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HomeMy WebLinkAbout2221 S Timberline Rd - Correspondence/Building Code - 07/14/20059AW Archistruction® July 14, 2005 Mike Gebo City of Fort Collins Building Permits and Inspections 281 North College Avenue Fort Collins, CO 80522-0580 Fort Collins P.O. Box 2127 (80522) 2620 E. Prospect Road, Suite 100 Fort Collins, CO 80525 (970)493-8747 (970) 493-5869 FAX RE: Fort Collins Police Services Facility Dear Sir: Denver Eighteenth Street Atrium 1621 18th Street, Suite 250 Denver, CO 80202 (303) 296-0383 (303) 296-0382 FAX t50(oo0 2 Z Z Z) S • fil l�'I l 1.1 � Colorado Springs P.O. Box 1478 Colorado Springs, CO 80901-14 78 (719)633-4713 (719) 633-9508 FAX r—TS, The Police Services Building will be a 3-story, 97,663 square foot fully sprinklered building. Per the 1997 UBC (United Building Code) this can be built as a Type II-1 hour building with an allowable area of 144,000 square feet. However per the 1997 UBC Section 402.1 states that if a building is sprinklered it is allowed to have an atrium and if there is an atrium then per Section 505.3 the sprinkler cannot be used to increase the allowable area of a building. This same building could be built under the 2003 IBC as a Type II-B (non -rated) construction with an allowable area of 241,500 square feet with a 3-story atrium. The exclusion for area increase due to having an atrium has been removed from the 2003 IBC and appears that the atrium requirements have not changed significantly (see attached `Atriums' code comparison) from the 1997 UBC. It is apparent that the redundancy required around the atrium / sprinkler issue from the 1997 UBC has been deemed not necessary by the new 2003 IBC (section 506.3 Automatic sprinkler system increase), therefore we are requesting that all code requirements from the 1997 UBC continue to be adhered to with the exception that Item no.4 in section 505.3 not be enforced on this project allowing the new facility to be jL!T ilt as a Type 11-1 hour building. This change will not affect the already agreed upon conditions of the entire building being reviewed as a B Occupancy with the following exceptions: 1. The Detention/ Holding Area will still need to meet all requirements for the 1-3 occupancy, including construction type and occupancy separation from the B occupancy. 2. Exiting for all areas within the building will be based on the uses/occupancies determined by the building department in the June 9`r' pre -submittal meeting. Please call me with any questions on this request for review at 495-6309. Thank you again for your continued cooperation in resolving these matters. Respectfully miffed, Chris Wesche Project Architect I OF 4 ATRIUMS General 1997 UBC 402.1 General. Buildings, of other than Group H Occupancy, with automatic sprinkler protection throughout may have atria complying with the provisions of this section. Such atria shall have a minimum opening area and dimension as set forth in Table 4-A. 2003IBC 404.1 General. Vertical openings meeting the requirements of this section are not required to be enclosed in other than Group H occupancies. 404.1.1 Definition. The following word and term shall, for the purposes of this chapter and as used elsewhere in this code, have the meaning shown herein. ATRIUM. An opening connecting two or more stories other than enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or other equipment, which is closed at the top and not defined as a mall. Stories, as used in this definition, do not include balconies within assembly groups or mezzanines that comply with Section 505. 404.2 Use. The floor of the atrium shall not be used for other than low fire hazard uses and only approved materials and decorations in accordance with the International Fire Code shall be used in the atrium space. Exception: The atrium floor area is permitted to be used for any approved use where the individual space is provided with an automatic sprinkler system in accordance with Section 903.3.1.1. [F] 404.3 Automatic sprinkler protection. An approved automatic sprinkler system shall be installed throughout the entire building. Exceptions: 1. That area of a building adjacent to or above the atrium need not be sprinklered provided that portion of the building is separated from the atrium portion by a 2-hour fire barrier wall or horizontal assembly or both. 2. Where the ceiling of the atrium is more than 55 feet (16 764 mm) above the floor, sprinkler protection at the ceiling of the atrium is not required. Smoke Control 1997 UBC 402.2 Smoke -control System. A smoke -control system meeting the requirements of Section 905 shall be provided within the atrium and areas open to the atrium. The smoke -control system shall operate automatically upon actuation of the automatic sprinkler system within the atrium or areas open to the atrium and as required by Section 905.9. 2003IBC 404.4 Smoke control. A smoke control system shall be installed in accordance with Section 909. Exceptions: (Not applicable) 1. Smoke control is not required for floor openings meeting the requirements of Section 707.2, Exception 2, 7, 8 or 9. 2. Smoke control is not required for floor openings meeting the requirements of Section 1019.1, Exception 8 or 9. New code has the addition of section 909.20 smoke enclosures, and the minor verbiage change in 909.8.1 that adds, "which forms a portion of a required egress system" in sentence 1. This section also adds the last sentence that deals with the temperature of the make up air. Both of these additions to this section 909.8.1 are minor and would not affect this project. Z oy 4 Enclosure of atriums 1997 UBC 402.3 Enclosure of Atria. Atria shall be separated from adjacent spaces by not less than one -hour fire -resistive construction. EXCEPTIONS: 1. The separation between atria and tenant spaces that are not guest rooms, congregate residences or dwelling units may be omitted at three floor levels. 