Asphalt shingles continue to be the most widely installed roof covering option in north america.
Minimum roof pitch in michigan.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
Importance of a roof pitch.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Roof slope multipliers for roof components of sloping roofs multiply by the figures given below to obtain the cost per square foot of horizontal projection.
Fasteners for asphalt shingles shall be galvanized stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 2 67 mm shank with a minimum 3 8 inch diameter 9 5 mm head of a length to penetrate through the roofing materials and a minimum of 3 4 inch 19 1 mm into the roof sheathing.
The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions.
Where the roof sheathing is less than 3 4 inch 19 1 mm thick the nails.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
In general determining the pitch of an existing roof is a simple calculation.
Fasteners for asphalt shingles shall be galvanized steel stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 3 mm shank with a minimum 3 8 inch diameter 9 5 mm head complying with astm f1667 of a length to penetrate through the roofing materials and not less than 3 4 inch 19 1 mm into the roof sheathing.
So you would need to pick the right option as most regular standing seam metal roofs will require a roof pitch of 2 12 or even 3 12 at a minimum.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
That works out to about nine degrees if that works better for you.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
For example a roof with a 6 inch 12 pitch is one where it rises 6 inches vertically for every 12 inches of the horizontal run.
The chief reason for having a roof pitch is to redirect water and snow away from the roof and avoid any percolation that might result from stagnation of water on the roof.
You could also opt for a pvc flat roofing membrane.
There are some standing seam metal roofing options available from atas and other manufacturers that can be installed on a roof with pitch of 1 12.
This can be accomplished by measuring the number of inches the roof rises vertically for every 12 inches it extends horizontally.
Shingles of all types need to have a slope to function properly.
What is the minimum pitch slope of an asphalt shingle roof.
Rise multiplier rise multiplier 1 to 12 1 01 6 to 12 1 12 2 to 12 1 01 8 to 12 1 20 3 to 12 1 03 12 to 12 1 42 4 to 12 1 06 15 to 12 1 60 5 to 12 1 08 18 to 12 1 80.
