Roof Truss Thickness

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.

Roof truss thickness.

Pitched roof timber sizes. 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. 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. Roof truss factors to consider.

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. This could be for fink trusses in a house construction or queenpost trusses for a garage. Never attach roof sheathing with staples.

The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction. 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. Fine thatching grass or reed should have a 1 2 2 5 mm stem butt diameter. Meanwhile the 46mm thickness option is used for attic trusses due to fire regulation guidelines.

The minimum thatch layers and thickness vary depending on the type of grass or reed used for thatching. When it comes to using osb or plywood for gussets vogt says that osb is more commonly used. 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. Sheathing should be a minimum of 19 32 inch thick.

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 typical thickness range for sheathing is 3 8 to 3 4 inch. Structural engineers certify and design roof trusses. If rafter construction is used instead of roof trusses and the roof covering is regular sheeting or tiles.

8d ring shank nails should be used instead. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.