Roof Support Beam Spacing

The tables below give maximum spans for rafters and beams.

Roof support beam spacing.

As most building these days are using those pre made trusses on the roof 24 inches become the main size for any roofing construction when it comes to its truss installation. A roof with a 1 2 pitch or a rise of 1 2 the width of the building and a run of 12 feet. What if we needed to span more than that. Our floor joist beam can span a maximum of 13.

Let s say our house is 24 x 26. For example for copper tubing support spacing varies from 8 ft for 1 tubing to 12 ft for 4. For example the spacing of pipe supports on a 6 line will be approximately 6 10 16 feet. A roof with a run of more than 23 feet.

The rafter length is 16 11 6 or 16 feet 11 6 12 inches. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. For example if the run is 27 feet find the length for 23 feet then find the length for 4 feet and add the two. Now we will need to support that center floor beam with posts.

The typical standard for the spacing on the roof trusses is 24 inches. The typical spacing standards for residential and commercial buildings are about 1 to 2 foot. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. References journal of light construction.

The support system for the roof is comprised of ridgepole and rafters or purlins. This spacing changes at high temperatures and for materials other than steel. With rafters it runs in perpendicular from the walls to the ridge while with purlins it runs to the ridge in parallel. The figures are based on quality materials.

This is most likely the standard size that you will find on pre made roof trusses. In the table above the widest floor beam span for 12 of supported floor joists is 14 7 if using a 5 ply 2 x 12. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Continuous span beams are beams supported at three or more points along their length.

Single span beams are beams supported at two points only. For the purpose of using these tables span may be interpreted as the clear distance between supports measured along the beam.