Flat Roof Joist Span Tables

The tables below give maximum spans for rafters and beams.

Flat roof joist span tables.

Flat roof joist calculator. 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. Span tables all span tables. The full version allows any size.

Surveyors span tables for designing roof rafters. View joist rafter tables. Span tables for solid timber joists. Span tables use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

Timber floor joists shall be adequate for the spans and loads and be correctly installed. Joist and rafter span tables. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. These span tables assume installation of at least three joists or rafters that are spaced not more than 24 on center.

Span calculator for wood joists and rafters also available for the android os. Also available for the android os. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. These span tables apply only to flat roof and roof with a slope of up to 10 degrees.

The figures are based on quality materials. The calculated spans assume fully supported members properly sheathed and nailed on the top edge of the joist or rafter. Where the tables do not apply or where there are concentrated loads floor joists should be designed by an engineer in accordance with technical requirement r5. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

1 enter joist details 1 1 span and joist spacing. Straight line interpolation shall be permitted for intermediate spans and design values. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

This demo version is fixed at 1m clear span. Solid timber joist sizes are provided in the bs 8103 3 span tables. Joists rafters simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Span tables can be used to determine the size of a timber member of a particular strength class required for a given span.

For pitched roofs flat roofs and ceiling joists.