Tiling

[kambites]

Daft question perhaps, but what is the correct material to tile (wall and floor) on top of? It seems that plasterboard is a bad idea because it absorbs water... the Americans have something called "concrete backer board" but I can't find any references to that in the UK... any ideas?

[billynomates]

kambites said:

Daft question perhaps, but what is the correct material to tile (wall and floor) on top of? It seems that plasterboard is a bad idea because it absorbs water... the Americans have something called "concrete backer board" but I can't find any references to that in the UK... any ideas?

Heres one product.

http://www.wedi.co.uk/home.php

[Agoogy]

Emulsion over the plasterboard or use mixture of water and PVA to seal it prior to plastering...

[s,one]

kambites said:

Daft question perhaps, but what is the correct material to tile (wall and floor) on top of? It seems that plasterboard is a bad idea because it absorbs water... the Americans have something called "concrete backer board" but I can't find any references to that in the UK... any ideas?

We tile on moisture resistant plasterboard which is then unibonded, adhesive which is also waterproof and similar grout.Never seem to have any problems.
On floors we deck floorboards with ply and use a flexible adhesive and waterproof grout.Obviously on concrete we aply direct unless the concrete is still green and we will then apply a latex membrane.

Steve

[kambites]

Thanks guys.

So I think I'm going to:

Put up water resistant plaster board
Unibond the gaps
Seal everything
Then tile over the top of that

[jbswagger]

There is one in the UK called Hardibacker, you can get it in most of the DIY sheds.

http://www.jameshardie.com/homeowner/backerboard.s...

[Emsman]

Hardibacker is a good bet.

If the plasterboard is existing, you can tile over that, if you give it a couple of coats of unibond first.

DO NOT paint over anything prior to tiling. The weight of the tiles and adhesive will pull the paint off the boards, and bring the whole lot down.

In a similar way, if any existing boards are skimmed, check the condition first as the same as above can happen.

If you are using hardibacker (which is the ideal thing) you can go straight over it.

Always use a waterproof adhesive, and a waterproof grout.

I wouldnt use a ready mixed grout though- they are hells own job to acheive a neat finish with.

Get a decent quality adhesive trowel, and a good grout float (as opposed to a squeegee type)

When spreading the walls, apply the adhesive in 1 direction only (ie vertical or horizontal) this will make placing the tiles far easier, as you dont get air caught behind them, allowing you to get a good, flat surface.

For floor tiling, over screed you can use a non flexible adhesive. Over timber, you need a flexible type. Again, i would be inclined to use a 2 part that you mix yourself- they give a far stronger bond. This will of course need a flexible grout, and i would again only use one that you mix yourself. Its not the most pleasant job with a flexible grout, the advantage of one you mix yourself is that you can do small quants at a time.

If you need any help with setting out, or anything more at all, please get in touch via this forum (as i can check it at work) or via my e mail (which i cant check until i get home tonight.

I realise in posting this i am putting myself up for being questioned, but was a tiler for 10 years, and in the industry for 17.

If you need anything else, please ask

Good luck

[krazykris88]

pay someone to do it for you?

[kambites]

How much does hardiebacker cost in comparison to water resistant plaster board? The whole room needs new plaster board anyway (it's all damp).

Oh and if tiling onto plasterboard, do you need to fill in the gaps between the sheets or just leave them open and out the adhesive over the top?

Edited by kambites on Tuesday 19th August 14:41

[Neil_Sc]

Be careful of some of those "water resistent" plasterboards, in this case the definition usually means that it will not decay on contact with water, but it will pass the water through and therefore if this backs on to other plasterboard, that could end up being damaged.

I did my bathroom last year and used Knauf Aquapanel which is a concrete tile backer board.

I then used a tanking solution to prevent water going through it and tiled on that.

Edited by Neil_Sc on Tuesday 19th August 14:50

[Emsman]

Not sure on the cost of hardibacker anymore to be honest, i would guess about 16 a sheet??

No real idea though, and cant look as work mail locked right down.

Is all of the existing damp?? If not, cut out the damp sections, and replace with new, and keep the cost and disruption down by retaining what you can??

As for the joints, the important thing is to screw the edges of the boards securely, so they stay flush. Make sure you use brass screws, as anything else will corrode, and the potential to pop the lot is then on the cards.

