scope:

This guide specification covers the requirements for smooth surfaced bituminous built-up roofing with slopes from one in 48 to one in 2 ¼ inch to 6 inches per foot. The requirements for hot-mopped, four-ply, smooth surfaced, built-up bituminous roofing systems are included in this guide specification. For new buildings, provide a roof slope of one in 24 ½ inch per foot, minimum. On reroofing projects where the existing roof deck slopes at least one in 48 ¼ in./ft. and it is clearly impractical to provide roofing sloped at least one in 24 ½ in./ft., built-up roofing may be used.