Aluminum sheet used for roof decking or siding shall be not less than 0.032 inch (0.8 mm) in thickness.
Aluminum sheets shall be secured to the supports to adequately resist positive and negative loads. Attachments shall be at intervals not exceeding 8-inches (203 mm) o.c. and shall be secured to each other at side laps at intervals as required by rational analysis and/or tests, but shall not exceed 12-inches (305 mm) o.c.
Fasteners shall have a head, and/or be provided with washers not less than 1/2 inch (13 mm) in diameter.
Fasteners located at end laps shall be placed not more than 2 inches (51 mm) nor less than 1 inch (25 mm) from the end of overlapping sheets.