2. Open exit -access balconies are permitted within the atrium. Openings in the atrium enclosure other than fixed glazing shall be protected by smoke- and draft -control assemblies conforming to Section 1004.3.4.3.2. EXCEPTION: Other tightfitting doors that are maintained automatic closing, in accordance with Section 713.2, by actuation of a smoke detector, or self -closing may be used when protected as required for glazed openings in Exception 2.Fixed glazed openings in the atrium enclosure shall be equipped with fire windows having a fire - resistive rating of not less than three -fourths hour, and the total area of such openings shall not exceed 25 percent of the area of the common wall between the atrium and the room into which the opening is provided. 2003IBC 404.5 Enclosure of atriums. Atrium spaces shall be separated from adjacent spaces by a 1-hour fire barrier wall. EXCEPTIONS: 1. A glass wall forming a smoke partition where automatic sprinklers are spaced 6 feet (1829 mm) or less along both sides of the separation wall, or on the room side only if there is not a walkway on the atrium side, and between 4 inches and 12 inches (102mmand 305 mm) away from the glass and so designed that the entire surface of the glass is wet upon activation of the sprinkler system. The glass shall be installed in a gasketed frame so that the framing system deflects without breaking (loading) the glass before the sprinkler system operates. 2. A glass -block wall assembly in accordance with Section 2110 and having a 3/4-hour fire protection rating. 3. The adjacent spaces of any three floors of the atrium shall not be required to be separated from the atrium where such spaces are included in computing the atrium volume for the design of the smoke control system. 402.4 Escalators and Elevators. Escalators and elevators located entirely within the atrium enclosure need not be enclosed unless required by Chapter 30 Egress 1997 UBC 402.5 Means of Egress. 402.5.1 Travel distance. Not more than 100 feet (30 480 mm) of the travel distance allowed by Section 1004.2.5 may be on an open exit -access balcony within the atrium. 402.5.3 Stairs and ramps. Stairways and ramps in the atrium space shall be enclosed. EXCEPTIONS: 1. Stairs and ramps not required for egress need not be enclosed. 2. Stairs and ramps connecting only the lowest two floors in the atrium space need not be enclosed. 3. Stairs and ramps connecting floor levels within a story need not be enclosed. 402.6 Occupancy Separation Exceptions. The vertical portion of the occupancy separation that is adjacent to the atrium may be omitted between a Group B Occupancy office, Group M Occupancy sales area or Group A, Division 3 Occupancy and Group R, Division 1 apartment, congregate residence or guest room located on another level. 2003IBC 404.8 Travel distance. In other than the lowest level of the atrium, where the required means of egress is through the atrium space, the portion of exit access travel distance within the atrium space shall not exceed 200 feet (60 960 mm). 3 -0f 4 2 Power 1997 UBC 402.7 Standby Power. Smoke control for the atrium and the smoke -control system for the tenant space shall be provided with standby power as required in Section 905.8. 905.8 Power Systems. 905.8.1 General. The smoke -control system shall be supplied with two sources of power. Primary power shall be the normal building power systems. Secondary power shall be from an approved standby source complying with the Electrical Code. The standby power source and its transfer switches shall be in a separate room from the normal power transformers and switchgear and shall be enclosed in a room of not less than one -hour fire -resistive construction, ventilated directly to and from the exterior. Power distribution from the two sources shall be by independent routes. Transfer to full standby power shall be automatic and within 60 seconds of failure of the primary power. The systems shall comply with the Electrical Code. 905.8.2 Power sources and power surges. Elements of the smoke -management system relying on volatile memories or the like shall be supplied with uninterruptable power sources of sufficient duration to span 15-minute primary power interruption. Elements of the smoke -management system susceptible to power surges shall be suitably protected by conditioners, suppressors or other approved means. 2003IBC 404.6 Standby power. Equipment required to provide smoke control shall be connected to a standby power system in accordance with Section 909.11. 909.11 Power systems. The smoke control system shall be supplied with two sources of power. Primary power shall be the normal building power systems. Secondary power shall be from an approved standby source complying with the ICC Electrical Code. The standby power source and its transfer switches shall be in a separate room from the normal power transformers and switch gear and shall be enclosed in a room constructed of not less than 1-hour fire -resistance -rated fire barriers ventilated directly to and from the exterior. Power distribution from the two sources shall be by independent routes. Transfer to full standby power shall be automatic and within 60 seconds of failure of the primary power. The systems shall comply with the ICC Electrical Code. 909.11.1 Power sources and power surges. Elements of the smoke management system relying on volatile memories or the like shall be supplied with uninterruptable power sources of sufficient duration to span a 15-minute primary power interruption. Elements of the smoke management system susceptible to power surges shall be suitably protected by conditioners, suppressors or other approved means. Interior Finishes 1997 UBC 402.8 Interior Finish. The interior finish of walls and ceilings of the atrium and all unseparated tenant spaces allowed under Exception 1 to the first paragraph of Section 402.3 shall be Class I with no reduction in class for sprinkler protection. 2003IBC 404.7 Interior finish. The interior finish of walls and ceilings of the atrium shall not be less than Class B with no reduction in class for sprinkler protection. Smoke Control Testing 1997 UBC 402.9 Acceptance of the Smoke -control System. Acceptance shall be as required by Section 905.15. 2003IBC [F] 909.18 Acceptance testing. Devices, equipment, components and sequences shall be individually tested. These tests, in addition to those required by other provisions of this code, shall consist of determination of function, sequence and, where applicable, capacity of their installed condition. 4 4 3