Floor joist span

20 Oct 2010
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United Kingdom
Looking for a bit of info so shall be asking possibly dumb questions in the foreseeable future.

But firstly,

For a 4.8m clear span would C24 220x72 at 400c/s be suitable?
There will be a NLB wall running perpendicular.

2 storey ext, no bath.

Sorry if thats not enough info.
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Wouldn't engineered joists be better?
Do you mean like posi-joists? For ease of electrics/plumbing etc.. or cost saving? i.e more cost effective than buying 5m lengths of 9x3 c24 timbers
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There may be a cost saving plus ease of services, I was thinking more of the ease of handling and supply of such chunky timbers.

I've not checked the prices of engineered joists for a long while, so I'm not sure of cost comparisons, but it used to be favourable for long timbers of large section sizes
Would floor/ceiling levels be a problem 'mixing' timbers with engineered? Don't want unsightly steps etc...
Using 9x3 timber perpendicular to the engineered joists, not mixing them!
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You can always pack out with 2x1s or 2x2s to make the ceiling levels marry up

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