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Timber & Steel

Timber & Steel

Timber & Steel reviews, comparisons and buying guides from Build Journal.

All Timber & Steel guides & reviews

Floor Joist Sizes and Spans: A UK Guide to C16, C24 and Spacing Timber & Steel 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. 8 min read