There are several areas of decking that are suspected of deterioration, remediation for these areas is as follows: Workers engaged in the re-roofing/decking remediation must comply with OSHA regulations. Open existing TPO membrane. Remove deteriorated decking and dispose of all debris. Install new CDX plywood sheeting – match existing thickness -fastened to existing roof trusses, at the seam ends of plywood – install new 2”x6” framing to support the seams, fasten entire perimeter of plywood 6” o.c. with the appropriate fasteners. Infill affected areas with insulation to match existing. For the remaining roof area, slit existing membrane in a 10’ x 10’ grid. Overlay existing membrane with two layers of 2.6” Polyisocyanurate insulation (R=30). Stagger joints 12” in all directions from the preceding layer. Mechanically fasten per manufacturer’s fastening pattern to comply with warranty. Provide new 2”x6” wood blocking and plywood strips at perimeter edges to be the same thickness as new insulation, installed per NRCA details. Install a new mechanically fastened .060 TPO roofing system, complete with all necessary flashings and caulking where needed per manufacturer’s instructions. At perimeter, wrap new TPO membrane over and down the exterior face of the new wood blocking. Furnish and install .040 commercial roof lap-style aluminum gutters: 6” wide with 4” x 5” downspouts per SMACNA standards.
