How To Estimate Roof Pitch

Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs.

How to estimate roof pitch.

For a simple gable roof the span wall to wall will be twice the size of the run wall to ridge horizontally. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. One method to find the pitch is to climb on the roof and measure the rise for a 12 run. Then in the attic place the end of the level against the bottom of a roof rafter and hold it perfectly level.

It is often compared to slope but is not exactly the same. Roof pitch calculator results explained slope the slope of a roof is represented as x 12 where x is the number of inches in rise for every 12 inches of run. Here are a couple examples. As aforementioned there is no standard pitch of a roof.

Generally roof pitch is calculated from the same formula that describes a right triangle. Divide the slope by two to get the pitch. Rise run pitch where pitch is expressed in percent. Rafter rise run from the pythagorean theorem.

You can use the following equations to find the length of the rafter and the slope. You ll need a level that is 12 or longer and a tape measure. How to calculate roof pitch. If you do need to calculate the pitch an estimate or shortcut is usually more practical than measuring the roof s overall dimensions.

In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. 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. To measure the roof pitch you ll need an 18 or 24 inch level a tape measure and a pencil. 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.

Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run.