Live Load On Roof Truss

Live loads are not always present.

Live load on roof truss. I for sloping or flat roof with slopes up to and including 10 degrees. The live loads a truss is required to bear are determined by local building codes. Sec 07 version 2 0 handout section 07 codes load types problem 3 given. The live load shall be taken as follows.

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. Dead loads are always present. With single 4x2 chords designed to support the following loads. In other words on a steep roof less material would be stacked in a concentrated area at one time to avoid having it slide off.

Where snow isn t a problem the live load can come from people working on the roof and any equipment they take on to the. Examples of live loads are snow wind rain and temporary construction loads. A when access is provided 1500 n m 2 b when access is not provided 750 n m 2 except for maintenance ii sloping roof with slope greater than 10 degrees. Floor live load 40 psf.

The live load on a roof is the weight of any temporary objects on the roof. Live loads on roof trusses. If unbalanced snow loading isn t required or specified the truss designer may enter the 25 psf snow load as a top chord live load tcll set the load duration factor to 1 15 for snow and turn snow loading off completely. Or the 25 psf snow load could be entered as a roof snow load with the unbalanced snow loading option turned off.

In my region on cape cod we have a ground snow load design of 25 psf which is a greater design load than the live load 12 psf to 20 psf over an entire roof system. Roof truss basics roof trusses are engineered wood alternatives to hand framed rafters. However if the attic is intended for storage the attic live load or some portion should also be considered for the design of.