Measuring Roof Pitch With Speed Square

Before miter saws and even since professional carpenters used speed squares as a quick saw guide for cutting 45 and 90 degree angles.

Measuring roof pitch with speed square.

Find a common rafter angled with the pitch of the roof. A speed square aka rafter square or triangle square is a measuring multitool. Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot. Also measure the length of half of the roof from one side of the ridge beam to the.

Finding the pitch of a roof is simple with a speed square. 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. Holding the level and speed square level locate the measurement on the speed square where it meets the bottom edge of the rafter to find the angle of the roof in degrees. The triangle shaped square was invented in 1925 by albert swanson to provide a quick accurate method for marking rafters.

This is a way of measuring the degree of steepness of the roof. 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. It is often compared to slope but is not exactly the same. Made of steel aluminum or plastic this common carpenter s tool combines a ruler a try square a protractor a line scribing tool a common width board ripping guide and a saw guide for making accurate 90 and 45 cuts with a hand or circular saw.

Mark along the outside edge of the rafter angle square for your angled cut. Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio. The number of inches that the roof rises vertically for every foot of roof. Although there s isn t any standard pitch of a roof used on all kinds of sloped roofs you can determine the range of pitches by using a roof angle calculator and by considering factors like the local climate and roofing materials.

How to use a rafter angle square for roof pitch. Photo 2 shows how to use the speed square to mark a 33 1 2 degree angle the same as you would need on a rafter tail for a roof with an 8 12 pitch. The pitch of the roof is a ratio. To calculate the size of the roof you need to measure the size of the roof as if it were flat account for roof pitch calculate square footage and finally determine how many squares of material are required for the roof the calculator above can handle all of this simply enter the length width and pitch and it will determine the size of the roof in squares.