Shower tray flexing

[cf-leeds]

I have a quadrant shower installed in an upstairs bathroom, the shower tray is plastic and in my opinion is not properly installed (not by me I might add). long story - but I'm looking to resolve the problem right now.

The shower tray flexes under my weight and I'm convinced that my foot will go through it sooner or later. The tray has not been bedded into anything, as I believe it should have been.

I don't want to dismantle the shower, if possible as everything is sealed in with silicone.

I'm thinking if squirting some expanding foam under the base, using a long, tube/nozzle. There is a small space round the base where I could do this. After reading in other web sites, I've seen this suggested, though not seen any comments on the result.

Is expanding foam a bad idea ? I know that foam expansion is quite powerful and could possibly push the tray upwards, or even create a bulge.

Should I just bite the bullet and dismantle the whole thing, or even wait for the tray to ultimately break, at which time, I'll be forced to change the tray, maybe for something more solid.

Any tips appreciated.

[John Rumm]

Plastic/glass fibre trays are not usually bedded on, but are supported on a metal framework with feet. They also normally bend a bit under load.

{snip]

First I think you need to get a look under it and work out what type of tray it really is.

[meow2222]

ay is plastic and in my opinion is not properly installed (not by me I migh t add). long story - but I'm looking to resolve the problem right now.

l go through it sooner or later. The tray has not been bedded into anything , as I believe it should have been.

in with silicone.

g, tube/nozzle. There is a small space round the base where I could do this . After reading in other web sites, I've seen this suggested, though not se en any comments on the result.

ul and could possibly push the tray upwards, or even create a bulge.

for the tray to ultimately break, at which time, I'll be forced to change the tray, maybe for something more solid.

Plastic trays do flex, but you're not giving us any clue as to how much.

If the flexing is a problem, injecting expanding foam blind is almost sure to destroy it with huge expansive force.

It might be worth getting access from underneath via the ceiling, if its on a timber framed floor, and putting a run of expanding foam round the outer of the tray, so there's planety of space for downward & sideways expansion , then come back later and do the same again further in, so you build up go od support without destructive forces. Or you could just fit some wood unde r it that the top can sit on. Or you could add fibreglass with lots of rein forcing ribs etc.

NT

[cf-leeds]

tray is plastic and in my opinion is not properly installed (not by me I mi ght add). long story - but I'm looking to resolve the problem right now.

ill go through it sooner or later. The tray has not been bedded into anythi ng, as I believe it should have been.

ed in with silicone.

ong, tube/nozzle. There is a small space round the base where I could do th is. After reading in other web sites, I've seen this suggested, though not seen any comments on the result.

rful and could possibly push the tray upwards, or even create a bulge.

it for the tray to ultimately break, at which time, I'll be forced to chang e the tray, maybe for something more solid.

e to destroy it with huge expansive force.

on a timber framed floor, and putting a run of expanding foam round the out er of the tray, so there's planety of space for downward & sideways expansi on, then come back later and do the same again further in, so you build up good support without destructive forces. Or you could just fit some wood un der it that the top can sit on. Or you could add fibreglass with lots of re inforcing ribs etc.

So I'd say it flexing about 5mm. It also makes a bit of a creek sometimes, while i'm moving around.

The only think I could realistically get under it would be foam, but that s eems quite risky. Maybe there's something else I could inject under there, to add support ?

Thanks for the responses

Chris

[newshound]

I can see that injecting a large amount of foam could be risky, especially if you seal up the hole before it has finished expanding, but I would have thought that a series of sensibly judged "dollops", allowing each to cure before adding another, would be OK. One of the bigger risks, if there is any damp getting down there, is creating perfect conditions for dry rot. You don't want "bulges" which might affect the drainage, but you could put a few bags of sand in there first to bias it concave.

[Andy Burns]

You can get low expansion foams, e.g.

[cf-leeds]

Thanks, I'll look into that one.

Chris

[David.WE.Roberts]

How long has the shower tray been there (roughly)?

We had an old fibreglass tray which had a base of foam with a bit of wood in for 'strength'.

Over time the tray had weakened and water had seeped into the base so the whole thing was slowly disintegrating underneath.

So I don't know if you have a bad install of a recent tray, or an old tray which may be failing.

Cheers

Dave R

[cf-leeds]

This is a relatively recent install and was clearly not done properly.

Chris