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12 SOUTH MASON - NARRATIVE NEW RESIDENTIAL SPRINKLER SYSTEM AT 12 SOUTH MASON STREET (BUILDING 3) SALEM, MASSACHUSETTS FIRE PROTECTION DESIGN NARRATIVE June 1st, 2020 Prepared For: Village Fire protection 86 Milford Street Milford, New Hampshire (603) 672-6267 Prepared By: P.O. Box 1234 Lynnfield, Massachusetts (781) 389-7999 06-01-2020 New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 ii TABLE OF CONTENTS SECTION PAGE TABLE OF CONTENTS ii INTRODUCTION AND BUILDING DESCRIPTION 1 CODE REVIEW / HAZARD CLASSIFICATION 1 SPRINKLER SYSTEM DESCRIPTION 2 HYDRAULIC CALCULATIONS: 2 FLOW TEST RESULTS: 3 ACCEPTANCE TESTING 3 MAINTENANCE TESTING 3 APPENDIX A – HYDRAULIC CALCULATIONS 4 New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 1 INTRODUCTION AND BUILDING DESCRIPTION The purpose of this Fire Protection Design Narrative is to describe the proposed automatic sprinkler system for the 6-unit residential building “Building 3” located within the 12 Mason Street development in Salem, Massachusetts. Building 3 will consist of an unheated crawlspace extending below the entire building and three levels of residential living space above. The six (6) residential units are arranged in townhouse style with independent entrances. There are no attic spaces or concealed combustible spaces within the building. Through conversations with the Salem Building and Fire Departments, the inaccessible crawlspace will be fenced in and will not be considered part of the aggregate floor area of the building, resulting in the total square footage being below 12,000 SF in gross area. This sprinkler system will consist of a single-zoned wet-pipe sprinkler system designed and installed in accordance with the requirements of NFPA 13R (2013 Edition) and the 9th Edition of the Massachusetts State Building Code (780 CMR, Chapter 9). CODE REVIEW / HAZARD CLASSIFICATION The Sprinkler system and fire alarm system will be in accordance with all applicable codes and standards including: · Massachusetts General Laws (Chapter 148: Fire Prevention) · Board of Fire Prevention and Regulation (527 CMR Chapter 24: Fire Warning Systems installed in Buildings within the Commonwealth of Massachusetts) · NFPA 13R (2013 Edition) · The Massachusetts State Building Code (780 CMR Chapter 9, 9th Edition) The Massachusetts State Building Code (780 CMR Chapter 9, 9th Edition) classifies this building as Type R-2 construction (Section 310.1). Section 903.2.8 (780 CMR Chapter 9, 9th Edition) requires buildings of Use Group R to be provided with an automatic sprinkler system designed and installed in accordance with 780 CMR 903.3. Since the building contains three units and is less than 12,000 sf in gross area with a single means of egress, the sprinkler system has been designed in accordance with the requirements of NFPA 13R (2013 Edition). This system shall be monitored in accordance with the requirements of the 9th Edition of the IBC (780 CMR) and as accepted by the Salem Fire and Building Departments. The fire alarm system will be designed by others. New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 2 SPRINKLER SYSTEM DESCRIPTION A new 4” fire service shall be designed, flushed, tested and installed in accordance with the requirements of NFPA 24 (2013 Edition). The fire service will rise up into a heated sprinkler room, constructed at the end of the new addition. The sprinkler contractor will provide a 4” x 2 ½” reducing code, 2 ½” backflow preventer, 2 ½” straight-pipe riser with vane-type flow switch, pressure gauge and combination 1 ½” test & drain. The sprinkler contractor shall provide a 4” fire department connection with check valve and ball drip. The fire department connection will be located on the face of the building as indicated. Sprinkler Contractor shall coordinate type and location of the FDC with the Salem FD prior to installation. The sprinkler contractor will install residential pendent and sidewall heads as indicated on the associated sprinkler drawings. All sprinklers will be installed in accordance with their listing and the requirements of NFPA 13 (2013 Edition). All sprinkler piping shall be UL Listed CPVC sprinkler piping. All piping shall be installed in accordance with the requirements of NFPA 13 (2013 Edition) and the requirements of the manufacturer. Sprinkler contractor may select any UL listed sprinkler heads provided that the flow and pressure