Take your area result and multiply it by the pitch multiplier or slope correction factor found in the table above to arrive at the roof s surface area.
Roof multiplier for pitch.
For roof slopes expressed as x in 12 rise in run the roof pitch multiplier is determined by finding the square root of rise run 1.
Calculate the slope of the roof.
The maths behind this number is that it is the square root of rise run 2 1.
And for a roof with a slope of 6 12 that number 1 118 is your roof slope multiplier.
One method to find the pitch is to climb on the roof and measure the rise for a 12.
For this example let s assume your roof covers an area that is 20 feet wide and.
Step 1 multiply 20 and 40 which equals 800.
You might like to use this roof slope calculator.
Another method to find the roof pitch is to go into the attic and measure the rise.
Roof is 6 12 pitch and measures at 2 400 square feet so 2400 x 1 12 2 688 2 88 sqs added for pitch.
Measure from the attic.
If the home measures 20 x 40 and has a 7 12 roof then to calculate the slope of the roof follow these steps.
A roof pitch multiplier also known as a roof pitch factor is a number that when multiplied by the area covered by a sloped roof gives the actual area of the roof.
Take the area of the roof s footprint say it s 5 000 square feet and multiply 5 000 by 1 118.
Enter your numbers into this go to roof pitch calculator.
A roof pitch multiplier also called a roof pitch factor is a number that is multiplied by the area covered by a sloped roof to produce the area of the actual surface of the roof.
Measure from the roof.
2280 1900 380 feet added for pitch.
Now you re ready to price out the materials.
How to calculate the pitch of a roof method one.
That gives you 5 590 square feet which is the actual area of the surface of the roof.
Get your roof size by using this roof pitch calculator.
Step 2 find the value of 7 12 from the roof slope multiplier table which is 1 16.