Minimum Allowable Slope For Shingle Roof
This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof systems in new construction.
Minimum allowable slope for shingle roof. For example if it is a very low slope water including snowmelt or. The minimum pitch for shingles is 1 6 which is equivalent to 4 inches rise to 24 inches run. Determine the minimum slope of the roof based on the roofing material. Installation on roof slopes below a 2 in 12 pitch is not recommended at all.
The minimum roof slope for metal roofs is dependent upon the roof profile. If you have a low slope roof but would love to have a shingled look rather than other solutions like rolled sheet roofing you are in. Normal roof slope for typical installation. The profile refers to the shape the metal sheets take when they bend to.
Low slope roofs present a challenge where water is concerned. The minimum slope for standing seam of roof systems shall be one quarter unit vertical in 12 units horizontal 2 percent slope. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. Why is 2 12 the minimum.
With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels. Low slope roofing shingles. If 4 12 and above is normal and 2 12 is minimum what about properties with roofs in between the two such as a 3 12 pitched roof. However those naysayers would be wrong.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. The minimum slope for an asphalt shingle roof is 2 12. For metal panel roof systems with nonsoldered seams with applied lap sealant ibc 2018 prescribes a 1 2 12 minimum roof slope. For standing seam metal roof panel systems a 1 4 12 minimum roof slope is prescribed.
The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code. Low sloped roof shingle installation. The values given here. Considering the roof slope requirement is important.
The asphalt shingle manufactures recommend that you install asphalt shingles on a recommended minimum of 4 in 12 or greater however most manufactures will warrant their shingles down to a 2 in 12 pitch if the recommended installation method is used. Asphalt shingles continue to be the most widely installed roof covering option in north america. Normal shingle installation is allowed for all roofs with a pitch of 4 12 and above. The roof pitch between 2 12 and 4 12 is considered as a low pitch roof so shingles can be installed in the roof slope between 2 12 and 4 12.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope.