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.
At these low pitches 14 22 degrees care must be taken and a water impermeable vapour permeable underlay must be used underneath with a ventilated space between the membrane and the shingles.
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.
Roofing material or system.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
What is the minimum pitch slope of an asphalt shingle 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.
On lower slopes shingles or shakes may be installed over a fully waterproof built up roof bur or membrane roof.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
Minimum required roof slope for roofing materials.
9 46 built up roof asphalt.
Asphalt shingles minimum roof slope roof pitch r905 2 2.
The minimum roof pitch for shingles and shakes is 14 degrees.
In 12 0 25 in 12 1 19 built up roof coal tar pitch.
Minimum required slope x in 12 minimum required slope degrees asphalt shingles.
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.
That works out to about nine degrees if that works better for you.
Over the membrane install vertical 2x4 battens lined up with the rafters then spaced sheathing as described below.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
The minimum requirement is 2 12.
This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.
At these pitches there is a possibility of some water penetration.
18 43 asphalt shingles with special underlayment requirements 2 in 12.
Asphalt shingles can only be installed on roof slopes of 2 12 or greater.
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.