Flat Roof Joist Span Table Uk

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.

Flat roof joist span table uk.

Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Easy to look up tables allow the reader to choose the size of solid softwood timber members necessary to give adequate support to floors ceilings and roofs in dwellings. Joists under each partition. You need to measure the complete span of your floor joists together with the distance between them the centres and the size of the timbers.

The section sizes are based on regularised als or cls timber. Span tables for solid timber joists. These span tables apply only to flat roof and roof with a slope of up to 10 degrees. Surveyors span tables for designing roof rafters.

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. Eurocode 5 span tables for solid timber members in floors ceilings and roofs for dwellings 3rd edition. 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. All the figures are based on the normal loading conditions.

This should be compared to the table. For timber floors between homes. Floor joist span tables for surveyors floor construction. Now in its 4th edition the trada span tables publication is a must for any designer or builder.

Subject ceilings and flat roofs timber sizes and construction details 09 issued 01 04 13 rev page 1 of 2 the following tables give details of the allowable spans and spacing for some of the more common timber sizes used in ceiling and flat roof construction. 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 04 2 75 3 47 4 20 4 93 5 66 floor joists flat roof joists assumptions at 400mm centers supporting permanent load excluding self weight of joists up to 50kg m2. Eurocode 5 span tables. 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.

Tables 1 and 2 in this chapter are derived from the trada technology ltd. Due to variations in timber grades load sets support conditions and bearing widths the tables are not suitable as a design tool.