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HomeMy WebLinkAboutPACIFIC COAST SUPPLY WAREHOUSE - FDP200019 - SUBMITTAL DOCUMENTS - ROUND 1 - FIRE AUTHORITY REQUIREMENTS12364 West Alameda Parkway, Suite 135, Lakewood, Colorado 80228 ● 303-985-3300 ● Fax 303-985-5594 ● www.veritasfire.com July 31, 2020 Poudre Fire Authority 102 Remington Street Fort Collins, CO 80524 Attn: James Lynxwiler Re: Pacific Coast Supply 1012 NE Frontage Road Fort Collins, CO Subject: Fire Protection Requirements and Water Supplies Dear James: Veritas Fire Engineering has been engaged by the Owner and Architect to provide assistance on the fire protection aspects of the project referenced above. As the project is still in the initial stages, it is our goal of securing a fire protection and water supply for the facility that will meet the acceptance of Poudre Fire Authority as well as the needs of the Client. This analysis will follow the requirements of the 2018 International Fire Code (IFC) with Poudre Fire Authority amendments and the 2016 edition of NFPA 13, Standard for the Installation of Sprinkler Systems. Background: The proposed storage building a 20,000 square foot metal building, Type IIB construction, semi conditioned. The building is constructed as a simple gable roof with an eave height of 24’-0” above grade, with the peak at 34’-7” above grade, a 2:12 pitch. Building is considered an S-2 occupancy for the storage of construction drywall sheets up to 12 feet above finished floor maximum in a solid pile arrangement using drywall blocking between lifts and on the floor for fork placement. The south side of the building will have a non-combustible awning for temporary outside storage. The building will be “semi-conditioned”, which will require a dry pipe sprinkler system to prevent freezing. The sprinkler riser room will be heated as required by Code. There is no available adequate water supply for the required fire flow and fire sprinkler system currently on site. There is an existing 2” water line available for domestic use only on site. Fire Suppression: Fire Sprinkler requirements: Poudre Fire Authority amendments require S-2 occupancies over 5,000 square feet in area to be protected by a NFPA 13 fire suppression system (IFC 903.2.10). A warehouse of this type with up to 12 feet of storage will typically have the Hazard classification in NFPA 13 as an Ordinary Hazard Group 2. Assuming a dry system, the required density area would be a .20 gpm/sf/1950 square feet. Since the roof slope is 2:12, a roof slope increase would not be required. This system will require approximately 470 gpm sprinklers, including overage, with an additional 250 gpm hose stream, or 720 gpm. In accordance with 2016 NFPA 13 Table 11.2.3.1.2, an Ordinary Hazard system requires a duration of 60 minutes, assuming that the system is electrically supervised at an approved location. This will require a total water supply of 43,200 gallons of stored water. This system can also provide a density that will allow for storage of Class I-IV commodities up to 12 feet high, if desired in the future. Pacific Coast Supply July 31, 2020 Fire Flow requirements: Appendix B: Using Appendix B of the IFC as adopted by Poudre Fire Authority for fire flow requirements will yield the following result: IFC Table B105.1(2) for a 20,000 square foot Type IIB building requires a fire flow of 3,000 gpm at 20 psi for a period of 3 hours. A reduction of up to 50%, as approved, is allowed when the building is provided with an approved automatic sprinkler system (B105 Exception), but no less than 1,500 gpm. Therefore the minimum fire flow requirement for this building would be (1500 x 180) - 270,000 gallons of water in accordance with Appendix B. Section B103.1 Decreases – The fire chief is authorized to reduce the fire flow requirements or isolated buildings or a group of buildings in rural areas or small communities where the development of full fire flow requirements is impractical. NFPA 1142: Using the 2017 edition of NFPA 1142, Standard on Water Supplies for Suburban and Rural Fire Fighting, which provides a method of determining minimum requirements for alternate water supplies, the calculation is as follows, assuming no exposure hazards, from Section 4.2.1 - WSmin=VStot * CC/OHC = VStot = (200 * 100 * 24) + (50 * 10.7 * 200)= (480000) + (107000) = 587,000 cubic feet Volume CC is .75 for a Type II building (Table 6.2.1) OHC is a 4 for Building Materials supply storage WS = 587000 * .75/4 = 110,000 gallons of water supply This standard also allows the reduction of water supply if the building is sprinklered (NFPA 1142 Section 4.4.1). Conclusions: It is the Owner’s desire to satisfy the requirements of Poudre Fire Authority, however for this type of building and commodity, which is non-combustible building with a non-combustible commodity, a water supply in these ranges for fire flow seem onerous and excessive. In addition to the water storage requirements, a fire pump and enclosure will also be required to achieve the proper pressure for supplying these systems. In lieu of the fire flow requirements above, we would prefer to provide the water necessary for the fire sprinkler system and associate hose stream only. The design would utilize an underground tank to alleviate heating and pad requirements involved with above ground tanks, and utilize a vertical turbine electric fire pump sitting over the tank in a heated enclosure. If acceptable to Poudre Fire Authority, we would propose to use a single 50,000 gallon underground tank, which is the largest size available (without manifolding), to supply the fire suppression system in the building, which includes a hose stream demand of 250 gpm for 60 minutes. We anticipate the pump will be a 750 gpm fire pump at approximately 60 psi to operate the sprinkler system. The pump house will have 3 – 2.5” outlets for testing of the pump or for fire department use in lieu of a separate hydrant due to its proximity to the building. Please review our proposed solution for possible acceptance by PFA for this project. We would appreciate any comments or concerns you may have. Pacific Coast Supply July 31, 2020 Don’t hesitate to contact me if you have any questions or need further clarification. Sincerely, Kenneth Sutton, P.E. Sr. Fire Protection Engineer Veritas Fire Engineering, Inc. 303-985-3300 x211 ken@veritasfire.com