New acrylic tub squeaking and creaking!

[Christian Hedger]

Hello, our contractor just installed new acrylic tubs. I stepped into it for the first time and it squeaks and creaks. I thought this seemed odd. Since the bathroom is next to the an unfinished basement I can look under the tub. When I looked I could see the tub is floating about an inch or two above the ground with just the cement floor below it. After finding and reading the instructions and other DIY instructions it seems normal to install a mortar base. Since this was not done is it even possible to fix this without taking it all out. Like could we put closed cell foam for support? Not really sure how to handle this any suggestions will help.

 

[WorthFlorida]

Spray foam will probably work if you can reach toward the rear of the tub. Use a spray foam for windows and doors or ones rated up to 1" gaps. This type has minimal expansion so as not to push up on the tub too much and putting stress on the acrylic. I've never tried this before, maybe other can give better advice.

 

[Sponsor]

 

[Reach4]

You could stuff maybe golf ball to tennis ball sized (appropriate to the space-- big enough to squish, small enough to insert with moderate force) lumps of mortar in sandwich bags under the tub. I am thinking maybe 40 or so. The plastic bags would keep the mortar from drying out before it hardens.

Would the foam be too soft to help enough? Would the foam expand too much and apply too much pressure? Foams vary.

I am not a pro and I have no relevant experience.

 

[WorthFlorida]

Bags of mortar is not a bad idea. Far better than ripping out the tub.