Ibc Roof Slope Requirements

3 12 minimum roof slope for metal roof panels with nonsoldered seams without applied lap sealant metal shingles and wood shingles.

Ibc roof slope requirements.

1507 2 3 underlayment underlayment shall comply with section 1507 1 1. 2 1 2 12 minimum roof slope for clay and concrete tile. For roof slopes from two units vertical in 12 units horizontal 17 percent slope up to four units vertical in 12 units horizontal 33 percent slope double underlayment application is required in accordance with section 1507 2 8. Lapped nonsoldered seam metal roofs with applied lap sealant must have a minimum roof slope of 1 2 12 4 slope.

Lapped nonsoldered seam metal roofs without applied lap sealant must have a minimum roof slope of 3 12 25 slope. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. For roof slopes from two units vertical in 12 units horizontal 17 percent slope up to four units vertical in 12 units horizontal 33 percent slope double underlayment application is required in accordance with section 1507 2 8. Minimum roof slope roof pitch r905 10 2 1.

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. What kind of rain fall rates are you looking at. The ibc minimum required roof slope is 1 4 in 12 which is about 1 2 degrees for a membrane roof. Asphalt shingles shall only be used on roof slopes of two units vertical in 12 units horizontal 17 percent slope or greater.

Where the roof slope exceeds 21 units vertical in 12 units horizontal 21 12 shingles shall be installed as required by the manufacturer. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures. If you are using a metal panel roof then you may need to go steeper. For steep slope roof systems ibc 2018 provides for a 1 12 minimum roof slope for mineral surfaced roof roll roofing.

Amongst many decisions one has to make when designing a metal building determining metal roof minimum slope is one of them. 2 12 minimum roof slope for asphalt shingles photovoltaic pv shingles and building integrated pv. Roof pitch is the degree of building s roof slope. Minimum roof pitch for metal building.

And 4 12 minimum roof slope for slate and wood shakes. Reroofing shall not be required to meet the minimum design slope requirement of one quarter unit vertical in 12 units horizontal 2 percent slope in section 1507 of the international building code for roofs that provide positive roof drainage.