count towards satisfying
the physical space requirement, subject to approval by the code
official.
Exception: Dwelling units with installed air conditioning systems are not
required to provide additional dedicated physical space for an outdoo r
heat pump.
R409.3.2.2 Electrical panel space. The electrical panel shall have a
reserved space for a minimum two-pole circuit breaker for each branch
circuit provided for future electric equipment or appliances. The electrical
panel shall be sized for the electrical load necessary to meet an equivalent
electrical load for any combustion equipment. Electrical loads shall be
calculated in accordance with the National Electrical Code.
R409.3.2.3 Labeling. The junction box or receptacle and the dedicated
circuit breaker space serving future electric equipment or appliances in the
electrical panel shall be labeled for their intended use.
R409.3.2.4 Adjacency. The electrical receptacle or junction box must be
provided within 3 feet of the combustion equipment or appliances, or within
3 feet of the dedicated physical space for future electric equipment or
appliances.
Exception: For combustion equipment dedicated to space or water
heating, the electrical receptacle or junction box shall be located not
more than 6 feet from the combustion equipment or the dedicated
physical space for future electric equipment.
R409.3.2.5 Condensate drain. Where combustion equipment for space
heating and water heating is installed, a location shall be provided for
condensate drainage.
R409.4 Solar ready.
R409.4.1 General. The provisions of Section 409.4 shall apply to new
buildings, and major renovations and additions.
R409.4.2 Solar-ready zone for single family and townhouses. New
detached one- and two-family dwellings and townhouses with at least 600
square feet (55.7 m2) of roof area that is either oriented between 110 degrees
and 270 degrees of true north or a low sloped roof shall comply with Sections
R409.4.2.1 through R409.4.2.8.
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Exceptions:
1. New detached one- and two-family dwellings and townhouses with a
permanently installed on-site renewable energy system that provides
electricity to the dwelling unit’s electrical system.
2. A detached one- or two-family dwelling or townhouse where all areas
of the roof that would otherwise meet the requirements of this section
are in full or partial shade for more than 70 percent of daylight hours
annually.
R409.4.2.1 Construction document requirements for solar-ready zone.
Construction documents shall indicate the solar-ready zone.
R409.4.2.2 Solar-ready zone areas. The total solar-ready zone area for
each detached one- or two-family dwelling or townhouse shall be at least
300 square feet (27.9 m2) exclusive of mandatory access or setback areas
required by the International Fire Code. The solar-ready zone shall be
composed of areas at least 5 feet (1524 mm) in width and at least 80 square
feet (7.43 m2) exclusive of access or setback areas required by the
International Fire Code.
Exception: New townhouses three stories or less in height above grade
plane and with a total floor area less than or equal to 2,000 square feet
(185.8 m2) of conditioned space per townhouse unit shall have a solar-
ready zone area of at least 150 square feet (13.9 m2).
R409.4.2.3 Obstructions. Solar-ready zones shall be free from
obstructions, including but not limited to vents, chimneys, and roof -mounted
equipment.
R409.4.2.4 Shading. The solar-ready zone shall be set back from any
existing or new permanently affixed object on the building or site that is
located south, east, or west of the solar-ready zone a distance not less than
two times the object’s height above the nearest point on the roof surface.
Such objects include, but are not limited to, taller portions of the building
itself, parapets, chimneys, antennas, signage, rooftop equipment, trees,
and roof plantings either existing at the time of permit application or planned
for on the construction documents.
R409.4.2.5 Roof load documentation. The structural design loads of roof
dead load and roof live load shall be clearly indicated on the construction
documents.
R409.4.2.6 Interconnection pathway. Construction documents shall
indicate at least one potential pathway for routing of conduit and/or raceway
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from the solar-ready zone to the electrical service panel and shall be labeled
as “Potential Pathway” on the construction documents.
R409.4.2.7 Electrical service reserved space. The main electrical service
panel shall have sufficient reserved space, which shall be labeled “For
Future Solar Electric,” to allow the installation of a dual pole circuit breaker
for future solar electric installation. The reserved space shall be positioned
at the opposite (load) end from the input feeder location or main circuit
location.
R409.4.2.8 Construction documentation certificate. A permanent
certificate, indicating the solar-ready zone and other requirements of
Sections R409.4.2.1 through R409.4.2.7, shall be posted near the electrical
distribution panel, water heater, or another conspicuous location.
R409.4.3 Solar-ready zone for multifamily. New Group R-2, R-3, and R-4
buildings three stories or less in height above grade plane that have a roof
oriented between 110 and 270 degrees of true north or have low-sloped roofs
shall have a solar-ready zone that complies with Sections R409.4.3.1 through
R409.4.3.6.
Exceptions:
1. A building with a permanently installed, on-site renewable energy
system that meets the following criteria:
1.1 The system produces the energy output equivalent to covering
40 percent of the net roof area with solar photovoltaic
calculated as the horizontally projected gross roof area less
the area covered by skylights, occupied roof decks, vegetative
roof areas, and mandatory access or setback areas required
by the International Fire Code.
1.2 The system is located on the roof or overhang of the building
or on the roof or overhang of another structure located within
250 feet (76200 mm) of the building, on the building site, on
covered parking, or another approved location installed with
the building project and under the same property ownership.
2. A building with a solar-ready zone that is shaded for more than 70
percent of daylight hours annually.
3. A building where a licensed design professional certifies that the
incident solar radiation available to the building is not suitable for a
solar-ready zone.
4. A building where a licensed design professional certifies that the
solar-ready zone area required by Section R409.4.3.2 cannot be met
because of extensive rooftop equipment, skylights, vegetative roof
areas, or other obstructions.
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R409.4.3.1 Construction document requirements for solar-ready zone.
Construction documents shall indicate the solar-ready zone.
R409.4.3.2 Solar-ready zone area. The total solar-ready zone area shall
be at least 40 percent of the roof area calculated as the horizontally
projected gross roof area less the area covered by skylights, occupied roof
decks, vegetative roof areas, and mandatory access or setback areas
required by the International Fire Code. The solar-ready zone shall be a
single area or smaller, separated sub-zone areas. For sloped roofs, each
sub-zone area shall be at least 200 square feet (18.6 m2) and no side of
any rectangular area shall be less than 11 feet (3.35 m) in length. For low-
sloped or flat roofs, each sub-zone area shall be at least 330 square feet
(30.7 m2), with a minimum length running generally north to south of 15 feet
(4.57 m) and a minimum length running generally east to west of 22 feet
(6.7 m), and no side of any rectangular area shall be less than 11 feet (3.35
m) in length. The solar-ready zone shall be located on the roof or overhang
of the building or on the roof or overhang of another structure located within
250 feet of the building, on the building site, on covered parking, or another
approved location installed with the building project and under the same
property ownership.
R409.4.3.3 Obstructions. Solar-ready zones shall be free from
obstructions, including pipes, vents, ducts, HVAC equipment, skylights, and
roof-mounted equipment.
R409.4.3.4 Roof loads and documentation. The structural design loads
for roof dead load and roof live load shall be indicated on the construction
documents.
R409.4.3.5 Interconnection pathway. Construction documents shall
indicate at least one potential pathway for routing of conduit and/or raceway
from the solar-ready zone to an electrical service panel and shall be labeled
as “Potential Pathway” on the construction documents.
R409.4.3.6 Electrical service reserved space. The main electrical service
panel shall have a minimum bus bar rating of not less than 200 amps. The
main electrical service panel shall have a reserved space to allow
installation of a dual pole circuit breaker for future solar electric. This space
shall be labeled “For Future Solar Electric.” The reserved space shall be
positioned at the end of the panel that is opposite from the panel supply
conductor connection.
R409.4.4 Electric service reserved space for solar capacity. The main
electrical service panel shall have sufficient reserved space, which shall be
labeled “For Future Solar Electric,” to allow installation of a dual pole circuit
breaker for future solar electric installation. The reserved space shall be
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positioned at the opposite (load) end from the input feeder location or main
circuit location.
Exception: A residential building that already must comply with the solar
ready provisions of either Section R409.4.2 or R409.4.3 or that has a
permanently-installed on-site renewable energy system that provides
electricity to the building’s electrical system.
94. Section R501.2 Compliance is amended to read as follows:
. . .
Exception: Additions, alterations, repairs or changes of occupancy do not
need to comply with the requirements of Section R402.2.10 Slab-on-grade
floors when it would require the demolition of existing permanent building
construction components.
95. Section R502.2 Prescriptive compliance is amended to read as follows:
R502.2 Prescriptive compliance. Additions shall comply with Sections R502.2.1
through R502.3.
96. Section R502.2.1 Building thermal envelope is amended to read as follows:
R502.2.1 Building thermal envelope. New building thermal envelope
assemblies that are part of the addition shall comply with Sections R402.1,
R402.2, R402.4.1 through R402.4.5, and R402.5.
