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CARLSON Rgs, ,...� EIT Revised d AugAu 22, 2024 J U N G E ARCHITECTS PC Marion County ARCHITECTURE • INTERIOR DESIGN Public Work Department 5155 Silverton Rd NE Salem, OR 97305 RE: AM&M for Fire Sprinkler Coverage at Entry Canopy K&E Excavating Office Remodel 3871 Langley St SE, Salem OR At the above referenced project,we are requesting the approval of an alternate materials and method for the fire sprinkler coverage for the exterior entry canopy area. The reason for this request is due to the difficulty to install and long term dependency on an anti-freeze protected automatic fire suppression system into the designed canopy structure. PROJECT BACKGROUND INFORMATION: Overall Construction Assemblies: • The main building system is a PEMB 2-story shell with a wood framed second floor system. • We have classified the building as Type V-B construction. • The occupancy classification is B with a small portion of S-1. • The existing remodeled building project will extend the existing fire suppression system to cover all indoor spaces. • The exterior canopy is constructed with glulam beam trusses and rafter supporting a 2x6 T&G decking w/plywood shear panels on top. It will have a Class-A metal roof system.The canopy is supported by tube steel posts and a 2x6 wood framed bearing wall along the face of the PEMB building system.The 2x6 wall is clad with brick veneer&cement fiber lap siding. Challenges for installing fire sprinklers: • The exterior canopy is unheated and therefore would require a"dry"or"anti-freeze" system. • The only way to install sprinklers would be to run piping on top of the 2x6 decking and conceal this with additional framing.The sprinkler heads would pop down through the roof structure. Down heads are not allowed in a "dry"system and while permitted by NFPA the "anti-freeze"system would have standing water in those down heads which has been known to have a long term functionality problems. • Sidewall heads must be installed within 3"of the roof plan but cannot be used due to the slope of the roof plane which will interrupt the flow of water and prevent it from covering the area. Furthermore, the depth from the wall is greater than the sidewall head will cover, thus requiring some additional down heads. PROPOSED ALTERNATE SOLUTION: Construct exterior canopy with non-combustible coiumns and Heavy Timber roof construction per OSSC 602.4.4 Type IV-HT and omit the fire sprinkler system from this area. See attached plan area. APPROVAL REQUIEMENTS: DESCRIBE WHY, HOW, ETC., THE PROPOSED ALTERNATE IS EQUIVALENT AND MEETS THE INTENT OF THE CODE IN TERMS OF"STRENGTH, EFFECTIVENESS, FIRE RESISTANCE, DURABILITY, HEALTH, AND SAFETY": Page 1 of 5 3095 RIVER ROAD NORTH • SALEM,OREGON 97303 • 503-390-0281 • FAX 503-390-2459