Just finished tiling our en suite, and – as is the way with amateur DIY – just read threads about waterproofing the substrate etc which I’ve not done, just put tiles up

The previous owner had just put cheapo plastic screens on the walls in the shower enclosure, I thought at the time that he was just doing it cheap and quick. Now I’m thinking that the wall was just drywall and it was a means to avoid tanking it properly

I’m not going to take down the tiles so do you think I can manage by retrofit waterproofing the tiles and grout themselves?

Or otherwise can you reassure me that the walls arent going to crumble away in the next couple of years if moisture gets through?

We had a non-waterproofed tile-on-plaster shower in our downstairs bathroom. Shower itself was fine but the wall in the room on the other side was constantly damp. That was a brick dividing wall so there was a route for the water to travel to the other side. If it’s a stud wall I’d imagine some kind of plaster/wood damage over time.

Not what you want to hear, but there’s a reason waterproofing is a thing.

I tiled straight onto a plasterboard stud wall I built 8 years ago now. No damp has got through at all. You’ll be fine. Redid the grouting a few months back as we wanted to change it to grey grout.

Edit: This is for a bath with a shower as well.

Consider Whiterock or similar for the shower area itself – much easier to clean than tiles.

“Tanking” has become popular because of wetrooms, likewise the use of tile back board becuase it has waterproff propeties. However, as long as you tile and grout well (that includes using the correct grout) and use proper lips on shower trays, there is no reason for damp to appear. I’ve done all 3 showers in my place the old way and they get heavily used with no sign of damp. Just check that any shower fittings are not leaking before you tile and properly fill gaps where pipework comes through.

I had a bit of an argument with the plumber who redid my bathroom over this… I’d read here and on trade forums that it was always advisable to tank a shower or shower over bath (I have the latter) so checked with my plumber to confirm he was intending to do that. His answer was that he never tanks apart from in wet rooms and has never had anyone come back with issues in the 15+ years he’s been doing it.

I asked him to do it anyway (with me paying the extra) which he reluctantly agreed with (after getting his sub-contractor tiler to back him up that it wasn’t needed). The tiler swore blind that grout was waterproof but then also said he’d mixed some stuff in to waterproof it for additional peace of (my) mind. Dunno what it was though and it was mixed into to the wet grout rather than applied after to dry grout.

No clue if it will make a difference in the long but I’m glad I paid the £60 extra for it, that said I have no reason to doubt the plumber’s honesty etc. and he did a good job on the whole (as I said I agreed to pay the extra for the tanking so he had no reason to lie when saying it wasn’t needed).

grout is not waterproof, nor are tiles 100% but in a shower situation they are near enough(does depend on the tile material).

wet areas i always use tilebacker boards or tanking if onto plasterboard because thats how it should be done and i’m getting paid to do it. before tilebacker boards and tanking was common we used to just go straight onto plaster board with no problems and i’ve ripped out plenty of old bathrooms where the plasterboard behind the tiles was solid.

pretty much all the jobs i’ve come accross where plasterboard behind tiles was wet and damaged was due to plumbing leaks, cracked grout or failed silicone so if everything is done correctly and you keep an occasional eye out for grouting and siliconing problems it should be fine.

Excellent, thanks for the help

Plastic screens (wet wall) are in fact the way to go.

No inevitable grout discoloration.
Proprietary angles used at corners designed for the job of keeping water out.
Minimal mastic (mastic/ silicone is always a botch job for keeping water out).
A piece of cake to clean.
Easier to fit.
Quicker to fit.
Waterproof.
Cheaper.

Why people still tile shower/ bath areas is a mystery to me.