The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Maximum roof pitch for shingles.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
What is the minimum pitch slope of an asphalt shingle roof.
This means for every 12 horizontal units the roof must.
Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run.
Also if asphalt shingles are installed on a roof slope of 2 12 to 4 12 it shall be provided with a double underlayment application.
Complete list of roofing types.
Run in degrees and as percentage the minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
The minimum requirement is 2 12.
Asphalt shingles do require that you have a minimum pitch to your roof.
Shingles of all types need to have a slope to function properly.
Clay and concrete tile minimum roof slope roof pitch r905 3 2.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
Roof slope equivalents as rise.
There are plenty of other options however for flat and nearly.
It is important for shingle roofs to function properly and one method of ensuring that this is achieved is to observe the pitch requirements for the shingles.
Traditional 3 tab shingles made with asphalt composite are the most popular type of shingle and are the most flexible in terms of adapting to many roof pitches.
Minimum and maximum roof slope limits vary based on specific roof system and project types.
Fortunately the requirements are quite accommodating.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
If you re having asphalt shingles put on your roof you will have to have a minimum slope.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
They won t be appropriate for all roofs.
So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run.
Manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.
Roof pitch multiplier table.
Following is a review of code requirements and nrca s roof slope guidelines as well as some additional factors designers should consider.
Degrees to pitch rise in run table.
If a roof slope exceeds this limitation the shingles should be applied by the following recommended method complying with astm d4586.
The maximum slope considered suitable for normal shingle application is 45 degrees or 12 per foot.
Secure the shingle to the roof deck with fasteners as recommended by the roofing manufacturer.
That works out to about nine degrees if that works better for you.
These shingles are appropriate for pitches as low as 4 12 pitch all the way up to a 12 12.
And 4 12 minimum roof slope for slate and wood shakes.