Exceptions:
1. New building thermal envelope assemblies are exempt from the
requirements of Section R402.5.1.2.
2. Where new construction roof lines for additions are built to match
existing roof lines, a minimum of uncompressed R-16 insulation
extending over the wall top plate at the eaves shall be allowed.
3. Where demolition of existing permanent building construction
components is required to meet the requirements of Section
R402.2.10, Slab-on-grade floors.
97. Section R502.2.2 Heating and cooling systems is amended to read as follows:
R502.2.2 Heating and cooling systems. New HVAC systems installed as
part of an addition shall comply with Section R403 and with Section M1309
of the International Residential Code.
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Exception: Where ductwork from an existing heating and cooling
system is extended to an addition, Sections R403.3.7 and R403.3.8 shall
not be required.
98. A new Section R502.3 Compliance is added to read as follows:
R502.3 Compliance. An addition shall be deemed to comply with this code either
where the existing building with the addition complies prescriptively (using the
Component performance alternative), or where the existing building with the
addition does not use more energy than the existing building without the addition
and demonstrates compliance using either Simulated building performance
energy cost or ERI compliance option listed below. Existing building envelope and
energy features shall be determined in accordance with ANSI/RESNET/ICC 301
standard.
Exceptions: Unaltered portions of the existing building or building system are
not required to comply with this code section if at least one of the following is
true:
1. The existing building was constructed to the 2012 International Energy
Conservation Code or a later version.
2. The addition is less than 30% of the total conditioned floor area of the
existing building.
3. The building has undergone documented energy efficiency upgrades
to the envelope within the last 10 years.
99. A new Section R502.3.1 Existing plus addition (Prescriptive compliance) is
added to read as follows:
R502.3.1 Existing plus addition (Prescriptive compliance). Component
performance alternative compliance verification completed in accordance with
Section R402.1.5 shall demonstrate that the existing building plus the addition,
has a total thermal conductance that is less than or equal to the total thermal
conductance of the existing building prior to the addition. This method requires
the project to create two Component performance alternative compliance
verification reports as outlined in Section R502.3.1.1.
100. A new Section R502.3.1.1 Reporting is added to read as follows:
R502.3.1.1 Reporting. The following are required at time of permit
application submittal:
1. A Component performance alternative compliance benchmark report
of the existing structure prior to construction.
2. A Component performance alternative compliance report of the
existing building, plus the addition based on the proposed design.
101. A new Section R502.3.2 Existing building plus addition compliance
(Simulated Building Performance) is added to read as follows:
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R502.3.2 Existing building plus addition compliance (Simulated Building
Performance). Simulated building performance compliance verification
completed in accordance with Section R405 shall demonstrate that the existing
building plus the addition uses no more energy than the existing building did
prior to the addition. This method requires the project to create cost compliance
verification reports at three stages as outlined in Section R502.3.2.2.
102. A new Section R502.3.2.2 Reporting is added to read as follows:
R502.3.2.2 Reporting. The following are required at time of permit
application submittal:
1. A baseline Simulated building performance cost compliance report
of the existing structure prior to construction.
2. A projected Simulated building performance cost compliance report
of the existing building plus the addition based on the proposed
design for the building in its entirety.
For Certificate of Occupancy, a final confirmed Simulated building
performance cost compliance report shall be submitted prior to final
inspection.
103. A new Section R502.3.3 Existing plus addition compliance (Energy Rating
Index (ERI) Alternative) is added to read as follows:
R502.3.3 Existing plus addition compliance (Energy Rating Index (ERI)
Alternative). An ERI score shall demonstrate that the existing building plus
the addition uses no more energy than the existing building did prior to the
addition. This method requires the project to obtain an ERI score at three
stages as outlined in Section R502.3.3.1.
104. A new Section R502.3.3.1 Reporting is added to read as follows:
R502.3.3.1 Reporting. For permitting, the following are required:
1. A baseline ERI score of the existing structure prior to construction.
2. A projected ERI score of the existing building plus the addition
based on the proposed design for the building in its entirety.
For Certificate of Occupancy, a confirmed ERI report shall be submitted
prior to final inspection.
105. A new Appendix RZ Residential Performance Path to Zero Carbon Building
is added to read as follows:
APPENDIX RZ
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RESIDENTIAL PERFORMANCE PATH TO ZERO CARBON BUILDING
SECTION RZ101
GENERAL
RZ101.1 Purpose. This appendix provides requirements to be applied over the
course of the 2024, 2027, and 2030 code cycles that will result in all new residential
buildings reaching zero carbon by the 2030 code. Appendix RZ is specifically for new
residential buildings as defined in Chapter 2. The Zero Carbon Residential Building
Provisions are designed to work with residential occupancies where the Energy
Rating Index (ERI) can be applied including one- and two-family dwellings and
townhouses as well as Group R-2, R-3 and R-4 buildings three stories or less in
height above grade plane. This appendix is not intended to apply to existing building
projects as the ERI values used in the appendix were determined based on analysis
for new construction building projects.
RZ101.2 Scope. New residential buildings shall comply with the requirements of this
appendix.
RZ101.3 Application. Residential buildings shall comply with Section R406 except
as amended by this appendix.
Exception: Additions, alterations, repairs and changes of occupancy to existing
buildings complying with Chapter 5.
RZ101.4 Certificate. A permanent certificate shall be completed by the builder or
other approved party and posted on a wall in the space where the furnace is located,
a utility room or an approved location inside the building. Where located on an
electrical panel, the certificate shall not cover or obstruct the visibility of the circuit
directory label, service disconnect label or other required labels. The certificate shall
indicate the following:
1. The predominant R-values of insulation installed in or on ceilings, roofs, walls,
foundation components such as slabs, basement walls, crawl space walls and
floors and ducts outside conditioned spaces.
2. U-factors of fenestration and the solar heat gain coefficient (SHGC) of
fenestration. Where there is more than one value for any component of the
building thermal envelope, the certificate shall indicate both the value covering
the largest area and the area weighted average value if available.
3. The results from any required duct system and building thermal envelope air
leakage testing performed on the building.
4. The types, sizes and efficiencies of heating, cooling and service water-heating
equipment. Where a gas-fired unvented room heater, electric furnace or
baseboard electric heater is installed in the residence, the certificate shall
indicate “gas-fired unvented room heater,” “electric furnace” or “baseboard
electric heater,” as appropriate. An efficiency is not required to be indicated
for gas-fired unvented room heaters, electric furnaces or electric baseboard
- 68 -
heaters.
5. Where on-site photovoltaic panel systems have been installed, the array
capacity, inverter efficiency, panel tilt and orientation shall be noted on the
certificate.
6. For buildings where an Energy Rating Index score is determined in
accordance with Section R406, the Energy Rating Index score and CO2e
Index, both with and without any on-site generation, shall be listed on the
certificate.
7. The code edition under which the structure was permitted.
8. Where a solar-ready zone is provided, the certificate shall indicate its location
and dimensions.
SECTION RZ102
GENERAL DEFINITIONS
CO2e INDEX. A numerical integer value, calculated in accordance with
ANSI/RESNET/ICC 301, that represents the relative Carbon Dioxide equivalence
(CO2e) emissions of a rated design as compared with the CO2e emissions of the
CO2e reference design, where an Index value of 100 represents the CO2e
performance of the CO2e reference design and an Index value of 0 (zero)
represents a home that emits zero net CO2e annually.
COMMUNITY RENEWABLE ENERGY FACILITY (CREF). A facility that
produces energy from renewable energy resources and that is qualified as a
community energy facility under applicable jurisdictional statutes and rules.
FINANCIAL RENEWABLE ENERGY POWER PURCHASE AGREEMENT
(FPPA). A financial arrangement between a renewable electricity generator and
a purchaser wherein the purchaser pays or guarantees a price to the generator
for the project’s renewable generation. Also known as a financial power purchase
agreement and virtual power purchase agreement.
PHYSICAL RENEWABLE ENERGY POWER PURCHASE AGREEMENT
(PPPA). A contract for the purchase of renewable electricity from a specific
renewable electricity generator by a purchaser of renewable electricity.
SECTION RZ103
ZERO NET ENERGY RESIDENTIAL BUILDINGS
RZ103.1 Scope. This section establishes criteria for compliance using an Energy
Rating Index (ERI) analysis. Such analysis shall be limited to dwelling units. Spaces
other than dwelling units in Group R-2, R-3 or R-4 buildings shall comply with
Sections R402 through R404.
RZ103.2 ERI compliance. Compliance based on the ERI requires that the rated
design meets the requirements indicated within Table R406.2 and Section RZ103.
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RZ103.3 Building thermal envelope. The building thermal envelope shall comply
with Section R406.3.
RZ103.4 Energy Rating Index. The Energy Rating Index (ERI) shall be determined
in accordance with ANSI/RESNET/ICC 301. Where a CREF provides electrical
energy or where electrical energy is provided by a PPPA or FPPA in accordance with
Section RZ103.4.1, the on-site power production (OPP) shall be adjusted in
accordance with Equation RZ-1.
Equation RZ-1 Adjusted OPP = OPPkWh + CREFkWh + PPPAkWh + FPPAkWh
where:
OPPkWh = Annual electrical energy from on-site renewable energy, in units
of kilowatt-hours (kWh).
CREFkWh = Annual electrical energy from a CREF, in kWh.
PPPAkWh = Where not included as OPP, the annual electrical energy
contracted from a PPPA, in kWh.
FPPAkWh = Where not included as OPP, the annual electrical energy
contracted from a FPPA, in kWh.
RZ103.4.1 Renewable energy contract. To receive CREFkWh or PPPAkWh or
FPPAkWh credit, the renewable energy shall be delivered or credited to the building
site under an energy contract with a duration of not less than 15 years. The
contract shall be structured to survive a partial or full transfer of ownership of the
building property. The renewable capacity credited to the dwelling shall not be
credited to any other entity.
RZ103.5 ERI and CO2e Index compliance (replaces Section R406.2). Compliance
based on the ERI and CO2e Index requires that the rated design and as-built dwelling
unit meet all of the following requirements:
1. Maximum ERI values shall be as indicated in Table RZ103.5.
2. Maximum CO2e Index shall be as indicated in Table RZ103.5, and determined
in accordance with ANSI/RESNET/ICC 301. Where a CREF provides
electrical energy or where electrical energy is provided by a PPPA or FPPA in
accordance with Section RZ103.4.1, the on-site power production (OPP) shall
be adjusted in accordance with Equation RZ-2.
Equation RZ-2 Adjusted OPP = OPPkWh + CREFkWh + PPPAkWh + FPPAkWh
where:
OPPkWh = Hourly electrical energy from on-site renewable energy, in units
- 70 -
of kilowatt-hours (kWh).
CREFkWh = Hourly electrical energy from a CREF, in units of kilowatt-hours
(kWh).
PPPAkWh = Where not included as OPP, the hourly electrical energy
contracted from a PPPA, in units of kilowatt-hours (kWh).
FPPAkWh = Where not included as OPP, the hourly electrical energy
contracted from a FPPA, in units of kilowatt-hours (kWh).
Any electrical storage system impacts, including electrical losses, that
adjust the time of delivered renewable energy shall be included .
TABLE RZ103.5 MAXIMUM ENERGY RATING AND CO2e INDEX
Date of adoption of amended IECC Code 2024 2027 b 2030 b
Energy Rating Index (ERI) Not Including Renewable
Energy
50 46 42
CO2e Index Including Adjusted OPPa 50 25 0
a. CO2e values will typically be equal to or lower than ERI values.
b. These are projected ERI and CO2e targets for buildings constructed under the 2027 and 2030 code cycles.
These targets are not required for the 2024 code cycle.
RZ103.6 Verification by approved agency. Verification shall comply with Section
R406.6.
RZ103.7 Documentation. Documentation shall comply with Section R406.7.
RZ103.7.1 Confirmed compliance report for a certificate of occupancy
(replaces Section R406.7.2.2). A confirmed compliance report submitted for
obtaining the certificate of occupancy shall be site- and address-specific and shall
include the following:
1. Building street address or other building site identification.
2. Declaration of ERI and CO2e Index on title page and on building plans.
3. The name of the individual performing the analysis and generating the
report.
4. The name and version of the compliance software tool.
5. Documentation of all inputs entered into the software used to produce the
results for the ERI reference design and the as-built dwelling unit. A final
confirmed certificate indicating that the as-built building has been verified
to comply with Sections R406.2, R406.4 and R406.5. The certificate shall
report the energy features that were confirmed to be in the building,
including component level insulation R-values or U-factors; results from
any required duct system and building thermal envelope air leakage
testing; and the type and rated efficiencies of the heating, cooling,
mechanical ventilation and service water-heating equipment installed. The
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certificate shall report the estimated dwelling unit energy use by fuel type,
inclusive of all end uses.
6. Where on-site renewable energy systems have been installed on or in the
building, the certificate shall report the following:
6.1. Type
6.2. Production size
6.3. The registered ERI value with renewables
6.4. The ERI without renewable energy that complies with Table
RZ103.5 and the rated renewable energy system power.
