Material for Bathroom floorboard

[mrbg07546]

Hi on the joists we have ripped some chip board which old bathroom used to sit on on.

What's the best material to replace this with. I heard there's some good tile board. Or would I still need a chip board and then put this on top? Thiughts

 

[Gerrydelasel]

You still need chipboard, plywood or floorboards.

 

[JohnD]

chipboard is an awful material, especially in a room that contains water.

WBP ply's the thing to use.

 

[Gerrydelasel]

Hmm, I wonder if it works out cheaper to use chipboard and then a thin layer of ply on top for water resiliance? (cause 18/22mm ply's expensive)

 

[JohnD]

For my kitchen, I had to order-in spruce flooring ply in 8x2 sheets, it is very rough, but subsequently I've used hardwood faced 18mm WBP ply at about £30 per 8x4. I can get flooring chipboard at about £10 per 8x2. Discounts come off these.

For a bathroom, the amount needed is small enough for the cost of the better material not to matter.

8x2 sheets are easier to carry around.

I cut up my sheet materials in the garden and carry the pieces upstairs. Edges need to be sealed for a bathroom, I use water-based varnish.

 

[Deleted member 174758]

I know John hates chipboard, but, 18mm P5-grade chipboard is pretty waterproof and a thin layer of 4 or 6mm hardwood plywood over it then screeded should be fairly good. The chipboard comes in T&G sheets 2400 x 600mm and a D4 waterproof glue such as Everbuild D4 should be used for the joints (NOT D4 polyurethane, however, as that stuff expands and blows the joints). For smaller areas such as bathrooms 18mm WBP plywood is an option instead of the T&G chipboard, although better asealing can be had if the board edges are grooved and a thin (6mm) plywood slip is glued into the joints (so, similar to T&G), again with D4 glue. In both cases the D4 glue can also be used to seal the outside edges of the flooring material (although TBH even old gloss paint will do that just as well). This can be important in upstairs shower rooms!