How To Estimate Roof Pitch

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.

How to estimate roof pitch.

You ll need a level that is 12 or longer and a tape measure. Here are a couple examples. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. 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.

If you do need to calculate the pitch an estimate or shortcut is usually more practical than measuring the roof s overall dimensions. One method to find the pitch is to climb on the roof and measure the rise for a 12 run. Generally roof pitch is calculated from the same formula that describes a right triangle. 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.

As aforementioned there is no standard pitch of a roof. How to calculate roof pitch. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. 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.

Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. It is often compared to slope but is not exactly the same. Divide the slope by two to get the pitch. Rafter rise run from the pythagorean theorem.

Then in the attic place the end of the level against the bottom of a roof rafter and hold it perfectly level. This is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares. Rise run pitch where pitch is expressed in percent. For a simple gable roof the span wall to wall will be twice the size of the run wall to ridge horizontally.

First measure 12 inches from one end of the level and make a mark.