To use this handy roofing calculator you will need to divide the roof plans into separate square/rectangle areas. Once this is complete you will need to enter the roof pitch. The roof pitch is measured by dividing the horizontal run by the vertical rise. An easy way to measure the roof pitch (on an existing roof) is to download an app on your phone called Pitch Guage. This allows you to rest your phone on the roof and it will show you the degrees pitch.
You will then enter the “total length around eaves” which is basically the total lineal metres around the outer bottom edge. Next enter the total lineal metres of the hips. Hips are the diagonal lines measuring from the corner of the roof. Finally, enter the total length of the horizontal ridge.
The roofing calculator will calculate the roofing materials required to complete your asphalt shingle roof.