Roof Truss Thickness

The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.

Roof truss thickness.

8d ring shank nails should be used instead. Roof sheathing standard roof sheathing which consists of 4 by 8 sheets of plywood or oriented strand board or osb is 1 2 inch thick and attaches directly to the roof rafters or the roof trusses. When it comes to using osb or plywood for gussets vogt says that osb is more commonly used. The typical thickness range for sheathing is 3 8 to 3 4 inch.

Overview of trusses use of trusses in buildingtrusses are used in a broad range of buildings mainly where there is a requirement for very long spans such as in airport terminals aircraft hangers sports stadia roofs auditoriums and other leisure buildings trusses are also used to carry heavy loads and are sometimes used as transfer structures. Roof truss factors to consider. This could be for fink trusses in a house construction or queenpost trusses for a garage. Sheathing should be a minimum of 19 32 inch thick.

Pitched roof timber sizes. The thickness of the material used for the gusset also affects the span rating that is how far apart the trusses can be spaced along the roof. The thickness of plywood used for roof decking depends on the roof slope the spacing of rafters and the weight of other material to be put over the decking as well as the design load the. The sizes of the wood used range from 2 6 and 2 8 even though its thickness can be based on the weight that it will support and the overall size of the roof.

Fine thatching grass or reed should have a 1 2 2 5 mm stem butt diameter. This is the right way to fix truss clips connecting the rafter and wall plate. Building roof trusses for your home. This rafter truss calculator has a range of applications including being used as a wood truss calculator roof truss calculator roof rafter calculator scissor truss calculator or for roof framing.

In general a roof truss manufactured from 2 by 4 lumber will support as much roof load as a 2 by 6 or 2 by 8 rafter. We usually opt for the 35mm thickness in timber when designing standard roof trusses. Never attach roof sheathing with staples. Meanwhile the 46mm thickness option is used for attic trusses due to fire regulation guidelines.

If rafter construction is used instead of roof trusses and the roof covering is regular sheeting or tiles. The minimum thatch layers and thickness vary depending on the type of grass or reed used for thatching.