How To Size Roof Ridge 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.

How to size roof ridge beam.

I always always build trusses. Most interior beams need to include the roof load. In the example d calculates to 7 75. Its the way i was trained to build sheds.

Framing in a ridge beam in shed roof construction is not hard. 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. Calculate the initial value for d then round it up to the nearest inch.

Now if you have done any looking around this site you ll quickly see that i am not a fan of using a ridge beam in shed construction. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Determining the ridge beam height. This tells you the size of the beam needed to support the porch s roof.

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. This means the example porch would need a 6 inch by 8 inch beam. The finished ridge beam height z above the top of the wall will be m plus the y height. Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3.

Here s a picture of a gable style shed using a ridge 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. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam. It has been my experience to never use a beam smaller than a two ply 2 x 8.