Roof Trusses Weight Load

Don t forget to add all roof assembly materials when calculating total roof weight.

Roof trusses weight load.

If you have another floor above your garage the ceiling floor structure can usually support up to 40 lbs sqft including the weight of the floor above it. Is a safe estimate. This translates into a uniform load of 640 plf across 2 5 ft of the span. When it comes to estimating the weight of an existing roof field verification of the in place construction is necessary.

The horizontal bottom chords of most garage trusses are designed to carry the weight of drywall and insulation. The live loads a truss is required to bear are determined by local building codes. In engineering calculations the span of a beam a truss is a beam is squared. For trusses at 2 ft o c.

Safe load per table 4 1 specifies a 2000 lb over a 2 5ft x 2 5ft area. The formula for truss loads states that the number of truss members plus three must equal the twice the number of nodes. Bcll 0 psf no storage available in floor trusses. If the number of members is labeled m and the number of nodes is labeled n this can be written as m 3 2 n.

If you do not have another floor above the ceiling trusses may only be able to hang a maximum of 10 lbs sqft. Scrap of plywood over the chords and set about 40 lbs. The truss is analyzed for each possible location of the 640 plf load along the span. Bcll 0 psf.

If the bottom chord of a roof truss functions as a floor joist such as in an attic room it carries a live load that also varies by use but a typical live floor load for a residential space is about 40 pounds per square foot. Of stuff on it. That means you could lay a 2 x 4 ft. This means a 30 foot span is 50 wider than a 20 foot span but must have 225 of the load carrying capacity.