Tiling letting water through even with Membrane

17 Mar 2019
Reaction score
United Kingdom
Bear with me, this is a long story:

This the 5th time I've had this work done, and no body seems to know the cause. I have a bath mounted shower, which comes off a bath mixer tap which come from the floor. (THERES NO PIPES IN THE WALL). This was all originally fitted with new tiles after I moved in about 6 years ago...since then I've had to get it redone 5 times, and the same thing happens.

The tiles are letting water through or moisture is building up between the tiles and the wall. I know this has happened as the wall shows damage of the side of the tiling where it meets the non tiled wall. There's no plumbing behind the tiles, the outside has been checked, and there’s no leaks above, and it's a tap mounted shower.

With the first 4 times, the wall wasn’t tanked. Tiles were fitted directly to the plastered wall. Months after tiling, I can pull the tiles off by hand and the adhesive is still completely wet. The wall behind the tiles is all completely wet too. There’s no plumbing in the wall, and it’s not coming from the outside. I’ve had the wall checked for damp. There’s a folding out shower curtain which also isn’t letting water through. Once the tiles are off, the wall drys out within just a couple of days.

It’s a ground floor, exterior wall, brick and plastered. I have noticed that all of the previous tilers have just tiled straight onto the plastered wall, no waterproofing or aqua board, just tiles straight into the wall.

No body seemed to know the cause. I’ve had 4 different tilers, retile it and get the same result.

The tiles and grout look perfectly fine but the wall is soaking underneath and the tiles Just pull off.

Anyway, a year ago, I let the wall fully dry out again with no tiles on, and I finally had a proper job done. Different tiles, and the wall was fully tanked with sheet membrane (not a paint on one).

A year on, and it’s happening again. I don’t how this is physically possible with a membrane liner on the wall.

Please see pictures. I’ve included a photo of the original problem before tanking and now.

The original problem:

Tanked with membrane and retiled:

Now, a year later:


Sponsored Links
Looks like shower screen? (Or whatever that is) may not be correctly sealed at tile edge ?
Ground floor external wall. Screams penetrating or rising damp to me. How are things outside ? - broken drain ?, leaking pipe ?
I’ve had it checked or damp. No pipes either. Also, when I’ve had tiles removed previously, the wall dries out in a day or two, and stays dry, even in bad weather.
Sponsored Links
I’ve had it checked or damp. No pipes either. Also, when I’ve had tiles removed previously, the wall dries out in a day or two, and stays dry, even in bad weather.

Well the damp is coming from somewhere and if it is not from the bathroom side then it must be from outside. Damp will dry out when exposed to the air but will increase greatly when covered up - by tiles for example. I had a damp floor in my kitchen underneath the quarry tiles after I pulled them up, it however did dry out in a couple of days when exposed to the air.
maybe your plaster is susceptible to damp.

certainly bonding with multifinish 2 coat plasters soak up water very easily.

the first pic may indicate water sitting on the bath edge and soaking into the plaster.

the later damage may be simply water splashing over the shower screen door / metal wall stop and running down.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local