Tiling onto plywood

You don't want to use epoxy anyway

Oh and the tiled ceiling warning was more incase they fell on your head

What did you use to stick them?

Plywood expands and contracts more than concrete backer board. If water finds its way onto and into your plywood, the plywood will expand. The expansion will create a soft spot under the tile that will give in when someone steps on it. This will almost always cause cracks in your grout and in some cases will pop tiles up completely.

hello
I have a sample too, this floor was done half year ago in steam room, Ply was tanked with paint on system all joints seems was taped too,
Ply was soaking wet, I was ripping ply like piece of paper, just pure nightmare

I thought people might be interested in an update. The shower I described earlier has now been in daily use for almost two years and seems to be fine. No leaks, no signs of cracking and even the tiles on the ceiling are still stuck solid. Time will tell of course, so fingers crossed for the next 10 years. I took this photo this morning:



Sorry about the orientation - couldn't seem to rotate it, or delete the second attempt!

Whoosh - another 10 years gone by!

Someone might be interested in another update so here are a couple of photos I've just taken of the shower cubicle in question.

12 years of almost daily use since it was finished there have been no leaks, no cracks, no tiles have dropped off, in fact no problems at all except a bit of discolouration of the grout.

Not bad for a DIY job, considering most of the advice was to use cheaper and faster materials. I understand this because professionals are always under price and time pressure, but at the risk of being controversial I'd suggest that most DIYers are capable of as good if not better results than most professionals, as long as they take their time.

In my case, I spent a ludicrously long time to build this shower cubicle (in fact, it was a completely new room), which would never have been acceptable to any professional's customers. Also, because I was saving loads by not having to pay someone, the materials costs were not as important as they would be for a professional. So when I built the stud wall to create this shower room I used treated 4x2 C24 structural studs instead of the more 'normal' 3x2 carcassing timber, plus I spaced them closer than 'normal' for extra strength. Basically, I over-engineered the whole job but the extra cost of the materials was probably only a few £100 (this was 12 years ago!).

So it's an interesting dilemma. Pay a professional for a fast job or DIY and save a lot of money? The big factor, of course, is time and the fact that I have plenty of it, being retired. But when the job is finished, only the end result is important because no one ever asks 'how long did that take?' and it's only the final quality that matters.

The tiling industry does not endorse the use of marine ply in showers, bathrooms, floors let alone wetrooms. From a tiler's point of view, it is incorrect to do so. The use of plywood is a commune practice and a huge error within the building industry. A real shower/wetroom should last a lifetime with proper maintenance/mold free.

Out of interest, what would be considered a 'lifetime'? 25 years? 50 years?

Also, if it's a 'common practice' and a 'huge error' then it suggest the building industry has a serious quality problem.

As for mould-free, I'd suggest that's more to do with adequate ventilation - something the building industry also seems to forget in it's pursuit of energy-efficient, insulated-to-within-an-inch-of-its-life, houses. Certainly nothing to do with a bit of plywood instead of tile-backer. Fortunately, I have plenty of ventilation and have no sign of mould.

My only complaint is the mild discolouration of the grout, which seems to be commonplace in shower cubicles if one of my other professionally installed shower cubicles (using tile-backer board I hasten to add ) is anything to go by. Perhaps I should have used epoxy grout?

Having said that, my latest (professionally installed) bathroom has a corner shower faced with just two shower panels, so no need for any grouting. I wonder how long it will be before tiles become regarded as a 'huge error' for shower cubicles?

Great to read and see your own project.
The advice given back in 2012 and onwards ref tiling onto plywood was through experience from a professional viewpoint. Reading the British Standards for internal tiling it has been updated over the years to now being classed as unacceptable. From my understanding it’s due to the poor quality of plywood being imported.
Looking at your early pictures I can see that your shower only has full sheets and with only corner joins movement will be minimum.
My own shower of 25+ years is of plywood construction on 1 stud wall, however now all areas of moisture require fully waterproof substrate.
As we work in a fashion industry I’d expect new designs to reduce the longevity of tiling to around 8 years!
IMHO.

Glad to hear that your plywood shower has been good for 25+ years.

Btw, I'm not trying to advocate plywood over other alternatives and doubt I would use it again for a shower cubicle. My point is that it CAN be used effectively with appropriate design (as you have noted), even though it may not be the 'British Standard' way of doing so.

It's interesting that you mention "all areas of moisture require fully waterproof substrate". On the face of it, this seems like good sense, but like most things the devil is in the detail. Tiles are waterproof, as is their adhesive layer, so 10 minutes of splashy water shouldn't be a problem, but we tank a plywood substrate anyway for 'belt and braces' - design redundancy, if you like. Inherently waterproof tilebacker board doesn't require tanking, making the job easier and quicker, so arguably a better solution - arguably because while it is easier and quicker to build, the end result (ie functionality) is the same.

But if tiles or shower panels themselves are waterproof yet the 'standards' still require a waterproof substrate, why stop there? How long will it be before the 'standards' declare that a stud wall is unacceptable and that only brick or block walls should be used?

Having said all that, your point about all this being part of a 'fashion industry' probably trumps all other considerations as houses up and down the country have their perfectly functional bathrooms (and kitchens) ripped out and replaced with something more 'up to date'. I suppose it keeps the wheels of industry moving.

The grout discoloration you are talking about is in fact mold, you follow the silicon that goes up the corner wall and you will run into black mold, also follow the silicone at the bottom corners, that's black mold as well. It is a worn-out shower.

I appreciate the waterproofing that you did, most builders don't even think about that one. You get credit for that!

Using epoxy grout is not the answer. Due to loads of condensation A shower needs to breath to stay dry. Epoxy grout does not provide that. Powder grout is breathable and allows the shower to dry up daily. All it needs is maintenance. Same thing goes for panels.

Shower panels have their ups and downs. The way they look, color fades, scratches, the silicone bead catches mold just like any other shower etc. It is not appealable to most human beings. It looks good if you don't use it.

Interesting comments about epoxy vs powder grout, though I'm not really understanding why a breathable grout helps a shower to dry out after use. I'd have thought a breathable grout would retain moisture and therefore take longer to dry completely, hence promoting mould growth. After all, the tiles themselves don't seem to attract mould and they get just as wet as the grout, but they also dry faster because they are impermeable so can't retain any moisture. I imagine that epoxy grout would perform in a similar manner to the tiles, ie present an impermeable surface to the water that would be easier than grout to wipe clean. Also, any mould that did form would not, I assume, be able to 'inflitrate' the structure of the epoxy grount, in the same way that it cannot infiltrate the structure of a ceramic tile, hence being easy to clean off.

As for shower panels vs tiles, I'll have to wait another 10 years to see how that works out

The idea is the tiles are aesthetics only. Water can ingress through the grout after prolonged use over several days and that water needs breath back out from behind the grout. That's with cement grout mind.

Welcome back matey. Been a while.

Tiles falling off the wall due to condensation: shower head
No matter what you install on the walls, tile or panels there is ongoing condensation going on behind the tile/panel 24/7