How To Cut Roof Rafters Angle

Roof pitch is measured in a rise to run ratio with the vertical rise always shown first.

How to cut roof rafters angle.

Birdsmouth joint how to cut a birdsmouth and how to cut and install roofing rafters and joists. A rafter or speed square will have marks for both of these angles. The roof on this shed is a 4 in 12 slope which makes it a 18 and one half degree angle on the board ends. If you re framing a gable roof on a new house or building a shed or even a doghouse with a gable roof you ll need to cut a number of roof rafters.

A seat cut is a horizontally level cut so the rafter can sit flat onto the wall plate. So if your roof is a 45 degree angle that is for every 12 along the horizontal run it rises 12 it s a 12 12 pitch. If it rises only 6 for every 12 it s a 6 12 pitch. The ridge end of the rafter and often the eve end will need to be cut to the angle of the roof slope.

Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter. 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. Enjoy the videos and music you love upload original content and share it all with friends family and the world on youtube. A birds mouth is a combination of the two cuts made so the roof rafter sits tightly onto the wall plates square edge.

In this diy guide you will learn how to install a roofing joist or rafter that includes how to work out the pitch of a roof cut a ridge or plumb cut at the correct angle work out the correct length of joist you need and the exact location for a birds mouth joint how to correctly cut a birds. The roof rafters provide integral structural support to the roof.