7. Where off-site renewable energy systems have been installed on or in
the building, the certificate shall report the following:
7.1. The registered CO2e Index without the off-site power
7.2. The CO2e Index that complies with Table RZ103.5 with the
purchased renewable energy.
8. Compliance with RZ103.4.1 shall require submittal of a copy of the
contract for the off-site energy.
SECTION RZ104
REFERENCED STANDARDS
RZ104.1 General. See Table RZ104.1 for standards that are referenced in various
sections of this appendix. Standards are listed by the standard identification with the
effective date, standard title, and the section or sections of this appendix that
reference the standard.
TABLE RZ104.1 REFERENCED STANDARDS
STANDARD ACRONYM STANDARD NAME SECTIONS HEREIN
REFERENCED
ANSI/RESNET/ICC 301
ANSI/RESNET/ICC 301-2022
Standard for the calculation
and labeling of the Energy
Performance of Dwelling and
Sleeping Units using an
Energy Rating Index.
RZ102, RZ103.4, RZ103.5
Section 4. The codifier of the Code of the City of Fort Collins is hereby directed
to amend all existing cross references in the City Code and the Land Use Code in
accordance with the provisions of this ordinance.
Section 5. The City Attorney and the City Clerk are hereby authorized to modify
the formatting and to make such other amendments to this Ordinance as necessary to
facilitate publication in the Fort Collins City Code; provided, however, that such
modifications and amendments shall not change the substance of the Code provisions.
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Introduced, considered favorably on first reading on December 2, 2025, and
approved on second reading for final passage on December 16, 2025.
______________________________
Mayor
ATTEST:
______________________________
City Clerk
Effective Date: December 26, 2025
Approving Attorney: Madelene Shehan
Exhibit: Exhibit A - Notice of Publication
Exhibit B - City of Fort Collins Building Code Residential Air Tightness
Testing Protocol, New Attached and Detached Single Family
Dwellings
Exhibit C - City of Fort Collins New Multifamily Air Tightness Testing
Protocol
NOTICE OF PUBLIC HEARING
NOTICE is hereby given of a public hearing to be held before the Council of the City of
Fort Collins,Colorado,on the 2nd day of December,2025,at 6:00 p.m.,or as soon thereafter as
the matter may come on for hearing,in the Council Chambers at the City Hall,300 LaPorte
Avenue, Fort Collins,Colorado for the purpose of considering the adoption of ordinances that adopt
by reference the 2024 International Building Code,2024 International Residential Code,2024
International Energy Conservation Code,2024 International Mechanical Code,2024
International Fuel Gas Code,2024 International Existing Building Code,2024 International
Swimming Pool and Spa Code,2024 International Property Maintenance Code,and the 2024
International Plumbing Code,each promulgated by the International Code Council,the 2023
National Electrical Code and the 2025 Colorado Wildfire Resiliency Code,together with local
amendments.
Not less than one (I)copy of said Codes has been,and now is on file in the Office of the
City Clerk of the City of Fort Collins and is available for public inspection.
The purpose of adopting the International Building Code,International Residential Code,
International Energy Conservation Code,International Mechanical Code,International Fuel Gas
Code,International Existing Building Code,International Swimming Pool and Spa Code,
International Property Maintenance Code,International Plumbing Code,National Electrical Code, and
the Colorado Wildfire Resiliency Code,with local amendments by said ordinances is to provide for
protection of public health,safety and welfare of the City and its residents.
Individuals who wish to address Council via remote public participation can do so through
Zoom at https://zoom.us/i/98241416497.(The link and instructions are also posted
www.fc ov.com/councilcomments.Individuals participating in the Zoom session should watch
the meeting through that site,and not via FCTV,due to the streaming delay and possible audio
interference.
The City of Fort Collins will make reasonable accommodations for access to City services,
programs and activities,and will make special communication arrangements for persons with
disabilities.Please call (970)221-6515 (V/TDD:Dial 711 for Relay Colorado)for assistance.
This notice is given and published by order of the City of Fort Collins,Colorado.
Dated this /4 day of __________2025.
~
City ~rk
Upon request,the City of Fort Collins will provide language access services for individuals who have
limited English proficiency,or auxiliary aids and services for individuals with disabilities,to access
City services,programs and activities.Contact (970) 221-65 15 (VITDD:Dial 711 for Relay
Colorado)for assistance.Please provide 48 hours advance notice when possible.
