Span tables for solid timber joists.
Flat roof joist span tables uk.
All roof timbers including joists wall plates blocking strutting battens firings and noggings must be to be preservative treated unless the timber used is naturally durable.
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.
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.
The section sizes are based on regularised als or cls timber.
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.
Joists under each partition.
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.
For pitched roofs flat roofs and ceiling joists.
Floor joist span tables for surveyors floor construction.
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.
This should be compared to the table.
The following easi joist span tables are to be used as a basic guide to achievable joist span for given depth and spacing and should be used for estimating of feasibility only.
Due to variations in timber grades load sets support conditions and bearing widths the tables are not suitable as a design tool.
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.
All the figures are based on the normal loading conditions.
Eurocode 5 span tables for solid timber members in floors ceilings and roofs for dwellings 3rd edition.
For timber floors between homes.
These span tables apply only to flat roof and roof with a slope of up to 10 degrees.
Timber to be covered these span tables do not apply to timber which is fully exposed to the elements.
Tables 1 and 2 in this chapter are derived from the trada technology ltd.
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.
