To calculate the size of the roof you need to measure the size of the roof as if it were flat account for roof pitch calculate square footage and finally determine how many squares of material are required for the roof the calculator above can handle all of this simply enter the length width and pitch and it will determine the size of the roof in squares.
How to figure out square footage of a roof.
To conclude the example if your total roofing area is 17 300 square feet your waste allowance would be 17 300 x 1 1 730 square feet.
The calculator cannot account for complex shapes based on a measurement of square footage alone.
With the area measurement you can learn the approximate cost of a new roof.
Steep roofs measure your house at ground level then add in the roof s overhang for greater accuracy.
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.
Calculate square footage for a roof by measuring and by performing some basic math equations.
The total amount of roofing material you need is 17 300 1 730 19 030 square feet.
Multiply the square footage of your roof by 1 to get the 10 percent waste allowance.
1square of roofing covers 100 square feet of roof a bundle is 1 3 of a square.