How To Size Roof Ridge Beam

This calculator matches up with 90 of the applications in the 2012 international residential code book.

How to size roof ridge beam. The finished ridge beam height z above the top of the wall will be m plus the y height. This means the example porch would need a 6 inch by 8 inch beam. If you know the slope x in 12 you want to use for your roof framing design you can use it along with the run r to determine the height of the ridge beam for example if the slope is 4 in 12 and the run is 12 feet the ridge beam height m will be 4 feet. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam.

Because a ridge beam often carries a significant area of roof load they can exhibit structural distress due to a defect in wood impact on the roof or use of an undersize beam. This tells you the size of the beam needed to support the porch s roof. Here s a picture of a gable style shed using a ridge beam. I always always build trusses.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Its the way i was trained to build sheds. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to.

If there is are any questions about anything else then you should contact your supplier or an engineer. Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3. Determining the ridge beam height. Calculate the initial value for d then round it up to the nearest inch.

Most interior beams need to include the roof load. The ridge beam shown below at the living room of a 1950s modern style ranch house in gainesville has cracked at mid span and is slowly heading towards failure after. Ridge beams and boards modern raising ceiling joists jlc technical steico construction roof rafter collar tie calculations structural ridge beamtimber steel framing manual single span ridge beamglulam ridge beam span table elcho. Framing in a ridge beam in shed roof construction is not hard.