Garage Roof Joist Spacing

This is the distance between joist centres.

Garage roof joist spacing.

If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. If the roof is not completely square you can decrease the space between joists but never increase the space. The table states that 2 x 6 rafters spaced 16 inches on center o c can span a maximum distance of 13 feet 5 inches. For example the highlighted cell below shows that a 2 x 6 southern yellow pine joist with a grade of 2 and spaced 24 apart can have a maximum span of 10 feet 0 inches 10 0 if you are designing your structure to support a plaster ceiling.

Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet. Joist spacing of 24 inches is allowed for spans between 16 to 20 feet using 2 inch by 10 inch lumber of these three grades. Not more than 0 5 more than 0 5 but not more than 0 75 more than 0 75 but not more than 1. Two options that arise could be your wider 24 and your narrower 12 options for spacing.

Pole barn roof truss spacing generally tens to operate according to similar spacing principles though there are some proponents of having higher pole barn roof truss spacing. Centre to centre spacing of joists in mm joist size width depth mm 400 450 600 400 450 600 400 450 600. Another option are 2 x 8 rafters spaced 24 inches o c. 2x8s are used frequently for these projects.

Dead load per square metre in kn m supported by joists. So the space between rafters can be greater without reducing the maximum span. In making your choice consider how you will insulate your insulate your roof. Variations in ceiling construction nonparallel ceiling joist designs require additional support construction in the ceiling.

In many circumstances 16 inches would be your standard spacing for shed floor joist but this is just a rough guideline. Permissible clear span metres. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. The same concept holds true for roof trusses.

Usually 400 450 or 600mm but any value can be used up to 610mm max. 2 8 s come standard at 1 inch thick. Especially when steel roof truss spacing is concerned some engineers would argue that it is possible to only have a roof truss spacing of four feet off center even eight feet has been suggested.