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.
Minimum allowable slope for shingle roof.
Considering the roof slope requirement is important.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Depending on the roof profile there are minimum roof slope requirements for each panel which need to be considered.
The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
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.
The minimum slope for an asphalt shingle roof is 2 12.
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.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.
The values given here.
The minimum roof slope for metal roofs is dependent upon the roof profile.
Low sloped roof shingle installation.
Some will argue that shingles shouldn t be used for low pitch roofs at all.
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.
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 minimum pitch for shingles is 1 6 which is equivalent to 4 inches rise to 24 inches run.
To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope.
Why is 2 12 the minimum.
Low slope roofs present a challenge where water is concerned.
However those naysayers would be wrong.
Installation on roof slopes below a 2 in 12 pitch is not recommended at all.
This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof systems in new construction.
Low slope roofing shingles.
With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels.
Normal shingle installation is allowed for all roofs with a pitch of 4 12 and above.
Normal roof slope for typical installation.
The minimum slope for standing seam of roof systems shall be one quarter unit vertical in 12 units horizontal 2 percent slope.
The profile refers to the shape the metal sheets take when they bend to.