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.
Minimum roof slope for cedar shingles.
The minimum roof pitch for shingles and shakes is 14 degrees.
Page 23 cedar care maintenance overview a word about topical treatments for installed roofs topical treatment products power washing the beauty of cedar download pdf page 24 coverage and exposure tables shingle coverage table 1 shingle exposure table 2 shake coverage table 3 shake exposure table 4 download pdf.
Over the membrane install vertical 2x4 battens lined up with the rafters then spaced sheathing as described below.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
Minimum required slope x in 12 minimum required slope degrees asphalt shingles.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
To achieve a sound watertight roof the gauge of the shingle assuming the standard 5x or 400mm shingle must be closed to 95mm giving a 4 ply roof.
Wood shingles are more susceptible to leaks than composite or asphalt shingles because they don t lock as tightly or lay as flat as traditional shingles.
What is the minimum pitch slope of an asphalt shingle roof.
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.
Asphalt shingles can only be installed on roof slopes of 2 12 or greater.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
Asphalt shingles minimum roof slope roof pitch r905 2 2.
The minimum recommended slope for standard installation of shingles is 3 12 and 4 12 for shakes.
At these pitches there is a possibility of some water penetration.
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.
That works out to about nine degrees if that works better for you.
Roofing material or system.
The minimum requirement is 2 12.
On lower slopes shingles or shakes may be installed over a fully waterproof built up roof bur or membrane roof.
Minimum pitch for cedar roofs if you desire a cedar roof for your home the ideal pitch for your roof ranges from a five pitch to a 12 pitch.
Shingles of all types need to have a slope to function properly.
While a low pitch roof may not show the aesthetic qualities of cedar shingles to full advantage they provide a lightweight durable solution where a pitched roof is required.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.