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HomeMy WebLinkAboutWOODLAND PARK PUD - FINAL - 19-94C - CORRESPONDENCE - CITY STAFFFort Collins residential energy code ENERGY SCORE required to comply using systems analysis path February 1997 Conditioned floor areas Required ENERGY SCORE Min Max Gas heat Elec heat 0 500 G-73 E-63 501 1000 G-75 E-65 1001 1500 G-76 E-66 1501 2000 G-77 E-68 2001 2500 G-79 E-69 2501 3000 G-80 E-71 3001 3500 G-81 E-73 3501 4000 G-83 E-74 Greater than 4000 G-84 E-76 NOTES: For complete information, see "Systems analysis energy code compliance using ENERGY SCORE," available from City of Fort Collins Building and Zoning (221-6760: Combinations of gas heat + electric WH or electric heat + gas WH are not covered by table above. systhreshmbl/SS23 -- 2110/97 Inspection: B+Z inspectors will do all the normal inspections. ENERGY SCORE raters will only be looking at features needed to complete the energy ratings. Stock plans: You may have stock plans energy -rated to comply via systems analysis. In rating the stock plan, it is recommended that the rater check compliance with the home in "worst -case" condition -- typically with the maximum amount of glazing, facing away from south. If this complies, approaches with less glazing and more of it south -facing should also comply. Once the basic data has been collected, it is easy for the rater to look at the home in several different orientations. B+Z requires a rating specific to a given address to be submitted in order to receive a building permit. You should make arrangements with the rater to modify the rating as needed each time you build from the stock plan. Note that the $50 Light and Power rating fee assistance applies only to the initial stock plan rating, not to specific addresses at which the plan is built. Multi -family ratings: ENERGY SCORE is designed to rate individual units in a multi -family complex, rather than full buildings. To get a building permit, each unique individual unit must be rated, in "worst -case" orientation (minimum solar gains). Site rating requirements will be determined by B+Z for each particular project -- there is no need to check every unit and, if the energy specs are consistent, there may be no need to check every building, either. Prescriptive measures still required: The following measures are required for both the prescriptive and systems analysis paths: — All insulation must be installed in accordance with the "Insulation Guidelines" published by Building and Zoning. — All crawl spaces must have a moisture retarder on the ground, max perm rating 1.0. — Crawl spaces must be built with consistency between insulation, venting and air sealing approaches, following one of these choices: • "Warm," unvented crawl space, inside the insulation boundary: perimeter walls insulated, no venting, sealed at perimeter wall like basement, no requirements for insulating or sealing crawl space ductwork or piping. • "Cold" crawl space, outside the insulation boundary: floor above crawl space and any walls to conditioned space insulated, venting optional, floor above and any walls to conditioned space sealed, ductwork and piping in crawl space insulated and sealed. — All mechanical equipment must be installed in accordance with manufacturer's instructions. — All ductwork must meet Uniform Mechanical Code requirements. Ductwork passing through unconditioned space must be sealed using mastic and mesh or other approved materials. — Water heater piping near the tank must have one of the following two options, on both hot and cold plumbing: ° Heat trap valves or loops at the tank. • Minimum 1" pipe insulation on first 8' of pipe. — Combustion air must be provided in accordance with Building and Zoning requirements. — Disclosure forms for insulation and mechanical systems must be provided. Where do I get more information? • For code compliance questions, contact Building and Zoning at 221-6760. • For ENERGY SCORE questions, contact Light and Power at 221-6700. sysfact2.doc/WP49 -- 5/6/97 with Energy -Rated Homes of Colorado and the Home Builders Association of Northern Colorado to approve the E-StarTm rating program as another compliance alternative. The procedure described here is based on the ENERGY SCORE program. The E-StarTM procedures are anticipated to be quite similar -- details will be announced when available. • Qualifying scores: ENERGY SCORE rates homes on a 0-to-100 point scale, based on projected energy use for space heating and water heating. The higher the score, the more efficient the home. Electric and gas -heated homes are rated on separate scales, designated "E" and "G" (scores on the two scales are not directly comparable). The scores that homes must attain to comply with code under the systems analysis path are shown on the attachment. Note that larger homes must attain higher scores. "Conditioned floor area" is based on ENERGY SCORE definitions and includes basement floor area. • Certified raters: ENERGY SCORE ratings are done by independent raters trained and certified by the city. Call City of Fort Collins Light and Power for a current list. Raters set their own fee schedules. You're encouraged to call more than one to compare costs and services. • Rating cost assistance: At this time, City of Fort Collins Light and Power is still offsetting $50 of the rating cost for all ratings within city limits. This is handled directly between the city and the rater, so all you need to pay is the net cost. There will be one $50 credit for a given address or stock plan. Beginning 6/1/97, City of Fort Collins Building and Zoning also provides a $75 permit fee reduction for homes for which energy code compliance is documented using the ENERGY SCORE systems analysis approach. • Plan and site ratings: Two ratings are required at different stages. To get a building permit, a preliminary rating is required based on building plans and specs. It must meet the qualifying score threshold. When the home is built, a final site inspection and rating is required to verify that the as -built home meets the qualifying score threshold. This is a condition for receiving a Certificate of Occupancy. Typically the same rater does both ratings. Discuss timing requirements with the rater so these steps won't delay your project. • Testing alternative approaches: Once the basic rating has been completed on a set of plans, alternative specs can be analyzed. The attached example