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.

How to work out the slope of a roof.

Formula for calculating the slope the length of a slope is calculated using the pythagorean theorem. The slope of your roof is the ratio of the vertical distance or rise of the roof to the horizontal distance or run. Access one of the rafters then take the measurement this way. Recalculate this value into an angle.

Square root width x width height x height slope length. The horizontal distance in the ratio will be 12 while the vertical distance is the measurement you took from the rafters. This theorem is done by multiplying the square s square root by the sum of the squared width and the squared height. Pitch rise run 1 5 6 25.

Use a level against the underside of the rafter you re measuring to get the most accurate value. Locate the level s 12 inch mark. Calculating roof slope is done by calculating the number of inches your roof slope rises vertically for every 12 inches it extends horizontally. To do this you will need to write down the measurements that you have taken from the rafters.

Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m. Calculate the roof pitch as the proportion of rise and run. Finally you can find the roof pitch in the form of x 12.