Fix that leak! (Persimmon quality review?)

For the last few years I've scanned the shower tiles every now and then seeking leaks. The grouting would part company from the tiles and I'd patch it up again. We had a plastic shower tray installed from new by Persimmons the builders and it was creaking and moving, causing the leaks. Eventually we had a tiler come in and look at it. Tapping the tiles soon revealed that most of the bottom row weren't in good contact with the plasterboard. We'd found (had recommended) a good plumber and trusted the tiler, so off we went and picked out a new shower, tiles etc. I stripped the old tiles out, revealing little damage, but also very little tile adhesive. They'd hacked the plasterboard away at the bottom to leave room for the tray (it sat some 10 mm bigger than the plasterboard space)! The plumber made up the space with new plasterboard, backed with expanding foam filler. The tiler has just finished - despite having his first sicky in 30 years! Some record IMHO. Minor niggle left, the washbasin is tight up to a tiled area and the new tiles are thicker than the old ones, so we need to wait until the basin is re-installed to cut the tiles. The rest of it looks really good (Thanks Terry).

I phoned the plumber to get tidied up and he (and some of his staff) are down with what sounds like the same dreaded lurgy that had gripped the tiler! I'm hoping they can get back to us within a couple of days, though we're snookered about using the shower anyway. The tile grout indicates it needs two weeks to dry properly, so it's no hurry really.