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Flat roof joists - sizing and span tables
4B.14NI-wide·Technical Booklet D Structure
Tables 4B.35 to 4B.38 give the maximum clear span of joists for a flat roof using timber strength class C16 and C24. The sizes, spacings and spans given will safely support the dead loads stated in th
structuraltimberflat-roofTimber section sizes and processing for flat roof joists
4B.14NI-wide·Technical Booklet D Structure
The section sizes are either sawn across the timber thickness in accordance with tolerance class 1 of BS EN 336 and processed in accordance with tolerance class 2 of BS EN 336 across the timber width
structuraltimberflat-roofFlat roof joist span and spacing definitions and minimum bearing
4B.14NI-wide·Technical Booklet D Structure
Tables 4B.35 to 4B.40 are for a slope of up to 10° from the horizontal. Clear roof joist span is the clear dimension measured horizontally between supports. Take the roof joist spacing as the dimensio
structuraltimberflat-roof