How Far Apart Are Trusses In A Flat Roof

Typical roof truss spacing means that they are usually about 24 inches from centre which means at the centre of one truss there will be a two foot gap or twenty four inch gap until the centre of the next truss.

How far apart are trusses in a flat roof. Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. Typically pole barn style buildings in my area have bays distance between trusses of 5 feet to 12 depending on pitch insulation and height. With this design change roof trusses could be placed 12 feet apart making it possible for roofs to support the loads to which they would be subjected. Spf 2 6 rafters can span 8.

Putting the trusses into place. Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet. Most are spaced between 18 26 inches apart. Their defense is our engineers will not allow us to.

The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length. The same concept holds true for roof trusses. I ve had roof truss manufacturers try to convince me it is impossible to place wood trusses at spacings of over every 4 feet. Most economical when the difference in slope between the top and bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch.

In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. Reader dave in michigan writes. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. Hi i saw on your webpage the pole barn guru stated the trusses could be spaced 12 apart i called and was told it is a double truss one on each side of a post that is on 12 centers.

The tables below give maximum spans for rafters and beams. These standards are as follows. If you move the rafters closer together at 16 o c then your syp rafters will span 11 and spf up to 10. It all comes down to engineering.

That is exactly what i have double trusses on each side of a post on 12 centers. The higher the snow load the closer the purlin spacing required. Once you ve calculated the number of trusses you will need you should purchase the lumber. We suggest 5 on center trusses with flat purlins to be restricted to 30 ground snow loads or less in most instances.

If purlins are laying flat on top of the truss 5 or 6 feet is the max on 2x4 s edge up can go to 12 feet or more.