Ibc Roof Slope Requirements
1507 2 3 underlayment underlayment shall comply with section 1507 1 1.
Ibc roof slope requirements. The code may still have a provision for hot mopped asphalt but i cannot see this being used in the middle east. Amongst many decisions one has to make when designing a metal building determining metal roof minimum slope is one of them. 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. 2 12 minimum roof slope for asphalt shingles photovoltaic pv shingles and building integrated pv.
If you are using a metal panel roof then you may need to go steeper. What kind of rain fall rates are you looking at. Asphalt shingles shall only be used on roof slopes of two units vertical in 12 units horizontal 17 percent slope or greater. Lapped nonsoldered seam metal roofs without applied lap sealant must have a minimum roof slope of 3 12 25 slope.
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. It determines how many inches the roof should rise for every 12 inches expanding on the horizontal side. Minimum roof pitch for metal building.
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. And 4 12 minimum roof slope for slate and wood shakes. 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. 3 12 minimum roof slope for metal roof panels with nonsoldered seams without applied lap sealant metal shingles and wood shingles.
The ibc minimum required roof slope is 1 4 in 12 which is about 1 2 degrees for a membrane roof. 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. Roof pitch is the degree of building s roof slope. 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 code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. Lapped nonsoldered seam metal roofs with applied lap sealant must have a minimum roof slope of 1 2 12 4 slope.