can I tank over old tiles

[henry123]

I now have one wall that is part old ceramic/porcelean tiles and part freshly skimmed plaster.

I am waiting for my Dunlop tanking kit as recommended
http://www.trades-direct.co.uk/modules/ ... e=9005-101

Can I use the kit to tank over both the plaster and lower half of existing tiles?

If not do I need a special primer to put onto the tiles before using the kit?

[RICO]

Hi there,

No you cannot tank over tiles as there is no porous surface for the liquid to soak into.

Why wou need to anyway. If you are worried about water getting thru the existing tiles, do the right thing and get all the old groupt out and re-do it.

Regards
Rico

[henry123]

thanks,

I have chopped off all the old tiles and removed all the blown plaster in the bathroom.

I have re-platsered all the walls and left to dry.

I left one wall which had the orignal tiles half way up but skimmed with plaster above these to make a smooth wall ready for tiling.

I didn't think it through. I knew I was going to tank all the plaster in the immediate bath/shower area but assumed I could tank over the old tiles I left on one wall.

Is there not a primer or something I could coat the tiles so the tanking would stick to it?

Alternatively can I just tank above the tiles and hope the old tiles act as a waterproof layer?

They have been there for 100yrs on cement backing. I am sure they are o.k, I'm just worried about capillary action from them up into the skimmed plaster.

The tiles are in very good condition.

[RICO]

Henry,

Where exactly are the old tiles in releation to the shower/bath

Rico

[henry123]

Hi Rico,

At the tap end of the bath (also the end the shower will fit to the wall).

They cover about 2ft up from the bath across the whole wall, but only the bath width will be exposed to excessive water as a shower curtain will be used, sheilding the rest of the wall.

Above the tiles is newly skimmed plaster flush with the tiles to make one complete smooth surface to tile onto.

Thanks,

Henry

[RICO]

Henry,

OK, as I sad earlier yo can't tank onto tiles and there is NO primer you can use.

Clear out all the old grout from the existing tiles and they grout everything use a water / mold resistant grout. (Get powdered BAL not ready mixed) and all should be OK.

Rico

[bathstyle]

Look into the homelux tanking membrane, this uses tile adhesive to stick on the membrane, Bal WP1 just wont work as suggested.

Use an adhesive suitable for tiling onto ceramic tiles and you should be OK

[henry123]

thanks for the help,

Reading up on the BAL system it mentions you can tank onto ceremaic tiles, but you first need to apply a screed coat of cement based adhesive plus their admix ad1 onto the ceremic tiles.

I guess this will key into the ceremic tiles and then provide something the primer and tanking paint can key into.

What do you think of this and if I do this how thin could I make the screed?

Also can I feather the screed onto the gypsum plaster that has been skimmed?

Although this seems the simplier option it is also expensive, I only need to screed 0.5m2 but the ball stuff would cost a fortune and I'd only need a tiny bit.

(I have already paid for the dunlop kit, dunlop adhesive and dunlop grout.)

[bathstyle]

If it was me, I would spend the £40 and use the homelux kit, it sounds like you're just looking for someone to say that your idea will be fine so you can trot off and do it your way. so, yes, your bodge will be fine

[henry123]

Had a think about this and agree the homelux stuff would be easier and a proper job. Not sure why I didn't come to this conclusion earlier.

where can I get it cheap?

I am just normal person doing some DIY so no trade accounts.

(Yes you are right I was seeking approval for my idea and wanted to trot off happily.)

Many Thanks.

[bathstyle]

Topps do 5m x 1m rolls for £50, £40 trade, just tell them you want to pay £40, things are that bad that they will probably do it.