A peticiOn,Ia Ciudad de Fort Collins proporcionará servicios de acceso a idiomas para personas que
no dominan el idioma inglés,o ayudas y servicios auxiliares para personas con discapacidad,para
que puedan acceder a los servicios,programas y actividades de Ia Ciudad.Para asistencia,llame al
970.221.6515 (V/TDD:Marque 711 para Relay Colorado).Por favor proporcione 48 horas de aviso
previo cuando sea posible.
EXHIBIT A TO ORDINANCE NO. 212, 2025
EXHIBIT B TO ORDINANCE NO. 212, 2025
City of Fort Collins air tightness testing protocol v4.2 12/16/2025
City of Fort Collins Residential Air Tightness Testing Protocol,
New Buildings or Attached and Detached Single Family Dwellings
Approved Testers
Test results will only be accepted from individuals that hold any of the following certifications:
RESNET Rater or RFI, BPI Building Analyst or BPI IDL, or other building performance professional
approved by the Building Official.
Building or dwelling unit air leakage testing code reference
2024 International Energy Conservation Code (IECC) as amended by the City of Fort Collins.
Section R402.5.1.2 Air leakage testing. Testing is required for all residential energy code
compliance paths and for all residential buildings and dwelling units.
Testing protocol
A multi-point air tightness test shall be conducted based on the ANSI/Residential Energy
Services Network (ANSI/RESNET)/ICC 380, ASTM E779, ASTM E1827 or ASTM E3158.
Compliance requirement
The building or dwelling unit air change rate shall not exceed 3.0 ACH50 or 0.16 CFM per square
foot (sq ft) of dwelling unit enclosure area when tested at a 50 Pascal (Pa) test pressure.
Submittal requirement
Output from the blower door testing / analysis software showing, at a minimum, the following
information:
Building address
Date of test
Test technician* and company conducting the test
Building volume (cubic feet) and/or sq ft of dwelling unit enclosure area that encloses the
building thermal envelope as defined within the IECC.
Building leakage rate at 50 Pa test pressure (corrected CFM50)
Percent uncertainty in the corrected CFM50, at the 95% confidence level (+/- 5%)
Building air change rate at 50 Pa test pressure (ACH50 = CFM50 x 60/volume) or (CFM50 /
sq ft dwelling unit enclosure area)
*The tester must be identified on the software report. This info may be handwritten on the report.
Note
One example of measurement software meeting the requirements above is TECTITE, published by
‘The Energy Conservatory’. TEC software options are available at www.energyconservatory.com.
Attached garage isolation
Isolation testing of attached garages from adjoining conditioned areas shall be verified in accordance
with the following:
Testing protocol
EXHIBIT B TO ORDINANCE NO. 212, 2025
City of Fort Collins air tightness testing protocol v4.2 12/16/2025
Set up the building in accordance with the testing protocol for building or dwelling unit air
leakage above.
Garage doors to the exterior shall be closed.
Place a pressure tap in the garage and close the door between house and garage, without
crimping the sensing tube (recommendation: use rigid metal tube where it passes through
doorway).
Adjust the blower door fan speed such that the building interior is depressurized to -50 Pa
with respect to (WRT) the outdoors.
Measure the house pressure (Pa) WRT the garage.
NOTE: Where tested pressure falls below -45 Pa the tester may proceed with “Open a Door” test
below.
Testing Protocol – Open a Door
Follow the above “Testing Protocol” again and note the Pa WRT garage.
Using the tables below, locate and note the “multiplier” that corresponds to the Pa WRT
garage from above. Ex: if the house Pa WRT garage is 36 the multiplier will be 0.96.
Note the house CFM50 with door from house to garage closed.
Open the door from house to garage and return the building to -50 Pa WRT outdoors making
note of the house CFM50 with door from house to garage open.
Subtract the CFM50 with door from house to garage closed from the CFM50 with door to
garage open.
Multiply the difference between the two CFM50 numbers by the “multiplier” from step two.
If the result is less than or equal to 100 CFM the house WRT garage passes.
