Spacing Between Roof Trusses

If your local building authority has a rafter spacing code you may not space rafters wider than required by code.

Spacing between roof trusses.

Roof truss is the structural frame bridging one side of the roof to the other side. When constructing a roof framework the rule of thumb is that any purlin should have a minimum nominal depth and width of 76 mm or 50 mm and max centre to centre spacing between the purlins ought to be 1 2 m. Joints between purlins next to one another should be staggered. But the tables that follow are a lot more specific.

You will also incur additional costs because it is much harder to deck and shingle a roof that is 12 12 pitch versus a 4 12 roof. Roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16 size of rafters in mm 400mm 450mm 600mm. Rafters must be strong enough to hold the roof sheathing and the shingles. The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length.

Rafter boards are fastened to the ridge board at the peak and the top plate where they join the wall. Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches. Basically it is like longitudinal beams that support the whole roof preventing the roof from collapsing. The steeper the roof the more expensive the trusses get because the longer the boards get and the more roof area increases.

The standard roof truss spacing is 2. Other relevant factors include the type of wood being used for the rafters the size of the rafters and the load that the rafters need to support. Spacing is usually used to describe the space between each truss or usually called the bay. Follow this guide to ensure the spacing and stability of your diy roof trusses.

In finished space insulation is placed between the rafter boards and drywall or other material is fastened to the face. Engineers have since determined however that the physical design of a post frame building will allow for standard spacing as great as 12 feet from the center when using high quality metal connector plates and lumber. To determine how many trusses to create you will first need to measure both the width and the length of the structure you are building. The spacing between rafters in a given building is part of the engineering calculations that determine the required structure of the roof.

Determining the correct roof truss spacing as well as the correct materials and how to build your roof trusses will be largely if not completely dependent on the weather that you can expect to receive in your part of the world.