How Do I Figure Out Roof Pitch

For a simple gable roof the span wall to wall will be twice the size of the run wall to ridge horizontally.

How do i figure out roof pitch. How to calculate roof pitch. Take a measurement of 12 inches using a level. Position your level against the roof until the bubble of the vial sits between two lines. See the image below for more explanation on rise run and pitch.

Rafter rise run from the pythagorean theorem. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. The slope is the same as the pitch. Rise run pitch where pitch is expressed in percent.

One method to find the pitch is to climb on the roof and measure the rise for a 12 run. Take the measurement of the vertical. How to measure roof pitch to measure the roof pitch you ll need an 18 or 24 inch level a tape measure and a pencil. Pitch tan angle where angle is the roof pitch expressed in degrees.

First measure 12 inches from one end of the level and make a mark. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. For more complex roofs you may need to calculate it section by. A 12 in 12 pitch is a steep 45 degree angle roof.

For a roof with the ridge above one wall the span is the same as the run. Pitch is the incline of the roof represented as the ratio of rise to the span twice the run. 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.

Before taking any measurements you must first confirm that it s safe to walk on your roof.