How To Use A Roof Rafter Square

This simple device is crammed with tables data and tricks that allow a carpenter to lay out roof rafters stairs or other building features.

How to use a roof rafter square. First determine the width of the building the rafter span and the length for the number of rafters that will be needed. Place a 2 by 6 board on sawhorses to lay out the first full length or common rafter. Place the square with its fence on the top edge of the lumber. Locate the desired angle on the hypotenuse side of the square and pivot the tool until that angle s notch lines up with the top edge.

For a 24 foot wide building the run would be 12. Then divide the span by two to get the rafter run the length each rafter must cover. Read the pitch on the side of the rafter square. With a torpedo level and a speed square you can pretty accurately gauge the pitch of any roof with a gable end photo 1.

The pitch is defined as the vertical distance a roof. How to use a framing square. Then place a torpedo level on the fat base of the rafter square and adjust the square until the level is level. You can use a speed square to find pitches.

For example if your roof is a twelve over twelve that is it has a rather steep forty five degree pitch then the unit length of the rafter is to be found on the face of the square below the. Determine the slope or pitch of the roof by referring to your building plans. 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. Ensure that the wood surfaces are well planed and sturdily attach to one another before you begin.

How to build roof rafters using a framing square. Simply move the pivot point against the edge of your board lining up the edge of the board with your desired angle. Choose or determine a pitch the angle at which the rafters rise. To look at the face of the rafter square hold the body with your left hand with the tongue pointing to your right.