Shed Roof Joist Size

To size joists and rafters use the maximum span tables for southern yellow pine.

Shed roof joist size.

Hi there the 47mm x 67mm mini joist hangers are no issue if they are put in an accurate and stable manner. In many circumstances 16 inches would be your standard spacing for shed floor joist but this is just a rough guideline. 2 4 rafters can span up to 7. However the timber sizes you have opted for will prove to be an issue.

For example you can span a 1 grade no knots southern yellow pine a greater distance than a 2 grade with knots southern yellow pine. 2 8 s come standard at 1 inch thick. For light load roofs 24 o c. In other words if there is a 1 1 2 ridge board nailed into the wall and the width of the lean to is 96 then the run will be 94 1 2 96 1 1 2 94 1 2.

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. More roof calculators roof truss calculator. This rafter span calculator is species specific for douglas fir hemlock etc. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads.

The run for a lean to shed rafter ending into a wall should account for the ridge board nailed into the wall where the tops of the rafters rest into. The fact that they are 2x4 will mean that the timber will become curved within 2 years from the weight. Trying to find what size lumber to use. The lengths and sizes of joists vary depending on the species and quality of the lumber used.

Two options that arise could be your wider 24 and your narrower 12 options for spacing. 2x8s are used frequently for these projects. For example in the rafter span table below the highlighted cell in the 40 live load table indicates that 2 x 8 southern yellow pine joists that have a grade of 2 that are spaced 24 apart can have a maximum span of 10 feet 3 inches 10 3 if designing for a live load of 40 lbs ft 2. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.

For heavy loads 2x4s can span up to 5. Rafter and joist span faq. This is the distance between joist centres. This is due to the fact that the timber is 5mts long.