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How to Waterproof a Freestanding Tub in a Shower?

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If you are installing a freestanding bathtub in a shower, it is necessary to waterproof it, and for a plethora of reasons. Waterproofing the tub prolongs its lifespan while it keeps the tub surrounding spick and span.

How to waterproof a freestanding tub in a shower? To waterproof a tub, you need to coat the surface with primer and then install a waterproof membrane around it. After placing the membrane, it is required to coat the surface with waterproofing paint.

How to Waterproof a Freestanding Tub in a Shower

I’ve listed the entire process of waterproofing a freestanding tub below in this article, so follow the steps and do it like a professional. The article even rounds up some mistakes you need to avoid when waterproofing the tub.

How to Waterproof a Freestanding Tub in a Shower: Step-by-step Process

Waterproofing around a freestanding tub in the shower doesn’t require you to call professionals, provided you follow the right steps. I’ve waterproofed my tub, and below I have listed the exact steps you should follow to do it quickly.

Step 1: Prepare the Area

The first step should be gathering all items in one place and preparing the area. Clean the bathtub surrounds, and have the following things handy:

Step 2: Prime the Bathtub’s Surface for Waterproofing

Priming is an essential process to seal around a freestanding bath while it creates a base for the membrane to stick properly. Use a paint brush, and apply generous amounts of primer around the tub surrounds. Make sure the primer penetrates the surface and helps create a good seal.

Note: Wear gloves to ensure the primer doesn’t bounce off on your hands, and you can carry out the process of keeping yourself clean.

Step 3: Carefully apply the Waterproofing Membrane to the Surface

Start with measuring the bathtub’s surrounds using tape. Measure the area you want to waterproof, and note it down somewhere, so that you can cut the reinforcement tape evenly.

Uncoupling Membrane

Once done with the measurements, paint the tub’s frame using waterproofing paint. After applying a thick coat, place the membrane over it, and press it with the brush, so it settles properly in place.

Do this for the entire area that you want to waterproof, and ensure placing the membrane evenly so that it creates a water-tight seal.

Apply another coat of waterproofing paint over the membrane and reinforce the joints.

Step 4: Let it Dry, and Test

Let the membrane and the paint dry for at least 24 hours. Now inspect it by scratching with your fingernail, or you can even splash some water over the seal to check if it prevents the water from seeping inside.

You have now successfully waterproofed the freestanding tub, and it’s ready to use.

Why Should You Waterproof a Freestanding Tub in a Shower?

Is it necessary to waterproof a freestanding tub in a shower? Is waterproofing a tub overhyped? Well, there are multiple benefits of waterproofing around the tub’s frame. Here are a few solid reasons to install a waterproof membrane with your tub:

1. Protects the Tub from Structural Damages

One of the biggest reasons for waterproofing around a tub is to protect it from any structural damage. The hot and cold spray from the shower can lead to damaging the outer area of the tub, and it can only be stopped by waterproofing.

2. Reduces Cleaning and Maintenance

Usually, freestanding tubs do not require a lot of maintenance. But installing the tub in an alcove or near the wall may call for more maintenance and cleaning. Waterproofing reduces the hassles of maintenance, and thus you spend less time cleaning the tub.

3. Prevents Bugs Infestation and Mold Growth

Bugs and mold come attracted to areas where they find moisture. And the surrounds of your bathtub can be a home to such elements if you do not waterproof it.

When installed in a shower, a freestanding tub gets a lot of splashes on it, and there is always some moisture around it. By waterproofing the tub, you can reduce the moisture accumulating around the tub or on the walls, and it helps keep bugs away.

4. It Increases Insulation

The benefits of waterproofing a freestanding tub aren’t just limited to preventing mold growth and protecting the tub’s outer, but it also improves the insulation. Waterproofing the tub properly helps in keeping the water warm for longer, so you can soak and enjoy it for more time.

Mistakes to Avoid When Waterproofing a Freestanding Bathtub

While waterproofing a bath sound like an easy task, there are some tiny mistakes a lot of homeowners make. Avoiding these mistakes will help you do the job quickly.

1. Not Priming the Surface Evenly

Do not take priming for granted, and do it properly. The primer is the base coat, so it should be even while sealing the small area around the bathtub. Apply it in abundance, and make sure the primer does not drop inside the bathtub.

2. Not Covering a Bathtub

Not placing a plastic cover over the bathtub while waterproofing will attract a lot of cleaning. Inevitably, the primer or paint will fall off on the tub, and you may have to clean it right after applying the membrane.

3. Not Measuring the Edges of the Tub Before Applying Waterproofing Membrane

Superhesive Transparent Filament Reinforced Strapping Tape

Always measure the reinforcement tape so that it sticks to the tub properly. Leave 1-2 inches extra tape on both ends, and cut it with scissors after applying the tape.

4. Doing It in a Rush

Rush is your biggest enemy when waterproofing a bathtub in a shower. The process requires a lot of care since you need to create a waterproof seal around the tub. Apply the primer carefully, then wait for some time, and apply the tape.

Moving the paint brush vigorously won’t be useful, and you have to waterproof the tub again.

5. Don’t Use Cheap-quality Materials

Cheap quality materials are inexpensive, but they do not last long, so you have to apply the coat over and over. Always invest in good quality materials such as waterproofing paint, reinforcement tape, and primer. Moreover, ensure the brush has the bristles intact to apply the primer’s coat evenly.


Q1: Can you have a Freestanding Bath in a Shower?

A1: Yes, there are some amazing freestanding tubs for small spaces that you can have in a shower. Just make sure to choose a bathtub that fits perfectly and looks good in the shower area.

If you are not sure about the installation, hire a professional guy that installs the bath for you.

Q2: How can I Waterproof my Bathtub with a Flange?

A2: Some tubs have a flange to keep the excess water runoff correctly in the main drain. If your tub also has it, make a cutout in the membrane tape so that the flange remains functional.

Q3: Can you do your own Waterproofing around a Freestanding Tub?

A3: Yes, you can waterproof a freestanding tub on your own, and there is no need to call professionals for it. Follow the steps listed in this article, and you can easily do it within a few hours.

Q4: Is a Waterproof Membrane Necessary?

A4: A waterproof membrane is absolutely necessary because it helps create a water-tight seal. Measure the membrane properly, and then stick it on the tub’s frame over the primer.

Q5: How many layers of Waterproofing Paint do I need?

A5: I recommend using two layers, as it helps the membrane stick in place while lasting longer. You can even use one layer, as you have already used a layer of primer as a base. But make sure to coat the waterproofing paint evenly to cover the reinforcement tape that helps create a good seal.

Final Thoughts

So, you know everything about how to waterproof a freestanding tub in a shower, and you are all set to do it. Follow all steps in the order they are explained, and make sure the tape sticks properly, especially around the edges.

When priming, ensure the primer does not spill over around the surroundings and use an old sack to cover the nearby walls. Lastly, let the waterproofing paint dry properly before you fill the tub for bathing.


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