Shingles of all types need to have a slope to function properly.
Maximum roof pitch for asphalt shingles.
But shingle roofing is not watertight in the sense that standing water or wind driven water on a low slope roof can work its way up between the laps which is the reason for the minimum 2 12 slope.
All asphalt shingle roofs with a pitch of 4 12 or more have an underlayment of 15 lb.
18 43 asphalt shingles with special underlayment requirements 2 in 12.
In 12 0 25 in 12 1 19 built up roof coal tar pitch.
Wood and slate shingles do not lock together as tightly as other types of shingles.
Nrca s recommended minimum roof slope guidelines for steep slope roof systems generally are greater at steeper inclines than those in the building code.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
9 46 built up roof asphalt.
Asphalt felt paper that is tacked to the roof sheathing.
If you re having asphalt shingles put on your roof you will have to have a minimum slope.
Roofing material or system.
Pitched roofs are most often associated with asphalt shingles although standing seam roofs are becoming ever more popular on pitched roofs as well.
5 12 to 12 12 pitch.
They won t be appropriate for all roofs.
The maximum slope considered suitable for normal shingle application is 45 degrees or 12 per foot.
Fortunately the requirements are quite accommodating.
Considering the roof slope requirement is important.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
For example if it is a very low slope water including snowmelt or.
Minimum required slope x in 12 minimum required slope degrees asphalt shingles.
The minimum slope for an asphalt shingle roof is 2 12.
Wood and slate shingles are used in many of the same types of roofs as asphalt composite shingles but may not be appropriate for roofs near the lower end since they are more susceptible to leaking.
That works out to about nine degrees if that works better for you.
For asphalt shingle clay and concrete tile metal shingle slate and wood shake and shingle roof systems nrca recommends slopes of 4 12 or more.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
Why is 2 12 the minimum.
The minimum requirement is 2 12.
Shingles can be fabricated from a wide range of materials such as asphalt least expensive to natural wood metal tiles and heavy slate most expensive.
If a roof slope exceeds this limitation the shingles should be applied by the following recommended method complying with astm d4586.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
What is the minimum pitch slope of an asphalt shingle roof.
Secure the shingle to the roof deck with fasteners as recommended by the roofing manufacturer.
Minimum required roof slope for roofing materials.