shows about a dozen different combinations of insulation specs, window type and orientation, air sealing, and equipment efficiency. You can work with the ENERGY SCORE rater to test these alternatives, or you can obtain the ENERGY SCORE software from Light and Power and do it yourself ($15 for software and manual). • Information required: To do the rating, the rater needs to know all of the planned energy specifications. B+Z also requires a list of the energy features that were assumed to produce the plans rating being submitted for code compliance. These specifications should be documented on the plans, in a general spec list, or in an energy spec list available from the ENERGY SCORE rater or B+Z. • Air leakage: Unlike the prescriptive code, the systems analysis approach has no specific airtightening requirements or target. ENERGY SCORE simply requires an estimate of air leakage to calculate the energy performance of a home. ENERGY SCORE provides two options: visual observation or blower door testing. Using visual observation, the rater will inspect approximately 20 components and use a worksheet to estimate the air leakage rate. Because of the uncertainties involved, the minimum rate that may be entered is 0.40 air changes per hour (corresponding to about ACH50 = 6.8). A lower number can only be entered if a blower door test justifies it. The test must be conducted in accordance with the "Blower Door Test Procedures" available from B+Z. Fort Collins residential energy code "Systems analysis" energy code compliance using ENERGY SCORE May 1997 What is "systems analysis?" There are two ways to comply with the residential energy code: prescriptive path or systems analysis path. The prescriptive path has specific requirements for each building component (example: R-38 ceilings, 78% efficient gas furnace). It is a "cookbook" approach to meeting the code with limited options. The systems analysis path, in contrast, offers a high degree of flexibility to reach the same result. A home complying under the systems analysis path may include any combination of energy efficiency measures which, as a system, result in the same overall efficiency level that would occur if the home were built to the prescriptive path requirements. This allows tradeoffs in efficiency among components and encourages builders to meet code in a manner compatible with their clients' preferences. You choose which path to follow. Certain measures must be implemented regardless of which compliance path is used. Why should I be interested? For typical homes, the prescriptive path is the simpler path. The systems analysis path is typically chosen for one of the following reasons: • You prefer not to use a particular measure required in the prescriptive path and can compensate by increasing the efficiency somewhere else (example: you prefer not to install basement wall insulation). • You are planning to exceed the prescriptive code requirement for a particular component and want to get credit for it so that you can install a less efficient measure somewhere else (example: you're planning to install a 90% efficient furnace, exceeding the prescriptive 78% requirement). • You plan to incorporate a feature not recognized in the prescriptive code and want to get credit for it so that you can install a less efficient measure somewhere else (example: the home will have better than average passive solar gains). • You would like to get a fringe benefit (example: homes meeting code may qualify for Energy Efficient Mortgage incentives). How does it work? Compliance using the systems analysis path must be documented using energy calculation software and procedures approved by Building and Zoning. At the time of this writing, the City's ENERGY SCORE home energy rating software is approved. Building + Zoning is also working Thanks for your inquiry. Sine ely, Ci Doug Swartz Energy Services Engineer cc: Ted Shepard, City of Fort Collins Current Planning Dick Valdez, City of Fort Collins Building and Zoning dks50\richmond.doc -- 1/8/98 & Power I QG\ ` 1 TI City of Fort Collins 8 January 1998 Ms. Wendy Marino Richmond American Homes 4600 S. Ulster St., S. 400 Denver, CO 80237 Dear Wendy: q0 f Vol Enclosed are the materials we discussed today on the phone regarding the ENERGY SCORE home energy rating program for new construction. To reiterate, two requirements apply to your project, given that it is built in Woodland Park Estates PUD: l . To gain approval for the project, the developer made a commitment that all homes built in the PUD would achieve a score of G-80 or above. There are holds on both the building permits and Certificate of Occupancies until the condition has been satisfied. This requirement is administered by the city's Current Planning department, contact Ted Shepard at970-221-6343. 2. All new homes must meet the city's energy code requirements, either by following a prescriptive approach or using ENERGY SCORE as a systems analysis approach to document compliance (the state's Energy Rated Homes of Colorado rating could also be used). Energy code requirements are administered by the city's Building and Zoning department at 970-221-6760 -- you mentioned you'd already spoken with Dick Valdez. I recommend you use ENERGY SCORE to show that the homes are meeting both requirements. You'll be paying for an ENERGY SCORE already for the first requirement, and using it for the second requirement will save you $75 on permit fees. For either requirement, you'll need both a rating from plans (to get your permit) and a rating on site when the home is complete (to get your C.O.). Plan ahead with the rater so that you don't run into a timing crunch. As we discussed, you can take advantage of the fact you're building several homes from each stock plan. You should only need to get each stock plan rated once at plans stage. You must be able to show the home will pass in "worst case" orientation -- i.e. with the home oriented so that the passive solar contribution is the least. All other orientations will then also pass. A site rating will be required on every unit when it is completed. See the enclosed information for more details. Contact the people listed above with questions on compliance. I can help you out with questions on the energy rating process. 700 Wood Street • P.O. Box 580 • Fort Collins, CO 80522-0580 • (970) 221-6700 • FAX (970) 221-6619 • TDD (970) 224-6003 e-mail: light-power@ci.fort-collins.co.us