Roof Slope Requirements

Minimum slope for asphalt shingles the requirements for an asphalt shingles roof are contained in the international building code.

Roof slope requirements.

Roof pitch is the degree of building s roof slope. In cases of roof system replacement and re cover of existing low slope roof systems ibc 2018 and irc 2018 waive the codes 1 4 12 minimum slope requirement and apply a performance based positive roof drainage minimum requirement. In roof construction a roof is covered by covering materials which are supported on a structural member. The following tableprovides the minimum required allowable roof slope for each type of roofing material mentioned in the code.

Slope should be built into the structure on new buildings. The roof is the uppermost portion of the building. The basic object of the house or home is to provide shelter. The roofs can be either flat or sloping.

Amongst many decisions one has to make when designing a metal building determining metal roof minimum slope is one of them. Run in degrees and as percentage the minimum roof slope allowed by code for any type of roofis in 12 applicable only to coal tar pitch roof systems. A roof must be strong to withstand snow and wind load. Crickets should be installed behind all curbs that obstruct drainage.

Roof slope of 1 4 per foot minimum is required on all roof systems. According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. Lapped nonsoldered seam metal roofs without applied lap sealant must have a minimum roof slope of 3 12 25 slope.

The minimum roof slope for metal roof panels depend on 3 different scenarios. This means for every 12 horizontal units the roof must rise a minimum of 3 vertical units. Roof slope equivalents as rise. Match roof material and use appropriate slope match the roofing on the covered porch with the main roof.

Asphalt shingles continue to be the most widely installed roof covering option in north america. Determine the minimum slope of the roof based on the roofing material. When required for steep slope roofs section 1507 in the ibc and section r905 1 2 of the irc specify the use of an ice barrier that consists of either two layers of underlayment cemented together or a self adhering polymer modified bitumen sheet at eaves and valleys.