Walk-in shower in a prefab house, tiles or shower tray?

I would never have a tiled sink or bathtub made :)

Your loss! ;) Even better would of course be both carved from natural stone. Although I probably wouldn’t get that past my wife either.

Exactly, silicone joints are actually only for looks or to prevent water from standing too long on the floor beneath the objects or tiles. In principle, it shouldn’t matter if sealing slurry, liquid plastic, and tapes as well as collars were used underneath. That’s the only proper way. It does not matter whether it’s timber construction or concrete or whatever... Insofar, you could already claim warranty because that is a defect! The problem, of course, is the interface. A shower tray is usually plumbing work, waterproofing is usually done by the tiler. He might have said to you, well if the shower isn’t tiled, I won’t seal underneath either. But the plumber should have objected. Or did the plumber install the tray before the tiler? Then he would have had to either object or seal it himself...

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Insofar, you could definitely claim warranty because that is a defect! The problem, of course, is the interface. A shower tray is usually plumbing work, sealing is usually done by the tiler. He may have said to you, well, if the shower isn’t tiled, I won’t seal underneath it either. But the plumber should have complained. Or did the plumber install the tray before the tiler? Then he should have either complained or sealed it himself...

Exactly right. Our tiler forgot to seal the fittings in the shower. The glazier (floor-level walk-in all-glass shower) then simply installed it (which he actually shouldn’t have), but by then the damage was already done. Solution (expensive because 4x !!): sealing collar on the mounted glass pane, with another glass pane over it! (The alternative would have been a complete dismantling of all 4 showers with costs of over 10K!)
The invoice went directly to the tiler, so I don’t know how much the fun cost (probably around 2K?). We were, however, "not amused" about the delay since it was almost the last trade. So as a client, always make sure everyone does their job well :rolleyes:

Or did the plumber install the tub before the tiler at your place? Then he would have had to either complain or seal it himself...

Unfortunately yes :( The substrate preparation was done beforehand..., then the plumber installed the shower tray, later it was tiled and unfortunately I was not involved in the matter. It’s a mess and I’m putting it on my list to complain about. I’m already looking forward to the discussions when the time comes :(

Craftsmen, first you can't get hold of them, then they just complain and demand high prices, then they don't deliver as promised, mess things up, try to cover it up and when you have them by the balls using an expert or photos (or both), they say another craftsman or yourself is to blame. There are really only a few exceptions that do a lot right and actually none that do everything right from start to finish. At least I have not experienced any.