Standard Wood Roof Truss Sizes

Essentially a roof truss is a prefabricated frame of supports designed to go on top of a building as it s being built.

Standard wood roof truss sizes.

35 timber size information. A truss of this size and larger usually runs a higher figure of around 4 to 4 75 per foot of truss. Easily attached to the rest of the building s frame they circumvent the complicated expensive nature of from scratch roof framing and can be purchased in a wide variety of designs made from either lumber commonly used for homes or metal primarily used for commercial. Standard framing details for use in preliminary design.

Spaced sheathing or 1x boards may be reduced slightly. You can use sbca s span charts to roughly determine truss sizes available. 0 785 kn m snow load. The truss is a framework consisting of rafters posts and struts which supports your roof.

Member size grade tc 1 4 4 7 97 tr26 bc 6 10 72 tr26 bc 10 2 72 tr26 wb 3 8 5. Girder trusses are designed to carry additional loads other than standard roof loads. This is the distance between trusses. 600 timber thickness mm.

The steeper the roof the more expensive the trusses get because the longer the boards get and the more roof area increases. Spans for 2x4 top chord trusses using sheathing other than plywood e g. 0 250 kn m ceiling live load 0 250 kn m tank load 0 450 kn max tile batten centres. The important point to keep in mind when you use your truss calculator is that every truss calculation is completely unique and is based on the size of your roof and its specific dimensions.

The standard roof truss spacing is 2. A truss with the same pitch and heel on both sides and a peak at the center is called a common truss. This truss has a 30 span which is only 4 more than 26 but look how much more webbing there is. Standard roof truss general load settings.

The webbing is necessary for the strength of the truss and it is needed in a truss this size. Included are a series of representative roof truss span tables that will give you an idea of the truss spans available for a particular load condition load duration lumber type and truss configuration. Trusses must be designed for any special loading such as concentrated loads from hanging partitions or air conditioning units and snow loads caused by driftingnearparapetorslide offfromhigherroofs. 360 mm general truss information.