characteristics are the same as the heads used in this design. The CPVC sprinkler risers will be field-verified by the installing contractor. The pendent sprinkler heads will be fed from 1” CPVC branchlines running through wood joists and walls as necessary. It is the general contractor’s responsibility to provide sufficient insulation above any water-filled sprinkler piping to prevent freezing. NOTE: Per the requirements of the Massachusetts State Fire Marshall, all sprinkler contractors installing CPVC piping for automatic sprinkler systems shall be certified by a CPVC representative. NOTE: All sprinkler piping installed in this building shall be installed in conditioned spaces. The building owner is responsible for maintaining appropriate heat within all areas containing sprinkler piping to prevent freeze-ups. Any areas of concern shall be brought to the attention of JFP Solutions, Inc. in writing, prior to installation. The sprinkler contractor shall be responsible for selecting the proper length of all dry-sidewall sprinklers based on the manufacturer’s requirements to prevent freeze-ups. JFP Solutions, Inc. and the engineer of record take no responsibility for any freeze- ups on this sprinkler system. NOTE: Sprinkler head locations have not been coordinated with ceiling-mounted obstructions or soffits. Installing sprinkler contractor shall be responsible for coordinating locations of sprinkler heads with other trades in-field in accordance with the requirements of NFPA 13r (2013 Edition). The addition of soffits or other ceiling-mounted obstructions may result in additional sprinkler heads being required at the owner’s expense. New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 3 HYDRAULIC CALCULATIONS Per the requirements of NFPA 13R (2013 Edition), the four (4) hydraulically most remote residential sprinklers were included in the residential calculations. The system was designed to provide a minimum density of 0.05 gpm/sf and including an outside hose stream allowance of 100 gpm. Hydraulically remote areas, design requirements and associated calculation results are indicated on the associated sprinkler drawings and copies of the calculations are attached to this narrative report in Appendix A. FLOW TEST RESULTS: A Hydrant Flow Test was performed on South Mason Street on March 16th, 2018 utilizing the hydrant at the corner of South Mason and Buffum Street Ext. and the Hydrant on the corner of South Mason and Waters Street. The results of the flow test are as follows: Static Pressure: 80 PSI Residual Pressure: 60 PSI Recorded Flow: 1,358 GPM When the results of the hydraulic calculation was compared to the available water supply curve, there was minimum safety margin of approximately 24.5 PSI. A copy of the hydraulic calculations have been attached in Appendix A. New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 4 ACCEPTANCE TESTING This system must be hydrostatically tested to 200 psi for two hours. Additionally, a main drain test and inspectors test will be conducted. The dry system shall undergo a full trip test and water shall be observed through the remote inspectors test within the required timeframe of NFPA 13 (2013 Edition). Control valve tamper switch closure tests will also be conducted. A Contractor's Certificate for Above Ground Piping will be required. MAINTENANCE TESTING A testing and maintenance program, which meets the requirements of NFPA Standard 25 shall be required to be under contract with a licensed sprinkler contractor. Test programs shall be in accordance with Table 5-1 and 12-1 of NFPA 25 and include the following: Weekly - Owner inspect to see that control valves are open, unobstructed and not leaking and all system gages are normal. Quarterly - Alarm Test, Main Drain Test Visual Inspection of Fire Department Connection Yearly - Test Backflow Assembly (DCVA) per State requirements Visually Inspect Pipe Hangers & Bracing in Accessible Spaces Conduct full Flow Test to verify water supply to sprinkler system Record static, residual and flow readings. 5 Years - Internally inspect all check valves. Daily- Building owners responsible for maintaining 40-degree temperatures (minimum) throughout all areas of each unit, including garage bays to prevent sprinkler piping from freezing. New NFPA 13 Residential Sprinkler System Design Narrative 12 South Mason Street – Building 3 – Salem, Massachusetts 06/01/2020 5 APPENDIX A HYDRAULIC CALCULATIONS