expanding foam under shower tray

smpillai11

I am getting a new stone resin shower tray installed in my bathroom. One of the guys who gave quotes for the work said that he would be using expanding foam under the tray. Is this recommended? Will the foam not compress over time?

Outkast_IRE

smpillai11 wrote: »

I am getting a new stone resin shower tray installed in my bathroom. One of the guys who gave quotes for the work said that he would be using expanding foam under the tray. Is this recommended? Will the foam not compress over time?

No i have never heard of this method surely the expanding foam would have the potential to push the tray off level as it expands !!!
And as you said it would compress over time etc.

The usual method it to sit the tray in the final postion and check the levels , where its high and low etc.
Personally i used to use flattened copper to increase the height in the needed areas . i trusted the flattened copper as its a metal and had already been hammerd flat with a lot of force.

Once your happy with the levels that fine but you need something to act as a solid leveler under the tray, i have seen things used like very fine sand and cement, skimcoat or bonding mixed and used, these would be fine as they set solid without expansion etc.

corkgsxr

seen it before. didnt like it. youv no way of keeping it level. and unless its well braced itll slide off the base.

plaster or cement.

or you could be surprised and it might be level. happened me once

smpillai11

Outkast_IRE wrote: »

No i have never heard of this method surely the expanding foam would have the potential to push the tray off level as it expands !!!
And as you said it would compress over time etc.

The usual method it to sit the tray in the final postion and check the levels , where its high and low etc.
Personally i used to use flattened copper to increase the height in the needed areas . i trusted the flattened copper as its a metal and had already been hammerd flat with a lot of force.

Once your happy with the levels that fine but you need something to act as a solid leveler under the tray, i have seen things used like very fine sand and cement, skimcoat or bonding mixed and used, these would be fine as they set solid without expansion etc.

Yes, thought the same. I will ask him if he can use cement sand mix instead. Thanks for your thoughts

Outkast_IRE

corkgsxr wrote: »

or you could be surprised and it might be level. happened me once

Same here, i ended up borrowing somone elses level too because i didnt believe it

corkgsxr

Outkast_IRE wrote: »

Same here, i ended up borrowing somone elses level too because i didnt believe it

youd be hit in the head with a gold brick out of the sky faster ffs

Dtp79

smpillai11 wrote: »

I am getting a new stone resin shower tray installed in my bathroom. One of the guys who gave quotes for the work said that he would be using expanding foam under the tray. Is this recommended? Will the foam not compress over time?

Make sure that cowboy dosent use foam under the tray. I've even heard of lads using silicone. Trays MUST be fully supported under the entire base. I prefer bonding myself. Put plenty of blobs on the ground where the tray is going. Place the tray down and press on it. The bonding will spread and the blobs will meet forming a completely supported base. 15-20 mins later the bonding is set almost. I usually leave the tray 12mm off the floor so the tiles can slide in past the edge of the tray. You'll know it's done right if you knock on the tray all over the base the next day. You should hear a solid sound. Any hollow noises mean the bonding didn't spread to that area. Insist on this

TPM

Check the installation instructions for the tray. some manufacturers require a sand/cement screed. If its not done right the first time its a hell of a job to rip it and the tiles out to try redo it.

Dtp79

TPM wrote: »

Check the installation instructions for the tray. some manufacturers require a sand/cement screed. If its not done right the first time its a hell of a job to rip it and the tiles out to try redo it.

Yes that's true. I forgot to mention the Sand/cement. I often use that but I generally prefer bonding. Either is fine I'd say

martin46585

Is this gentleman trying to retro fit the tray, and in doing so trying to 'seal' the tray against the wall seal, by sliding in the tray, and then apply the foam.
Just thought I would ask as back in the good old days, i had a similar genius suggested such a task when the tray had to be replaced.

Does your man own a horse as well, mind did......

Joey the lips

Don't know why he is bothering with foam it's just to risky. Most builders in the boom did not use anything but each to there own. Personally I would just use tile adhesive or sand and cement .