How To Figure Roof Pitch With A Framing Square

How to use a framing square and its etched on tables to figure out roof slope rafter lengths.

How to figure roof pitch with a framing square.

The triangle shaped square was invented in 1925 by albert swanson to provide a quick accurate method for marking rafters. Square guides are available at most hardware and home improvement centers. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. This article explains how to make quick use of a framing square and its imprinted data to get some basic roof measurement data like roof pitch or slope rafter lengths and end cuts.

A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. Fix stair gauges on the framing square to mark the pitch. How to find roof slope rafter length on a framing square how would we use our framing square to measure or to calculate the slope and rafter lengths of this historic herefordshire u k.

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. How roof pitch is calculated. Find the unit rise say inches per foot of the roof on the top line in the framing square rafter table e g.

A carpenter s framing square includes some tables stamped right into the tool itself. It is often compared to slope but is not exactly the same. 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. A 6 inch rise per foot.