26 September 2006
structural design. Further, with an occupied building, construction noises, fumes, fire
hazards, and roof access all take on increased importance.
The two main types of roof systems are steep slope and low slope.
Steep slope roofing systems are water-shedding types of roof coverings installed on
slopes greater than 3:12 (14 degrees) and typically consist of asphalt shingles, slate,
tile, and metal roofing.
Low slope roofing systems are weatherproof membrane types of roof systems installed
on slopes at or less than 3:12 (14degrees). Types of low sloped roofing systems
include bituminous built-up (BUR), modified bitumen (MB) roofing, single-ply (i.e., PVC,
EPDM), sprayed-in-place polyurethane foam (SPF), and standing seam metal roofing