1507.3.3.2 High-slope roofs.
BC § 1507.3.3.2
For roof slopes of four units vertical in 12 units horizontal (33-percent slope) or greater, underlayment shall be a minimum of one layer of underlayment felt applied shingle fashion, parallel to, and starting from the eaves and lapped 2 inches (50.8 mm), fastened only as necessary to hold in place.













