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D. Where walls, curbs, expansion joints, etc. present an unacceptable substrate for flashing and where flashings substrates are combustible, a layer of non-combustible overlayment insulation shall be fastened to provide a suitable substrate for flashing. 3.3 APPLICATION A. General: 1. Apply roofing in accordance with roofing system manufacturer's instructions and the following requirements. Application of the roofing membrane base ply shall immediately follow application of base sheet/insulation system as a continuous operation. 2. Aesthetic Considerations: An aesthetically pleasing overall appearance of the finished roof application is a standard requirement for this project. Make necessary preparations, utilize recommended application techniques, apply the specified materials (i.e. granules, etc.), and exercise care in ensuring that the finished application is acceptable to the Owner. Excessive footprints or impressions in the surface ply will be grounds for rejection thereby requiring complete membrane tear -off and replacement. 3. Priming: a. Prime metal flanges, concrete and masonry surfaces with a uniform coating of asphalt primer. b. Primer shall provide full coverage to ensure surfaces are dark brown to black. No less than 1 to 1-1/4 gallons per square will be accepted. C. Allow primer to fully dry prior to application of asphalt/adhesive. 4. Inspect membrane and flashing application each day. Repair all deficiencies daily prior to beginning or resuming other work. a. Membrane deficiencies shall be cut open and removed as necessary. b. Repairs shall extend from lap to lap. B. Base Sheet: As a minimum the base sheet shall be mechanically attached in accordance with the base sheet fastening pattern in the contract drawings. If additional fastening is required by the manufacturer to achieve the required wind uplift resistance, the manufacturer's requirements shall be utilized. Starting at the low point of the roof, over a properly prepared substrate, apply base sheet in a shingle fashion with minimum 6" end laps and 3" side laps. Apply asphalt primer to head and plates of fasteners. C. Roof Membrane: 1. Apply membrane in accordance with the manufacturer's instructions and the following requirements. 2. Apply all layers of roofing free of wrinkles, creases or fishmouths. 3. Exert sufficient pressure by use of roller or broom on the roll during application to ensure prevention of air pockets. 4. Stagger the lap seams between the base ply layer and the finish ply layer. 5. Apply all layers of roofing perpendicular to the slope of the deck. 6. Fully bond the base ply to the prepared substrate, utilizing minimum 3 -inch side and end laps. Apply each sheet directly behind the torch applicator. Cut a dog ear angle at the end laps on overlapping selvage edges. Using a clean trowel, apply top pressure to top seal T -laps immediately following sheet application. Stagger end laps a minimum of 3 feet. 7. Fully bond the surface ply to the base ply, utilizing minimum 3 -inch side and end laps. Apply each sheet directly behind the torch applicator. Stagger end laps of the surface ply a minimum 3 feet. Cut a dog ear angle at the end laps on overlapping selvage edges. Using a clean trowel, apply top pressure to top seal T -laps immediately following sheet application. Stagger side laps of the surface IRC -1838 Indian River County Main Library Roof Replacement 07 52 16-7 Modified Bitumen Roofing (Revision 1)