How To Cut Roof Rafters With A Speed Square

I ll then rotate the square on the pivot until the 4 is lined up with the outside edge of the rafter.

How to cut roof rafters with a speed square.

Just drop your pencil into the appropriate notch and run the lip of the speed square down the edge of the board. I ll use the corner of the speed square on one edge of the 2 4 where it says pivot. 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. Move the square until the table on one side of the rectangular slot in the square is at the right pitch 5 on the top of the board.

Common rafters are the most common type of rafter in construction. To cut roof rafters start by fixing the stair gauges on your framing square to the dimensions of your pitch. Once you ve marked the lines use your pencil to draw the diagonal length on the rafter. Next set the framing square on top of the rafter beam and use a pencil to trace the outside edge of the framing square s tongue.

How to cut rafters with a rafter angle square determine the building s width and length and the rafter span in order to evaluate how many rafters are needed. Use the table marked common top cut. I ll use my speed square to measure my first cut on one end of my 2 4 rafter. This gives me an exact 4 12 cut.

The scribe bar has notches every 1 4. Swing the square until you read the desired angle on the board s edge and make your mark. Ability to read a tape measure ruler. Familiarity with using a speed square.

So say you need to trim 1 1 2 off the side of a board. Put the pivot point of the speed square a small hole marked pivot where the straight side of the square meets the side with the lip on it at the top edge of a rafter board. 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. Then determine the pitch.

I ll mark a line along the edge of the speed square. 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. You can use the speed square to mark an angle such as when cutting a rafter tail by holding the pivot point against the board. Incidentally the lipped fence on the tool allows you to use a speed square as a guide for a circular saw.