Notching Roof Rafters

Laying out hip valley and jack rafters takes experience and skill but if you re building a simple gable or shed roof all you need is the common rafter the basic building block of roof framing.

Notching roof rafters.

Other rules in compliance with the international residential code irc r502 8 and r802 7 are. Structural roof members shall not be cut bored or notched in excess of the limitations specified in this section. More truss makers are switching to drop gables where the only notching is on the 2x6 outrigger itself. To lay out a common rafter you need the pitch of the roof expressed in units of rise per foot of run in the gable roof example shown here a rafter with 6 in 12 pitch rises 6 in.

Notches in solid lumber joists rafters and beams shall not exceed one sixth of the depth of the. Rafters are commonly spaced about 24 inches 61 cm apart. The number of rafters needed will be determined by the length of your roof. Simple jig to cut your birds mouth notches.

Up here notching the gable end truss is common it is done to support the lookouts and fascia on the end of the gable. Notching roof rafters to headers the new roof will start at the back of the house go up to a peak and then down to rest on the entrance header to the kitchen. All roof rafters should be identical so follow the same steps to measure the plumb cut tail cut and birdsmouth cut. Click here to download a full notching and boring guide for joists and studs from the wwpa.

Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. R802 7 cutting and notching. Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. In general never make notches in the middle third of the joist where the bending forces are greatest.

Please consult a professional before making any cuts i am not a professional framer or roofer nor do i claim to be. I noticed that the lumber don t know whether to call them joists or rafters comes down from the peak and they had to notch it.