ing, using ample roofing cement between laps. Nail along all edges of roofing sheet at 4” on centers, and after nailing is completed, brush coat nail heads with roofing cement. Place nails approximately 1" edge of roofing sheets. 4, in from Fill all breaks or holes in roofing and caulk flashings as required with plastic cement, troweled on. 11-03. SHEET METAL WORK: Surfaces to which sheet metal is to be applied shall be even, smooth, sound, thoroughly clean and dry, and free from all defects that might affect the application, All cutting, fitting, drilling, and other operations in connection with sheet metal required to accomodate the work of other trades, shall be perforn- ed under this section. All accessories or other items essential to the completeness of the sheet metal installation, though not specifically shown or specified, shall also be provided under this section. All such items, except as otherwise specified, shall be non-ferrous where employed in conjunction with copper or lead, and shall be zine coated ferrous metal where employed with zinc coated iron or steel. Where sheet metal abuts or members into adjacent materials, the juncture shall be executed as indicated on the drawings or in a satisfactory manner. Flashings, gravel stops, reglets, and other sheet metal work in conjunction with roofing shall be of aluminum. All nails and other fastenings used with aluminum shall be of aluminum alloy or shall be cadmium plated. a, Materials: As furnished by the Contractor: 1. Calking Compound: Calking compound shall conform to the requirements of Federal Specification TT-C-598. 2. Aluminum: Aluminum sheet shall be of the gage or thickness called for on the drawings. Unless otherwise shown on the drawings, sheet shall be 35 alloy not less than 0.020 inches thick. 3. Nails: Nails shall conform to the requirements of Federal Specification FF-N-101 and shall be not less than 0.109 inch diameter. Nails shall be of the large head type and shall be of sufficient length to firmly secure the materials in place. Non-ferrous nails for use with aluminum shall be 56S aluminum or similar hard aluminum alloy, and for use with copper shall be hard copper or ll-2