How To Figure Out Roof Pitch With Speed Square

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How to figure out roof pitch with speed square.

A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. Find the inverse tangent of the pitch to find the angle in degrees. Check your results with the omni roof pitch calculator. 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.

A speed square and level can be used to easily find the pitch of a roof. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. The triangle shaped square was invented in 1925 by albert swanson to provide a quick accurate method for marking rafters. To accurately calculate the area of your roof you must first determine its slope or pitch.

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. Because of its compact size it is frequently used as a saw guide when cutting framing members as well as a layout tool for quick 45 and 90 degree cuts. Read the pitch on the side of the rafter square. Leah answers a viewer s question about how to calculate the pitch of a roof on a structure.

Set the level on the edge of the speed square as shown below then place the heel of the speed square on a rafter or gable edge of the roof. Divide the first part of the ratio by 12 to work out the pitch. Marvel at your mathematical. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run.

A 12 12 pitch roof has a pitch angle of 45. Place the pivot point against the shingles. Then place a torpedo level on the fat base of the rafter square and adjust the square until the level is level. As aforementioned there is no standard pitch of a roof.

To convert between american roofing ratios and pitch degrees follow these steps.