How To Cut Roof Angles

This video will show you how to figure length and cut a common rafter for a gable roof using a framing square.

How to cut roof angles.

The number of rafters needed will be determined by the length of your roof. All roof rafters should be identical so follow the same steps to measure the plumb cut tail cut and birdsmouth cut. The combination of two numbers are used to display or show the roof pitch. Roof pitch refers to the amount of rise a roof has compared to the horizontal measurement of the roof called the run.

W ll factor horizontal inches to add from short point to long point of the cut angle from the bottom to the top of the sheathing. W x cosine horizontal inches to add from short point to long point of the cut angle from the bottom to the top of the. Angle the angle of a roof is the same as the roof s slope except instead of being represented as x 12 it is represented in degrees. To see how pitch impacts the look of a garage and changes cost click the design center button on our pole barn kits page.

Knowing how to make this calculation will make your roof construction project easier and will ensure the safety and success of your roofing project once completed. Cut off one corner of the board at the angle you have set. Roof pitch is a term describing how steep or flat your roof slope is. Find the common rafter incline degree of the unit rise to unit run.

You will need to make 22 5 degree angle cuts on the rafter joist ends that mate up to the top plate or header. Roof pitch angle and slope factor charts. An angle cut is a very common cut needed for constructing rafters for any roof. 45 degrees where the joists meet up with the top plate or header and 90 where the joists meet in the middle at the ridge board.

Use a square to mark a line up into the board 6 inches from the center of one end. This is useful because sometime you may need to cut a bevel with your circular saw that is not calibrated using roof pitch style this setting on circular saws is calibrated in degrees. Flip the board to the opposite corner and cut again so that the angles meet in a peak on the center line you drew. Cut the end of a fourth piece using the same angle from the upper cords.

Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof.