Roof Ridge Beam Span Table

Let s consider a basic gable wood roof framing design.

Roof ridge beam span table.

Keep in mind that these are maximums in other words shortening spans slightly will result in a more solid structure. 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. A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to. According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2.

Anything 5 and above we always at least double cripple. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Refer to sfpa s publication southern pine headers beams download in publications that includes all size selection and allowable load tables.

The figures are based on quality materials. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam. Beams of more than one ply must be fastened together with either nails or bolts. Versa lam laminated veneer lumber lvl beams and headers eliminate twisting shrinking and splitting and deliver flatter quieter floors and structures.

Here we have a wood framed gable roof. Also see assumptions for table development. Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3. Floor beam span tables of residential structural design we will now look at roof rafter and beam design.

Engineered wood products ewp lvl span and size charts. On longer spans the beam may require much more bearing space as indicated by this table. Continuing on from part 3. 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.

Loading conditions are detailed below. For each application a pdf download is available. For lesser grades spans should be shorter. 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.