View Full Version : No mortar under BainUltra airbath?

12-16-2007, 01:11 PM
I'm a DIYer and have just started a master-bath remodel. I've removed a whirlpool tub that has a capacity of 150 gallons. Now I'm preparing the site for a new BainUltra airbath with a capcity of 65 gallons.

Looking through the instructions for the BainUltra tub (Amma 42"x72" oval), there is no mention of a mortar or adhesive bed under the tub. Normally, I'd just go ahead and put some down, but the whirlpool that I removed didn't have any mortar under it.

The new tub is installed in a podium with a surround, just like the old tub. So my guess is that I don't NEED to put mortar underneath, but I don't know how to verify.

Any ideas? Is a mortar bed necessary for a podium-style tub and surround?



12-17-2007, 05:31 PM
Go to their web site and click the contact us and ask or call their 800 number. Most new tubs have OSB built into the fiberglass or whatever they are made out of and they have feet that need shimmed with some thing, but not a full mortar bed like the old ones. If in doubt ask the manufacturer.

12-17-2007, 06:51 PM
focus on the feet. Don't mention the podium or else people will have to step in and tell you that it is not relevant to the support under the center of the tub.


12-18-2007, 11:15 AM
I gave BainUltra a call and they verified that the cement underneath is not necessary. Of course, they said I can used it for added stability if I would like, but that it is not necessary.

I'll take a look under the tub (which I haven't done yet) to see if there are any feet. When I do the dry-fit, I'll see if it seems stable enough.

12-18-2007, 03:37 PM
Nearly any non-cast iron tub will feel more substantial embedded. A few inclue a full-contact support.

master plumber mark
12-18-2007, 04:20 PM
why dont you just spend the extra
5 bucks for 2 bags of sand mix and be done with it???

you cant hurt it....
and it can only help down the road

especially if your wife packs on an extra 150 lbs someday.....