For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
2 x8 roof purlin span table.
Rafter spans are tabulated for the most common roof loads.
Span calculator for wood joists and rafters also available for the android os.
The loads are based on adjusted roof snow.
If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts.
View joist rafter tables.
See a 1 3 for 2 span floor joist requirements.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
For special conditions not covered in the tables or for selecting sections for a speciļ¬ c application contact your supplier.
The standard of purlin length will vary anywhere between 100 to 300 mm while the thickness will vary anywhere between 1 to 3 mm.
Also available for the android os.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
For example in the joist span table below the highlighted cell shows that 2 x 8 southern yellow pine joists that have a grade of 2 and 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.
These tables can also be used to determine deck joist span.
Table 9 2 adjustment factors for alternate loading and spacing conditions for determining required com.
Use these two tables for.
Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
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.
Can 2 4 roof purlins span 12 feet.
Hi i saw on your webpage the pole barn guru stated the trusses could be spaced 12 apart i called and was told it is a double truss one on each side of a post that is on 12 centers.
Span tables for flat roof joists to bs 5268 7 2 imposed loads of 0 75 kn m for maintenance and snow load are applicable where there is no permanent access no fixed ladder or staircase and most areas where the altitude does not exceed 100 metres refer to bs 6399 3.
Notes symbols ae in 2 effective area of the section for axial loading area in 2 full unreduced cross section area of the section.
Reader dave in michigan writes.
For 2x4s purlins the posts are spaced in 4 feet distance.
My question is can i use 2 x 4 on edge spaced.
