How To Work Out The Slope Of A Roof

Square root width x width height x height slope length.

How to work out the slope of a roof.

The standard pitch of most residential roofs ranges between 4 in 12 and 9 in 12. This theorem is done by multiplying the square s square root by the sum of the squared width and the squared height. Access one of the rafters then take the measurement this way. Locate the level s 12 inch mark.

Formula for calculating the slope the length of a slope is calculated using the pythagorean theorem. Calculate the roof pitch as the proportion of rise and run. For example if your roof rises 7 inches for every 12 inches of horizontal run then your roof has a 7 in 12 pitch. The horizontal distance in the ratio will be 12 while the vertical distance is the measurement you took from the rafters.

Recalculate this value into an angle. Angle arctan pitch arctan 0 25 14. To do this you will need to write down the measurements that you have taken from the rafters. Pitch rise run 1 5 6 25.

The slope of your roof is the ratio of the vertical distance or rise of the roof to the horizontal distance or run. Use a level against the underside of the rafter you re measuring to get the most accurate value. Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m.