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2.5 FABRICATION <br />A. General: Fabricate roll -formed sheet metal roofing panels with UL -certified, portable roll -forming <br />equipment capable of producing roofing panels for sheet metal roofing assemblies that comply with <br />UL 580 for wind -uplift resistance classification specified in "Quality Assurance" Article. Fabricate roll - <br />formed sheet metal according to equipment manufacturer's written instructions and to comply with details <br />shown. <br />B. Fabrication Tolerances: Fabricate sheet metal roofing that is capable of installation to a tolerance of 1/4 <br />inch in 20 feet (6 mm in 6 m) on slope and location lines as indicated and within 1/8 -inch (3 -mm) offset <br />of adjoining faces and of alignment of matching profiles. <br />C. Form exposed sheet metal work to fit substrates without excessive oil canning, buckling, and tool marks; <br />true to line and levels indicated; and with exposed edges folded back to form hems. <br />1. Lay out sheet metal roofing so transverse seams, if required, are made in direction of flow with <br />higher panels overlapping lower panels. <br />2. Offset transverse seams from each other 12 inches (300 mm) minimum. <br />3. Fold and cleat eaves and transverse seams in the shop. <br />4. Form and fabricate sheets, seams, strips, cleats, valleys, ridges, edge treatments, integral flashings, <br />and other components of metal roofing to profiles, patterns, and drainage arrangements shown on <br />Drawings and as required for leakproof construction. <br />D. Expansion Provisions: Fabricate sheet metal roofing to allow for expansion in running work sufficient to <br />prevent leakage, damage, and deterioration of the Work. Where lapped expansion provisions cannot be <br />used, form expansion joints of intermeshing hooked flanges, not less than 1 inch (25 mm) deep, filled <br />with butyl sealant concealed within joints. <br />E. Sealant Joints: Where movable, nonexpansion-type joints are indicated or required to produce <br />weathertight seams, form metal to provide for proper installation of elastomeric sealant in compliance <br />with SMACNA standards. <br />F. Metal Protection: Where dissimilar metals will contact each other, protect against galvanic action by <br />painting contact surfaces with bituminous coating, by applying self -adhering sheet underlayment to each <br />contact surface, or by other permanent separation as recommended by fabricator of sheet metal roofing or <br />manufacturers of the metals in contact. <br />G. Sheet Metal Accessories: Custom fabricate flashings and trim to comply with recommendations in <br />SMACNA's "Architectural Sheet Metal Manual" that apply to design, dimensions, metal, and other <br />characteristics of item indicated. Obtain field measurements for accurate fit before shop fabrication. <br />1. Form exposed sheet metal accessories without excessive oil canning, buckling, and tool marks and <br />true to line and levels indicated, with exposed edges folded back to form hems. <br />2. Seams: Fabricate nonmoving seams with flat -lock seams. Form seams and seal with elastomeric <br />sealant unless otherwise recommended by sealant manufacturer for intended use. Rivet joints <br />where necessary for strength. <br />3. Sealed Joints: Form nonexpansion but movable joints in metal to accommodate elastomeric <br />sealant. <br />4. Conceal fasteners and expansion provisions where possible. Exposed fasteners are not allowed on <br />faces of accessories exposed to view. <br />5. Fabricate cleats and attachment devices of sizes as recommended by SMACNA's "Architectural <br />Sheet Metal Manual" for application, but not less than thickness of metal being secured. <br />H. Do not use graphite pencils to mark metal surfaces. <br />Wabasso Beach Park 07610-6 <br />Indian River County <br />DAA Project No. 6008 <br />