Shower resealing

The vertical internal corner of a tiled shower takes running water down two planes at once and it is the joint people seal last and worst. It is also the joint that dries slowest, because it never sees moving air.

Sealed properly it wants a slightly fuller bead than the tray run, tooled to a clean hollow so water runs off rather than sitting on a flat shoulder. A corner tooled flat holds a bead of water after every shower, and a joint that is wet for an hour a day is a joint that will grow mould.

A shower screen is sealed on the outside of the profile and left open on the inside. That is deliberate rather than a shortcut. Water that gets behind the profile has to be able to run back into the tray, and sealing both sides traps it in the channel where it sits, smells and eventually finds the floor.

The rubber seals and sweeps on a shower door are parts rather than sealant. They perish, they go brittle and they stop touching the glass, and no amount of silicone fixes that. Where one has gone you get told what it is and where it comes from, rather than having a bead run against it.

A stone resin tray on a solid floor does not move. A plastic tray on a timber floor with no support underneath moves every time somebody stands in it, and that is a joint that will keep failing whatever is put in it.

Where that is what is happening you get told plainly, with what it would take to put right underneath. Hembury Contracting can price that work, and it is a better spend than a fourth bead.

Three different things keep water inside a shower and they get confused constantly. Grout is the hard fill between tiles and it is not flexible. Sealant is the flexible joint where two different materials meet, which is why it goes round a tray and not between tiles. Tanking is a waterproof membrane behind the tiles, put in before any of it, and it is the only one of the three actually holding water back.

So a shower can be leaking through failed grout, through a failed sealant joint, or because there was never any tanking behind the tiles in the first place, and the three look identical from the doorway. A new bead fixes exactly one of them.

What tells them apart is where the water shows up. Damp on the far side of the wall or in a ceiling below usually means water is getting through the wall rather than past a perimeter joint, and no amount of silicone round the tray will change that. Where it looks like that you get told, with what would actually need doing, before any money is taken.