Why Is Mortar Used Underneath Bathtubs? What Are The Risks Of Not Using Mortar Under The Bathtub? Its Often Best To Use Mortar For Your Bathtub Installation Can a bathtub be installed without mortar? Although it is feasible to build a bathtub without using cement, depending on the kind of bathtub, it might not be advised.

Would you be better off asking: Should you? Mortar is frequently a crucial component of the procedure.
Typically, mortar is used to stabilize the tub and prevent movement.
There should be a manual included with your bathtub model that contains detailed installation instructions.

What is the manual’s position on supports? Does your bathtub have normal feet or fancy ones? Does the bottom flex at all? Whether or whether you require mortar will depend on information about your tub.


When a bathtub is exceptionally hefty or holding a significant amount of weight, mortar is frequently employed. Even though not all bathtub models require mortar, it can be a crucial tool for leveling and anchoring your tub.

You can alter your tubs’ level by pressing them deeper into the bed of fresh mortar. This enables you to precisely angle the model for best drainage.

The tub’s corners are fixed into place once the mortar hardens. You will have support while sitting inside the tub, and it won’t move when you change your weight.

This support can enhance insulation and stop the tub’s floor from stretching, which causes it to deform downward.

Another crucial point is that a mortar bed can aid in damage prevention. If the fiberglass or vinyl used to construct your bathtub is old, it may crack and dry out.

They become harmed after years of stress from the weight. Stabilizing mortar’s support aids in preventing this.

If you’re doing your bathtub yourself, you might want to forgo the mortar bed because it’s not usually simple to lay. In fact, your plumber may have mentioned that they don’t like mortar beds.

However, adequate bathtub stabilization will provide significant advantages in the long run.

WHAT DANGERS ARE THERE IF MORTAR IS NOT USED UNDER THE BATHTUB? When you install something without using mortar, you run a number of possible risks. You must reduce these dangers and confirm the safety of the tub in the owner’s manual.

Some of the most pressing issues are as follows:

The bathtub can shift when you move because it won’t be securely fastened in place. Without support, the tub’s bottom will flex, warping and bending. If you use shims in place of mortar for leveling, you can avoid the tub from being fitted level. Due of the added strain, materials like fiberglass and vinyl will start to degrade in around ten years. The dampness or the weight of the feet will harm the floor beneath the tub. Basically, you should follow this important step if you want extra solidity and longevity. Failure to do so could result in damage to your floor or bathtub.

If a tub is small, you might stabilize it using different methods. Some people, for instance, employ plaster or wood paneling.

However, these materials must be precisely trimmed to the tub’s shape. On the other hand, until it dries, mortar can be worked into the ideal shape.

It is frequently best to use mortar while installing a bathtub. You likely want things to be as simple as possible when installing a bathtub yourself. You could question whether concrete and cement are the best materials for your bathtub.

In the end, mortar is crucial to the installation process.

Installation instructions should be in your tub’s owner’s handbook. Is it instructed to place the tub in mortar? If so, you ought to adhere to those instructions.

Remember that a mortar bed might hide a tub’s legs. You might need to find a unique solution if your tub has decorative legs.
In some circumstances, a tub may not require mortar support. It is usually not necessary for highly stiff tubs or tubs fixed on the floor.
Instead of mortar, you might potentially utilize materials like gypsum plaster.





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