How To Cut Roof Rafters With A Speed Square

Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.

How to cut roof rafters with a speed square.

The rafter square or speed square does more than mark perpendicular lines. Before miter saws and even since professional carpenters used speed squares as a quick saw guide for cutting 45 and 90 degree angles. The roof rafters provide integral structural support to the roof. Building plans will specify the slope a roof should have.

The rafter square makes it easier to cut the correct angles for anyone looking to make custom roof trusses. This is the first episode of a series that i am making called construction rocks this series will help teach skills useful when building a house. Demonstrate the basics on calculating laying out and cutting a common rafter for either a full gable roof or for a shed roof on a porch or small addition. The key to accurately cutting the necessary angles is the proper use of a basic carpentry tool the framing square.

The secret to making a good rafter is cutting the proper angle. Locate the desired roof pitch on the common top cuts table of. In this first installment we ll start with roof framing. A bevel square can also be set to the plumb cut angle and used to mark the rafter s top overhang and bird s mouth cuts.

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. Familiarity with using a speed square. 2 lay out a plumb cut on a rafter. Ability to read a tape measure ruler.

Today we are tackling a big beginner lesson which is common rafter layout and cutting.