New shower, old tiles.

[Unregistered]

Hi.
I am a DIY'er looking for a bit of advice. I am fitting a bath tap/shower mixer in a room that has not previously had a shower. There is existing tiling in the bathroom from floor to dado height including approximately 2ft above the bath and there is a Silicon sealant join. I am obviously going to have to tile above this level for the shower but my first question is whether this old tiling, having never been intended for use in a shower area, is likely to be OK in its current form. I think I have three options:
1. Leave current tiling over bath and just tile above that.
2. Attempt to improve(?!) current tiling (Fila fugaproof?) and tile above.
3. Remove current tiling above bath and re-tile bath to ceiling.
The existing tiling is dark green which I would not be able to (or want to) match so I will use a plain white or cream tile. Not only would leaving the existing tiling in place be less work but I think it would also look better. So....
Are old tiles and whatever adhesive and grout was used likely to be suitable for use in a shower area?
If this is unlikely is there any point in using a grout sealer or is this just a bodge?
The walls are painted plasterboard. If I first sand down what would you recommend for primer, adhesive and grout (I will be using cheapish ceramic tiles)?
If I have to go to the trouble of replacing the old tiles would you recommend tanking?
What is the best way to join tiles to bath?
Massive thanks in advance to anyone who can help. I have tiled a bathroom in a previous house and quite enjoyed it but have to admit I did not think of these questions back then and would like to make sure I am doing things right this time around .

 

[judge]

The correct and neatest job your gonna get is to remove the old tiles from wall,remove the existing plasterboard and replace with either water resistant plasterboard or cement backerboard,tank area with a tanking kit and install tiles.-(use good quality Silicon in all corners and fill bath before siliconing .)

 

[Unregistered]

The correct and neatest job your gonna get is to remove the old tiles from wall,remove the existing plasterboard and replace with either water resistant plasterboard or cement backerboard,tank area with a tanking kit and install tiles.-(use good quality Silicon in all corners and fill bath before siliconing .)

Thanks Judge. I appreciate that would be gold standard but I'm afraid it would be too much of a project just now. The bathroom will probably be redone in a few years when money allows but I need the shower sooner for the kids and occasional visitor. It is a low pressure gravity system that will only be used occasionally - but I still obviously need the tiles to do their job! If gold standard isn't possible then what might be the minimum for these circumstances?

Many thanks.

 

[Unregistered]

Hi, does anyone else have an opinion on this or is the consensus that I need to strip out and replace the plasterboard? Also, out of interest why is backerboard required as well as tanking - surely if the tanking works then this would not be necessary?
As much as I would like to do things belts and braces I am not sure I understand why this is required. If a little old state pensioner got you in to do this job for an occasionally used shower would you really all insist on stripping everything back to the stud work or not at all?

Another reason that that this is not a good option for me is I know that the ceiling has asbestos artex - so removing the walls and inevitably disrupting the ceiling is not an option. So I need to be pragmatic.

Thanks in advance. I do appreciate all advice.

 

[DHTiling]

Hi.. Sorry but we do not recommend trying to bonny the dog... it is your choice if you want to do said project that way..

Good luck either way..

 

[gamma38]

Hi, does anyone else have an opinion on this or is the consensus that I need to strip out and replace the plasterboard? Also, out of interest why is backerboard required as well as tanking - surely if the tanking works then this would not be necessary?
As much as I would like to do things belts and braces I am not sure I understand why this is required. If a little old state pensioner got you in to do this job for an occasionally used shower would you really all insist on stripping everything back to the stud work or not at all?

Another reason that that this is not a good option for me is I know that the ceiling has asbestos artex - so removing the walls and inevitably disrupting the ceiling is not an option. So I need to be pragmatic.

Thanks in advance. I do appreciate all advice.

Sure if a little old pensioner got me into his or her house to do some tiling i would just throw some tiles up and do a runner, would you like someone to do that to you only to have the tiles fall off two weeks later??? If you can't afford to do it properly at this stage keep having occasional baths and wait until you can afford to do it properly.

 

[Unregistered]

OK, so.... do it properly or not at all. However, I still don't understand why replacing the wall is necessary as well as tanking and I would be very grateful if somebody could explain this. Quoting from the leaflet for Mapei Tanking Kit:

"WHERE TO USE
Waterproofing indoor floor and wall surfaces that are not subject to rising damp.
Flexible, anti-fracture membrane. Apply before the installation of ceramic tiles or stone material.
Mapegum WPS may be used on the following:
• plasterboard, gypsum or cementitious render,
lightweight cement block and marine-plywood;
• cementitious, anhydrite, wooden and magnesite substrates and existing ceramic and natural
stone after the application of Mapeprim SP primer."

....So according to the manufacturer this product is for waterproofing and is suitable for use on plaster. Is there something that I am missing or misinterpreting?

Many thanks.

 

[JJS1410]

As people who do this full time the recommendation to remove all tiles, tank etc stands.
However with budget constraints you can pick and choose from the following:
1. If NOT removing the existing tiles, tanking above these will be pointless as the main water penetration will be at the lower/existing level which with no other information we have to assume is not tanked.
2. The recommendation to plasterboard once the tiles have been removed is to give you and even and sound substrate on which to tile, and when tiling onto plaster/plasterboard in a shower area you tank - full stop! Use of the backer board would be the way we would do it, along with tanking.
I do agree with the previous recommendations for you, but it is your choice with all your considerations and the above advice taken into account.
If you have any other questions, just post them.

 

[SJPurdy]

No you are not missing something.
if building from new I would always recommend using a waterproof tile backer board correctly fitted and sealed.
However, if, as you do, there are existing sound walls then these kits are designed to put a waterproof coating on top of the water sensitive wall substrate so that any water that permeates through the grout can not reach the sensitive wall and cause damage. you are doing right by sanding away the paint first before applying the tanking kit. Follow the kits instructions as to corner tapes, priming and number and thickness of coats.

 

[Unregistered]

OK, thanks for clarifying. I have 1 more question! If I make good and prep the existing wall for tanking what would I use to seal the gap between the bath top and tanked wall? As far as I understand the waterproofing tape in the likes of the Mapei kit is for joints between two tanked substrates such as wall-to-floor, not wall-to-bath. Would I use an acrylic or Silicon sealant (eg. Mapesil AC)? I am presuming this would be a necessary step or moisture permeating the tiled surface could make its way down the tanking and wet the portion of un-tanked wall behind the bath? After tiling, the bath top would then be sealed with Silicon on top of this?
Many thanks.