Im installing on the second floor a new air jet acrylic tub and was prepared to set it in mortar until I noticed there are 4 acrylic legs molded under the tub that are aprox. 6 inches high. Install instructions make no mention of a mortar base and state for an alcove install to shim the legs to level and put up 3 edge supports, also putting a support in the front of the tub. Im just wondering that since this tub is off the floor by quite a bit I would need a signifigant amount of mortar. Would I be better off using low expansion foam or do I need anything at all. The installers told me they dont use anything under them but who knows how long these tubs have come with built in leg supports. Sorry Im at work right now and cant remember the name of the manufacturer of the tub.

We bought our first house last summer and have now realized that the bathtub in the basement is unlevel- left to right. This causes the water to run over the sides of the tub when the shower is in use. The house was built in the 70's and i believe this is the original tub. Although the inspector thought the water was due to a leaky toilet bowl ring it is now apparent to us that this problem has been going on for a long time and we won't be the first ones to try to fix it. Can anyone tell me what fixing an unlevel bathtub would entail? Do we need to replace the tub with a new one or adjust the tub that is in place? The tub has a tile surround, it's set on concrete and there is vinyl flooring. Any advice would be appreciated!