Floorboard sizing and joist spacings

[Tim W]

Long term this - but while I'm up in the roof pulling wires, I started thinking...

I want to reboard the dormer with *non T&G* (for easy lifting) normal floorboards. No ply, no chipboard, nothing that's a PITA to lift for access to cables.

My joist spans are:

400mm in the roof voids (light boarding here for storage, direct onto ceiling rafters, 4x2").

500mm on most of the strengthened parts of the main floor (8x2" and a few

4x2" packed up - yes I know...)

600mm span in *one* place.

The 600mm span might get an extra joist in there, or at least the 4x2" packed up.

So how do you decide what thickness of 6" or 8" floorboard can cope with 400 and 500mm spans for both light storage and normal flooring? I'm thinking of "normal" floorboards or maybe something reclaimed. All will be screwed down. But if I have to go thicker, that's fine.

We have to assume normal usage (eg maybe a bed) but we will probably have our lounge up there. Pianos unlikely.

Cheers

Tim

[Stuart Noble]

I think you'll find 6" x 1" is the standard. Jewsons used to do whitewood flooring, which was cheaper than redwood, and better behaved

[Tim W]

Stuart Noble wibbled on Tuesday 06 October 2009 16:52

Thanks Stuart - that's handy info re: the whitewood.

Cheers