Pa WRT garage
(step 1 above) Multiplier
Pa WRT garage
(step 1 above) Multiplier
Pa WRT garage
(step 1 above) Multiplier
44 0.37 34 1.17 24 3.04
43 0.43 33 1.29 23 3.36
42 0.49 32 1.42 22 3.73
41 0.56 31 1.56 21 4.14
40 0.63 30 1.71 20 4.61
39 0.70 29 1.88 19 5.15
38 0.78 28 2.07 18 5.77
37 0.87 27 2.27 17 6.50
36 0.96 26 2.50 16 7.36
35 1.06 25 2.76 15 8.38
Compliance and submittal requirement
The house pressure with respect to the garage shall be in the range of -45 to -50 Pa, or the Open a
Door test shall be less than or equal to 100 CFM. Record the test result on the report using “House
pressure WRT garage = _X_ Pa”. ‘X’ being the pressure measurement. Or record the Open a Door
test result using “Open a Door = _X_CFM”. ‘X’ being the CFM measurement. This may be recorded
within the ‘Comments’ section of TECTITE. Example below.
Rooms containing fuel-burning appliances isolation
Where open combustion air ducts provide combustion air to open combustion fuel-burning
appliances, the appliances and combustion air opening shall be located outside the building thermal
EXHIBIT B TO ORDINANCE NO. 212, 2025
City of Fort Collins air tightness testing protocol v4.2 12/16/2025
envelope or enclosed in a room that is isolated from inside the thermal envelope.
Testing protocol
Set up the building in accordance with the protocol for whole-house air leakage, above.
Place a pressure tap in the mechanical room and close the door between house and
mechanical room, without crimping the sensing tube (recommendation: use rigid metal tube
where it passes through doorway).
Adjust the blower door fan speed to so that the building interior is depressurized to -50
Pascals with respect to the outdoors.
Measure the house pressure with respect to the mechanical room.
Compliance and submittal requirement
The house pressure with respect to the mechanical room shall be in the range of -45 to -50 Pa.
Record the test result on the report using “House pressure WRT mechanical room = _X_ Pa”. ‘X’
being the pressure measurement. This may be recorded within the ‘Comments’ section of TECTITE.
Example below. Natural draft appliances must also pass a Combustion Safety Test.
Example:
City of Fort Collins New Multifamily Air Tightness
Testing Protocol
City of Fort Collins New Multifamily Air Tightness Testing Protocol 12/16/2025
Code reference and application
2024 International Energy Conservation Code (IECC) Sections C402.6.2.2 and R402.5.1.2 as amended
by the City of Fort Collins, requires that stacked multifamily individual dwelling units meet the air tightness
requirement below. It does not apply to attached-single-family dwellings such as duplexes, townhomes,
and rowhouses.
Approved testers
Test results will only be accepted from individuals holding any of the following certifications: RESNET
Rater or RFI, BPI Building Analyst or BPI IDL, or other professional approved by the Building Official.
Compliance requirements
•Apartment exterior air barrier must be continuous and unbroken, separating the conditioned space
of the building from the exterior and any unconditioned spaces or mechanical rooms.
•Units must be compartmentalized to minimize uncontrolled pathways for smoke and other indoor
air pollutants to transfer between units. Walls, ceilings, floors, and doors that separate each
apartment from neighboring apartments, corridors, common space, utility chases, floors above and
below, stairwells and elevator shafts must be air sealed.
•The maximum air leakage rate at 50 Pascal test pressure shall not exceed 0.27 CFM50/square
foot (1.4 L/s m2) of testing / dwelling unit enclosure area as defined within the IECC.
Unit sampling
•Where buildings have fewer than eight testing units, each testing unit shall be tested.
•For buildings with eight or more units, a minimum of seven or 20 percent of the testing units in the
building, whichever is greater, shall be tested, including at least one of each unit type and
approximately an equal number of units on each floor level. For each tested unit that exceeds the
maximum air leakage rate, corrections to the unit must be made and the unit re-tested until it meets
the required air leakage, and an additional two units of this type in the same building shall be tested
and meet the required air leakage.
Testing
•A multi-point air tightness test shall be conducted based on the ANSI/Residential Energy Services
Network (ANSI/RESNET)/ICC 380 ASTM E779, ASTM E1827 or ASTM E3158.
Submittal requirement
Output from the blower door testing / analysis software showing, at a minimum, the following
information:
•Building address, dwelling model unit type and unit number
•Date of test
•Name of test technician and company conducting the test
•Sq ft of dwelling unit enclosure area as defined within the IECC
•Percent uncertainty in the corrected CFM50, at the 95% confidence level (+/- 5%)
•Dwelling unit air change rate (CFM50 / sq ft dwelling unit enclosure area)
Note
An example of measurement software meeting the requirements above is TECTITE, published by ‘The
Energy Conservatory’. TEC software options are available at www.energyconservatory.com.
EXHIBIT C TO ORDINANCE NO. 212, 2025