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♦r ALTERNATE MATERIALS AND/OR METHODS APPLICATION REASON FOR PROPOSED ALTERNATIVE: The request involves two separate fire walls of the new pre-engineered steel building which are adjacent to existing buildings. In both cases, the firewalls will be supported only by the new building, with existing buildings providing no support to the firewalls. Existing buildings are of Type II-B construction and are U-1 AG-Exempt structures. The proposed building is pre-engineered steel but contains wood framing, thus is considered to be of Type V-B construction. Occupancy is primarily F-1 (Food Processing)with a small area of B (Office)occupancy. The proposed building will be fire sprinklered in accordance with NFPA 13. Firewall rating for an F-1 occupancy is 3 hours, while both U and B occupancies allow 2-hour rating (OSSC Table 706.4, including Exception A). In addition, Section 706.2 requires that a firewall allow collapse of structure on either side. With the new building of Pre-Engineered Steel Construction (PEMB), meeting full code compliance is not practical. Therefore, we are requesting that we be allowed to reduce fire rating of the firewall by the use of additional fire sprinkler coverage. North Wall: • This wall is solid grouted 80" CMU, meeting the required 3-hour rating. Additional fire sprinklers are proposed to reduce fire protection of the wall support (spandrel) beam to 2-hour protection and the building end wall roof beam and columns to be unprotected or at a minimum that these are allowed to be of 2- hour protection. East Wall: This wall is proposed to be a 2-hour rated assembly using typical PEMB construction with 2-layers of Type X GWB each face. No protection is proposed for building columns. Fire sprinkler coverage at"double density" is proposed to be added to both interior and exterior faces of the 2-hour wall.