How To Estimate Roof Pitch

You ll need a level that is 12 or longer and a tape measure.

How to estimate roof pitch.

To measure the roof pitch you ll need an 18 or 24 inch level a tape measure and a pencil. Rafter rise run from the pythagorean theorem. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. As aforementioned there is no standard pitch of a roof.

One method to find the pitch is to climb on the roof and measure the rise for a 12 run. Rise run pitch where pitch is expressed in percent. You can use the following equations to find the length of the rafter and the slope. Generally roof pitch is calculated from the same formula that describes a right triangle.

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. If you do need to calculate the pitch an estimate or shortcut is usually more practical than measuring the roof s overall dimensions. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. 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.

For a simple gable roof the span wall to wall will be twice the size of the run wall to ridge horizontally. How to calculate roof pitch. How roof pitch is calculated to accurately calculate the area of your roof you must first determine its slope or pitch. Then in the attic place the end of the level against the bottom of a roof rafter and hold it perfectly level.

Divide the slope by two to get the pitch. First measure 12 inches from one end of the level and make a mark. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. It is often compared to slope but is not exactly the same.

This is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares.