Roof Ridge Beam Sizing

A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to.

Roof ridge beam sizing.

Ridge boards shall be at least 1 inch nominal thickness and not less in depth than the cut end of the rafter irc section r802 3. Loading conditions are detailed below. Most interior beams need to include the roof load. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam.

Ridge beam height above top of slab height of wall z. If you size a roof beam like a structural ridge that has a l 240 limitation you would multiply the minimum e value by 0 666 785 000 x 0 666 522 810 in this case. Rafter to ridge beam connection framing roof ceiling construction structural ridge beam absolute deflection in a ridge beam structural ridge beam tricks of the trade. Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12.

It has been my experience to never use a beam smaller than a two ply 2 x 8. Once the ridge beam has been positioned in place and supported by roof framing members you can determine the placement of a rafter by measuring down from the top of the beam y height and making a mark on the beam. Sizing ered beam archives load bearing wall removal. This calculator matches up with 90 of the applications in the 2012 international residential code book.

For each application a pdf download is available. Fv does not change when you double the thickness. The formula for determining the finished height of the ridge beam from the top of the slab to the top of the ridge beam is. Refer to sfpa s publication southern pine headers beams download in publications that includes all size selection and allowable load tables.

Make sure the shear value fv for the species and grade you use exceeds the fv listed in the span table. Also see assumptions for table development. If there is are any questions about anything else then you should contact your supplier or an engineer.