Divide your roof pitch by 12.
How do you find the area of a roof.
And that s the number you were looking for.
8 inches and you have an 8 in 12 pitch.
Now you re ready to price out the materials.
Next square your result.
The answer is the number of roofing squares for the roof.
In cases where a roof has a complex shape such as in the image to the right measuring the dimensions and areas of each part of the roof to calculate total area will result in a more accurate measurement of area.
Calculating the area true once you have your roof s pitch divide the number by 12.
Both metric and imperial measurement systems are displayed in a popup menu over the results area.
The calculated area is only an estimation.
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.
Convert the area to roofing squares.
If this distance measures 4 inches you have a 4 in 12 pitch.
Calculating an area of a triangle when estimating a roof.
This distance is the rise.
Pitch measurement method 1.
For example if your measurement is seven inches the rise is expressed as 7 12 in roofing terminology.
The length l times the height h of a triangle is twice its area a2.
This applies to lengths as well as areas.
1 roof square 100 square feet.
If your number is 1 3 squared would yield 1 9 after that add 1 to your number.
For example if your roof s pitch is 4 in 12 you would divide 4 by 12.
Calculate the square footage of a gambrel style roof using imperial measurements.
1 9 1.
Measure the distance from the surface of the roof to the bottom of the level at the 12 inch mark.
The lower slope length is measured from outside wall to the start of the upper sloped roof section.
Roof pitch is given as the number of inches in height change over the distance of one foot.
That gives you 5 590 square feet which is the actual area of the surface of the roof.
On a ladder beside the roof place the level a foot or so up the roof hold it level and measure from the 12 inch mark on the level s bottom straight down to the roof.
Because each 100 square feet of roof is one roofing square divide the total area from step 1 by 100.