Roof Joist Member Thickness

Span calculator for wood joists and rafters also available for the android os.

Roof joist member thickness.

This is the distance between joist centres. The lengths and sizes of joists vary depending on the species and quality of the lumber used. Let s consider a basic gable wood roof framing design. For instance if your roof has a steep pitch you may be able to use 2 inch by 4 inch rafters but if your roof has a low pitch building code may require that you used 2 inch by 6 inch or 2 inch by 8 inch rafters.

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. Wood beam calculator american wood council website rafter and joist span faq. Fire safe construction 3 floor performance and tj pro rating 4 5 section 1. Continuing on from part 3.

9 16 tji joists design properties 6 floor span and load tables 7 8 tips for preventing floor noise 8 allowable holes 9 cantilevers 10 11 roof span and load tables 12 13 framing. Here we have a wood framed gable roof. Trus joist tji joist specifier s guide tj 4000 july 2019. For low pitch roofs building codes may require larger dimension rafters.

Floor beam span tables of residential structural design we will now look at roof rafter and beam design.