I'm going to tile my bathroom floor which is on wooden joists with regular T&G.

Question - how thick should I line the floor with ply or chip board ? 12mm or 18mm ?

I'm going to PVA it to improve the water resistance.

T.

12mm screwed down pva >>>> spot on ,

12mm will do
if the floor is in good nick and flat you wont need to ply it either
just use a good flexible adhesive from bal or ardex

I saw some flexible adhesive in Wickes but it just said it was water resistant not waterproof. So thought I would go the lining route.

The floor is flat and not really that bid 1.5m x 2m.

T.

choice is yours but i wouldnt bother if the floor is flat especially for a small area
ive done around a dozen bathrooms with tyhe flexible stuff but dont use wickes make sure u use bal or ardex

big al
im sure u probably know more about it than me but would hardboard be no better than a solid floor as its quite flexible
personally id say its all (12mmply) or nothing
What dyou reckon
Id hate to give a fellow scooby mate the wrong advice

Thanks Guys, So the bottom line is not wickes cement and line it !

I'll go for it this weekend.

T.

I am doing the same at the moment. All specialists and tilers I have spoken to have stated a minimum of 13mm ply and preferably 18mm.

Defiantly lay ply before hand and spot nail it every 4 inches - that is the bugger but worth it to stop any movement. You can hire spotnailers from hireshops funnily enough :D Same if you were laying carpet tiles too. A decent waterproof muck and grout is imperative for a hardy finish.

Its all done now see here (www.trumble.nildram.co.uk/bathroom/b20.jpg) - I used best part of 200 1.5 inch screews to hold the ply down - but its nice an level and no creaking !

Thanks all.

T.

Looks good Trumble - ceramic floors eminate class don't they :) Got a nice suite to plop in there have you?

Its been going on for a while see here !!! (http://bbs.scoobynet.co.uk/showthread.php?t=320195)

Ive finally got the two units for the loo and sink.

T.

DOH ---- :D:D:D

That was a link to 4-pot breaks :D