Unless you re installing a cast iron bathtub you are going to need a mortar bed to support your tub base.
Mortar for bathtub.
Unsupported fiberglass and acrylic tubs tend to flex under the weight of water plus bathers which can be bad news in terms of your drain staying connected and the tub base remaining solid and free of cracks.
Mix the mortar so that it can support the tub.
Pour the mortar on the subfloor so that it s a few inches from the drain opening.
Both regular thinset mortar and floor leveling compound are suitable.
It is applied to the substrate with a notched trowel.
Setting tubs in mortar is a method used by professional plumbers who specialize in quality home construction.
The mortar conforms to the contours of the tub and when it sets it prevents the tub from moving and supports the weight.
The mortar provides a stable base for the tub to rest on when the tub is full so the casing of the tub doesn t have to support all of the weight and crack.
Here s another one of th.
Thinset tile mortar has a smooth slippery consistency similar to mud.
Then embed the tub into the mortar.
Thinset mortar is your default tile mortar for most indoor and outdoor applications.
It should not be runny but rather stand up on it s own.
The mortar provides a stable base for the tub to rest on when the tub is full.
The mortar should be evened out and about 2 inches thick on all sides.