fiberglass shower pan installation

Have a new house built on a concrete slab.
Shower pan flexes up and down when stepped on. Installer says
it is supposed to flex. But they opened the side
of my house and sprayed in some foam insulation.
This made the outer perimeter firm but the pan still
flexes in an area about 10 inches from the center.
Should I persist and have the pan re-installed or is
what the installer telling me correct?

There is no reason why a properly installed shower pan would flex. To accomplish that, it is often set in mortar. This will extend the life of the thing considerably. Flexing fiberglass will create stress fractures and crazing which will shorten its life considerably. If they had been able to inject a high density closed cell foam all the way to the drain line, it might have helped, but is sounds like they didn't get it in far enough. It will now be a major pain to get off and do right.

i concur

they have to drill deep holes in that foam and spray more in deeper. This takes a foam spray tool to do that; you cannot just spray from a can that any DIY can get at any store.

if that doesn't really solidify your pan, you are in for a lot more trouble.

They sound like lazy lying guys. Good luck.

david

Thanks for the reply. I'm a rookie but I didn't fall off the
back of the turnip wagon last night--that's what they think.
I figured that constant stress on a particluar place on the pan
wasn't good, but they almost had me convinced that it was o.k.
Further suggestions as to what I should say to them would be
much appreciated. By the way I am 72 years old and get the
feeling that they are just trying to blow me off.


Joe McGrail

Don't use foam, it will compress and not do the job. Use mortar. Just put several piles around the area. You will want some space to allow for the excess to squish out. It won't matter if there are areas under the pan that are voids, you will have most of it supported and that will be enough. You're probably getting advice from salesmen at a box store, and they often don't have a clue.