How To Work Out The Pitch Of A New Roof

For a roof with the ridge above one wall the span is the same as the run.

How to work out the pitch of a new roof.

Express roof pitch as the ratio of the amount of the vertical rise of a roof or rise over the corresponding horizontal distance or run you write the pitch assuming a run of 12 inches thus the ratio would describe how much a roof rises for each foot of the run. Pitch is the incline of the roof represented as the ratio of rise to the span twice the run. To convert between american roofing ratios and pitch degrees follow these steps. A 12 12 pitch roof has a pitch angle of 45.

You ll need a level that is 12 or longer and a tape measure. On the roof hold the level perfectly level and measure the height from the roof to the level 12 inches away from where the level touches the surface this will be the rise. This free roof pitch calculator will take your roof width see the picture and rise the height of the roof and will calculate the roof pitch both as numeric value. Find the inverse tangent of the pitch to find the angle in degrees.

Here are a couple examples. One method to find the pitch is to climb on the roof and measure the rise for a 12 run. As aforementioned there is no standard pitch of a roof. Divide the slope by two to get the pitch.

Here is the equation in full roof pitch 1 tangent rise run. If your roof pitch is greater than 3 your roof is considered pitched read more about roof pitch at wikipedia. Divide the first part of the ratio by 12 to work out the pitch. For example if the roof rises 4 feet and the span is 16 feet twice the run then the pitch is 4 16 or 1 4.

The roof pitch measures the steepness of your shed roof and typically takes values from 1 to 12. For a simple gable roof the span wall to wall will be twice the size of the run wall to ridge horizontally. Once you have these two measurements you ll need to grab hold of a calculator and divide the rise by the run to work out the tangent.