polystyrene under chipboard flooring

[jim_gps]

Hi,

Advice needed....

I'm renovating an old office and I'm intending to lay 22mm T&G chipboard over the existing floorboards as they are very old, a little uneven, and unsuitable for carpet tiles. I was wondering whether it would be helpful to put 10mm-25mm of expanded polystyrene under the new chipboard to take up some of the bumps and lumps of old nails, damaged boards etc as well as possibly improving the sound insulation between floors. Is there any possibility that the polystrene and the chipboard could react over time? Would a wood pulp sheet material be more suitable.

Best regards,

Andy

[The3rd Earl Of Derby]

I think you would be better of with sheet material layed down(chipboard) rather than T&G but you will still have to knock in any protruding nails/screws.

-- Sir Benjamin Middlethwaite

[John Cartmell]

Knock the nails in. Look at the sort of underboard solutions there are for laminated floors. Decide what you want the material for - the polystyrene may make most sense for insulation and be too expensive just to make it more even.

[Ian Stirling]

I think you would be better of with sheet material layed down(chipboard)

Actually, as long as they protrude less than the polystyrene is thick, they'll just punch into it, with no impact on the chipboard.

[Christian McArdle]

It may be better to remove the floorboards before laying the chipboard.

Christian.

[Dave Plowman (News)]

This is how the ground floor of a mate's house is constructed, but over concrete rather than floorboards. So there's no reaction between the poly and chipboard. I doubt it will help much with sound insulation to you, but might help the transmission of footsteps downwards. It should help with heat insulation, though.

[Rob Morley]

That's what he's using

Why? They'll just dig into the EPS.