Shower sealant not lasting

[FSVin]

I have an upstairs flat with a bathroom extension out the back, through a galley kitchen. My downstairs neighbour keeps getting rained on. The only issue seems to be the sealant around the shower tray, which gradually pulls away, presumably owing to springy floorboards under the tray. I've been redoing it every 8 months or so, although sometimes this still isn't often enough to prevent the beginnings of the drip depending on how good a job I did to begin with. It's embarrassing getting a knock or a text because the stuff in her cupboard is wet again

Is there any better solution to this? It's a horrible, time consuming job, scraping it all off and starting over again as often as this. Should I just be using a grossly excessive amount of sealant so it lasts longer? And does that frequency ring alarm bells to anybody, suggesting there's something else that needs addressing, or is that just how often showers on springy floorboards need resealing? I'm slightly concerned about the floorboards/joists underneath getting and staying wet too long.

Thanks!

if the "floorboards" are springy they may have been damaged by damp, or the tray might be standing on legs, or the joists might have been weakened by cutting to run pipes .

Have a look at the floor. You may have to lift the floor covering at the edge next to the shower. is it chipboard? brown or green? Are there water stains and woodlice?

I think you are going to have to have the tray lifted, the floor repaired, and the tiling redone. The tray should not be moving and the floor should not be sagging.

You might bodge for a while with a sealing strip that has a silicone rubber seal fin, but the better ones are fitted before the tiling.

Thank you PigletJohn. I'm keen to avoid lifting the floor to have a look around because it's vinyl tiles that have been glued together, so I'm not sure how to take any of them up without ending up having to redo the floor (which runs through the kitchen too). I have seen the odd woodlouse around, but discovered a few months ago that the stud partition wall that forms one side of the shower was bodged at the bottom, where the two perpendicular sealing strips didn't meet, and the gap was just filled in with loads of silicone. Water had been getting behind it and rotted the stud, which I think drew the woodlice.

Doesn't sound good, does it? I've been putting off getting anyone in to have a look since my pandemic income is nada and nil.

the longer you leave it, the worse it will get.

Woodlice lay their eggs in water, and feed on the fungus that grows on rotting wood.