How To Find The Pitch Of A Roof With A Speed Square

Or 17 x 12 204 in.

How to find the pitch of a roof with a speed square.

The triangle shaped square was invented in 1925 by albert swanson to provide a quick accurate method for marking rafters. For example using the numbers from our roof framing square table example just above. After finding out your roof pitch angles you can use the calculator to perform the calculations for you instead of doing them manually. The pitch tells you the amount of vertical rise in inches for every 12 in.

Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. Measured rafter run rr 17 ft. 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 a magazine such as finehomebuilding is going to put out an article to teach a topic it should use the proper words and definitions.

A speed square and level can be used to easily find the pitch of a roof. It is often compared to slope but is not exactly the same. The roof pitch calculator is a convenient online tool you can use to quickly assess the pitch of your roof to determine the length of rafters you need. As a matter of fact finding the pitch of a roof was the motivating factor for how this tool was invented in the first place hence it s official name the rafter square.

I hear read all too often this misuse and usually ignore it. If we know the roof run and rafter length we find the roof slope by calculation or we use the framing square table just below and then easily find the roof rise. Finding the pitch of a roof is simple with a speed square. A roof slope of 4 12 is a 1 6 pitch a 6 12 slope is a 1 4 pitch an 8 12 slope is a 1 3 pitch and so on.

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. With a torpedo level and a speed square you can pretty accurately gauge the pitch of any roof with a gable end photo 1.