Asphalt shingles can only be installed on roof slopes of 2 12 or greater.
Minimum roof pitch for asphalt shingles on flat roof.
They won t be appropriate for all roofs.
So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run.
Let owens corning help you determine when it is time for a new roof and then let us help you choose the shingles for your roof that are right for you.
For example if it is a very low slope water including snowmelt or rainwater drains slowly and this increases the chances of.
We can even help you find a professional to install it.
Asphalt shingles do require that you have a minimum pitch to your roof.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
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.
Fortunately the requirements are quite accommodating.
For those who don t understand the roof pitch number here is a way to envision it.
The minimum requirement is 2 12.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
Why is 2 12 the minimum.
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.
Manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.
Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
That works out to about nine degrees if that works better for you.
Roof pitch multiplier table.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Asphalt shingles minimum roof slope roof pitch r905 2 2.
Considering the roof slope requirement is important.
This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
Owens corning produces high quality asphalt coating asphalt sealants and adhesives for asphalt shingles.
Degrees to pitch rise in run table.
Asphalt composition shingles are designed to be installed on roof slopes greater than a 4 in 12 pitch.
Therefore the asphalt manufactures base their warranties around the minimum recommended pitch of 4 in 12.
What is the minimum pitch slope of an asphalt shingle roof.
Experience the total owens corning roofing system and high quality roofing shingles.
Minimum roof pitch for shingles 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.
Roof slope equivalents as rise.