Tape over the joints when you are happy that they are flush, coat with unibond (3 or 4 to one will be sufficient)

You can then spread the adhesive over in the normal way (do take on board the tip about going in one direction-it will make life much easier as the pattern of the comb leaves ridges in the adhesive-if these go in one direction, no air can get caught, and the tiles will go on flush)

Normal water resistant plasterboard is more than up to the job in order to keep the cost down though, just use brass screws, and unibond prior to tiling.

BAL make a good range of adhesives, but i would avoid combined adhesive/grout. It may mean going to somewhere a little more specialised than B&Q or similar, but you will get a far better job at the end of it.

Hope you got you e mail.

[Neil_Sc]

It is worth investigating what the tile backer board offers if you go for this route, Wedi board IIRC doesn't need tanking and prevents water from going through it, Knauf Aquapanel is cheaper but requires tanking to prevent water going through.

I ended up going the Aquapanel route and used a tanking solution from Bal Adhesives.

[B16 RTT]

Plasterboard would be fine provided you use this: -



Prime plasterboard
Tape all corners, joints etc
Coat with waterproofer
Leave to dry
Tile

If you need any information call Middlesex Tile Centre on 0208 848 7391. They do all of that stuff and deliver your way as well!

HTH

Edited by B16 RTT on Tuesday 19th August 15:02

[Neil_Sc]

B16 RTT said:

Plasterboard would be fine provided you use this: -



Prime plasterboard
Coat with waterproofer
Tape all corners, joints etc
Coat again
Leave to dry
Tile

Thats the stuff, although I needed more than that kit could provide so bought larger amounts in separation.

[Emsman]

There is another tanking system made by Biscem.

Usually cheaper, and faster drying.

To be fair, its a little on the overkill side of things for most domestic applications though- none of the major housebulders go to such lenghts on a new build.

Another important thing is when putting a mastic line around baths/showers etc make sure you use silicon and not acrylic mastic.

Also, fill the bath/weight the shower tray when putting it on, and leave it that way overnight.
Fill the bath up, then apply. When you use it, the sealant has dried in waht becomes the expanded position (ie away from the wall) so wont fail down the line

[Neil_Sc]

Emsman said:

To be fair, its a little on the overkill side of things for most domestic applications though- none of the major housebulders go to such lenghts on a new build.

What prompted me was that the plasterboard around the bath was completely rotten.

This from a building built in 1988, so not all that old.



My experience of the workmanship is pretty damn poor.

I therefore decided that for the sake of a £3k bathroom, I'd rather spend the £100 on the tanking solution, than have it rot.

This is just to show the tiles going onto the tanking solution which is on top of Knauf Aquapanel.

[Emsman]

I dont want to sound like an ar*e here, but you would be better off fitting the lip of the bath into the wall.

Ie cut back the plaster a few mm, so the bath fits into the wall. This allows the tile to sit directly onto the bath, allowing the most secure seal. Prior to tiling you can also effectivley 'double seal' by applying a mastic line behind the bath.

Looks like being a good job though, so please dont think i am knocking you, just trying to offer the best advice i can to the original poster.

[Goochie]

I recently tiled the in-laws bathroom and in order to fill a stupidly large gap between the wall and the existing bath, I stuck standard plasterboard to the wall with "no more nails" then tiled on that - without sealing the board (seemed like a good idea at the time).

Its a shower-over-bath so the tiles will get quite wet, quite often.

The tiles have all stuck very well and have been there for months - what is the most likely outcome ?

[Neil_Sc]

Emsman said:

I dont want to sound like an ar*e here, but you would be better off fitting the lip of the bath into the wall.

Ie cut back the plaster a few mm, so the bath fits into the wall. This allows the tile to sit directly onto the bath, allowing the most secure seal. Prior to tiling you can also effectivley 'double seal' by applying a mastic line behind the bath.

Looks like being a good job though, so please dont think i am knocking you, just trying to offer the best advice i can to the original poster.

Your right, might not look it, but the bath is indeed against the wall and the tiles over, these pics are getting on 18 months old now and not had any problems so far, touch wood.

[Neil_Sc]

Goochie said:

I recently tiled the in-laws bathroom and in order to fill a stupidly large gap between the wall and the existing bath, I stuck standard plasterboard to the wall with "no more nails" then tiled on that - without sealing the board (seemed like a good idea at the time).

Its a shower-over-bath so the tiles will get quite wet, quite often.

The tiles have all stuck very well and have been there for months - what is the most likely outcome ?

Would expect the water to penetrate and it eventually rot. The water will go through the grout to the plasterboard