Technical Booklet D Structure·Page 29·Table 4B.4
Strutting positioning for floor joists by span
The number and position of strutting rows depends on joist span: no strutting for spans up to 2.5 m, one row at mid-span for 2.5–4.5 m spans, and two rows at one-third span positions for spans exceeding 4.5 m.
Table 4B.4 Strutting to joists
Joist span | No. of rows and position of strutting
Not greater than 2.5 m | None
Greater than 2.5 m but not greater than 4.5 m | 1 at mid-span
greater than 4.5 m | 2 at one third span positions
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