Flat Roof Timber Joist Span

Notches are not to exceed 0 125 of the depth of the joist and are to be located between 0 07 and 0 25 of the span from the support.

Flat roof timber joist span.

The lengths and sizes of joists vary depending on the species and quality of the lumber used. Herringbone type timber 38mm x 38mm. Rafter and joist span faq. One row when the span of the joists exceeds 2 5m.

This is the distance between joist centres. Joists for that span would normally be around 9. For timber floors between homes. Eurocode 5 span tables for solid timber members in floors ceilings and roofs for dwellings 3rd edition.

They also tell you what the maximum spacing should be between each section or timber member size of joists mm clear span c16 joist m clear span c24 joist m 47 x 95 47 x 120 47 x 145 47 x 170 47 x 195 47 x 220 1 77 2 40 2 89 3 38 3 87 4 36 2 05 2 67 3 22 3 77 4 31 4 85 assumptions at 400mm centers. Usually 400 450 or 600mm but any value can be used up to 610mm max 1 2 timber strength class and joist size automatically calculate sizes suitable for supporting the loads below. Tables 1 and 2 in this chapter are derived from the trada technology ltd. You def cant put a joint in the timber.

Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Should refer to trada document span tables for solid timber members in floors ceilings and roofs excluding trussed rafter roofs for dwellings or ask your lbc surveyor for advice. Two rows or more when the span exceeds 4 5m. Maximum clear span of flat roof joists in metres for sc3 timber spacing between joists size of roof joist 400mm 450mm 600mm 47 x 97 1 84 1 81 1 74.

Although i think you can get 6 metre joists in 6 x 2. These span tables apply only to flat roof and roof with a slope of up to 10 degrees. Span calculator for wood joists and rafters also available for the android os. If you want 6 joists you need a steel midway.

Also available for the android os. The section sizes are based on regularised als or cls timber.