Designing Kitchens and Bathrooms - Sterling Vikrell tub trouble

Howdy, I just tore out my old tub & replaced it with a Vikrell tub from Lowe's. The contractor put the tub directly on the slab floor without any mortar or other support. Seemed ok until I used the shower, now I feel the floor of tub flex a little. How bad is this & is there a way to fix it without taking out the tub again ? Thnx

Some manufacturers reinforce fiberglass tubs so that no extra support is needed, sounds like yours is not one of them. It has been a while(years) since I installed a Sterling, but they did not require support then. Apparently they do now, but check their instructions. If the floor flexes, it will eventually crack. Sometimes, spray foam insulation can be added after the fact for support. But if not properly done that can cause problems also.

If the instructions indicate that extra support is needed, the installer should make things right.

Howdy, I just tore out my old tub & replaced it with a Vikrell tub from Lowe's. The contractor put the tub directly on the slab floor without any mortar or other support. Seemed ok until I used the shower, now I feel the floor of tub flex a little. How bad is this & is there a way to fix it without taking out the tub again ? Thnx

I'm in the middle of doing one myself (actually about 3/4 done). The installation and care guide states "verify the bath is level and well supported by the subfloor".

The underside of the tub is ribbed with peglike (about 1/2 inch diameter) supports. I had to build up the subfloor some to make sure mine is "well supported".

Their website is SterlingPlumbing.com. You might be able to print out the install guide from there.

im having the same exact problem. it is flexing because there is not enough support underneath.

i am thinking of getting the foam spray stuff and using it under the tub where it meets the floor.

luckily i still have one wall open on the other side of the tub.