What to use under bathroom tiles?

[gsport george]

Stripping back bathroom and the walls are a mess of concrete, tile adhesive and lime plaster which has lost it's key. The end result is that the walls are either bare stone rubble, scruffy brick or concrete.

What should I apply to the walls for tiling onto?

I am planning to use some coarse stuff to "re-point" the bricks and rubble (the pointing has mainly come out with the plaster) but what should come next?
I assume lime plaster is not going to appreicate being sealed up behind tiles (probably why the original stuff has lost it's key), so what are the alternatives?

I can use a cement board like Hardibacker or Aquapanel stuck up with dot and dab but it hardly seems ideal (or cheap).

George

 

[gsport george]

Just me then....

Well my plasterer mate has suggested leveling up then dot-n-dabbing on ordinary plasterboard for all but the shower area which will probably be some sort of cement board. I cant see any way of allowing the pointing behind the tiles to breath though...

George

 

[Nemesis]

I think that all are engaged in another thread at the moment!

I'm sure someoen will think about this when the arguments over nuclear power die down - if ever...

But - for small areas I wouldn't worry over much anout the breathability of the interior, as long as you have exterior pointing in lime it should be fine, and ventilation of course.

I'd suggest some sort of board as long as it's well sealed. ie tile grout and sticky stuff, otherwise water tends to make it go all soggy.

 

[Moo]

Well-sealed marine ply?

 

[piper]

What about Tadelakt? http://www.mikewye.co.uk/mikeprices.htm#Tadelakt

 

[piper]

Instead of the tiles, I mean. And does anyone else have opinions or experience of it?

 

[gsport george]

The Tadelakt seems like an interesting alternative.... if it IS an alternative... not sure if it is meant for that kind of job...

George

 

[Penners]

I haven't used this myself, but I've heard good reports of it. Expensive, though.

 

[gsport george]

My local suppliers wont sell the aquapanel in less than a pallet load, which is about twice as much as I could use.... And yes, it is very pricey.

The Hardibacker is expensive enough at £10 for a 1200 x 800 x 1/2"... but at least I can buy single sheets.

George

 

[NT]

Tiling isnt significantly breathable, so using cement board behind wont make it any worse. Just dont use wet cement onto brick or stone.


NT

 

[gsport george]

Tiling isnt significantly breathable, so using cement board behind wont make it any worse. Just dont use wet cement onto brick or stone.


NT

Yes, I didnt really see how it could be. I just wondered if I should try to leave an airgap between the lime mortar and the boards so it could circulate upwards to the untiled areas and so breath....

 

[Nemesis]

How large an area are you doing? What is the house built from?

If it's only small, and especially if upstairs, I think there is little to worry about really.

 

[Gervase]

Agreed - a shower cubicle five feet by three by three isn't going to matter a lot in the great scheme of breathable things.

 

[tony]

cant remember where i read it i think it was professional plumbing magazine. plywood of any grade shouldnt be used in bathroom situations except to line floorboards before titling.

best
regards
tony

 

[CHRIS]

The best way is to use 18mm ply screwed down (not nailed) on the floor every 400mm then use 12mm tilebacker board (I like Wedi but it is expensive but very quick to use) glued down with tile adhesive (flexable BAL is idea for timber framed buildings) and then screwed down the using large 1.5 inch washers recomended.

http://www.wedi.co.uk/tileback.htm

Dont use plaster board or even the green stuff to tile onto as it will not last (like all new build boxes), you can use 18mm ply in the shower cubical for strength but still use a backer board to tile onto - this is the proper way.

Also the tilebacker board is great for underfloor heating as it helps with the transfer of heat back to the tiles.

 

[Penners]

a shower cubicle five feet by three by three ...

Wish mine was that big. Think phone box... think bruised elbows.