Timber & Steel

UK timber guides from Build Journal: floor joist sizes, grades and spans, plus a free timber and joist calculator for lengths and quantities.

All Timber & Steel guides

Floor Joist Sizes and Spans: A UK Guide to C16, C24 and Spacing A practical guide to UK floor joist sizes and spans: C16 vs C24 grades, common sizes from 47x100 to 47x225, how 400, 450 and 600mm spacing changes the span, and why you should confirm against span tables or a structural engineer. 9 min read

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