Hi All

Im a newbie to DIY tiling and need some advice please.

We've recently re-fitted our bathroom and Im not onto the tiling stage. Ive done most of the walls and am now onto the floor. The issue I have is that the floor is 20mm tongue & groove chipboard, which in my ignorance looked nice and flat and so I thought would be a good base to tile to having screwed it down solidly and sealed it. I did a bit of a search on here looking for adhesive recommendations though and stumbled across several threads saying that chipboard is actually one of the worst things to tile to (great!). For reference the area being tiled isn't huge, about 6m2, sitting on 8" joists and I'm tiling with 30cm x 30cm ceramic tiles.

So, given that tiling straight onto the chipboard seems to be a no-no(?), my options seem to be either to rip up the chipboard and put ply in its place which would be a pain and relatively expensive, or to overlay the existing chipboard with thin ply. The second option seems easiest on the face of it, the problems are a small step into the bathroom which isnt desirable, and the bath height would be wrong as its already been set so the side panel sits correctly onto the tile base, adding ply would mean chopping the bath side panel down a bit (which I'd rather not do) or raising the bath which is not an option as it's already siliconed in place and tiled down to.

Are there any other options? I realise in hindsight I should have addressed the floor issue before any tiling etc took place, but its a bit late now unfortunately.

thanks
Chris

Hi Chris, could you not use a uncoupling membrane like durabase ci matting? this will only add 3mm to your floor (+ tiles) i am sure there are plenty of threads on here giving you the pro's and cons. alternativly use a product like no more ply, going over you existing floor.
Lee

to the forum
you could always use 6mm cement or backer boards,allowing you to keep the height to a minimum,or replacing the chipboard with 22mm ply(with extra noggins between joists) will only increase the height overall by 2mm!

Hi Locoblade welcome to the forums

So your options are raising the bath but you don't seem keen, ripping up the floor, but again you dont really want to. If the floor is solid as you say you could overboard it with a product called "no more ply" its relatively cheap and easy to install, screw it down at 200mm centres, its glued down as well, the glue can be supplied with it. You say you have bonded the floor, not with pva I hope, use acrylic bond as it is a far superior product. You are working on a wooden floor so use flexible adhesive and grout, if you have any concerns whatsoever about the original floors integrity then change it for 18mm ply, better to do it now than in six months time.
Goodluck

Hi Chaps

Many thanks for the welcomes and the replies thus far.

Googling Durabase CI membrane, this gives a good base to tile to but doesn't add strength, is that correct? The floor itself is pretty solid but Im sure there's an element of flex there which is one of the main reasons I thought chipboard was a bad surface to tile to, hence the reason to overlay or replace??

No More Ply looks promising too, 6mm is something I may be able to get away with regarding the bath height, I'll have to have a proper measure up tonight to refresh my memory on the exact measurements because I did leave a small amount of leeway as I didn't know the tile adhesive thickness I'd need, so might just squeeze it in.

If No more ply is suitable, where's the best place to source it from? Ive got a fairly local Topps Tiles and CTD, would they stock it?

BTW, the above should obviously read "...and Im now onto the tiling stage".

cheers
Chris

The 2 stores you mentioned will sell hardi backer....6mm as suitable for over laying your floor if deflection is at a minimum...

Thanks Dave, I'll have a look at the weekend to see what they have in stock.

Chris

I have been using No ply recently. Realy easy to use. Try to lay it in the opposite direction to your flooring. Use their own brand glue, but use your own screws as theirs are a bit pricey.