Timber Roof Joist Span Tables

Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

Timber roof joist span tables. 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. 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. Span calculator for wood joists and rafters also available for the android os. These span tables apply only to flat roof and roof with a slope of up to 10 degrees.

Ceiling joist span use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. Also available for the android os. Timber floor joists shall be adequate for the spans and loads and be correctly installed. 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.

Surveyors span tables for designing roof rafters. Span tables span tables can be used to determine the size of a timber member of a particular strength class required for a given span. Solid timber joist sizes are provided in the bs 8103 3 span tables. Simplified span tables for southern pine lumber and glued laminated timber glulam headers beams and girders.

View allowable load tables. Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall. For pitched roofs flat roofs and ceiling joists. 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.

View size selection tables.