Planning to have an indoor hot tub? These are some things to bear in mind

4 issues that apply to indoor hot tubs.

We usually think of hot tubs and spas as being an outdoor experience but there are many people who prefer their hot tub to be inside.

There are some obvious advantages to this; you can be assured of your privacy, you are completely unaffected by the weather and, if you have an indoor pool, then a hot tub alongside it makes a delightful spa complex.

However, there are things you should be aware of when planning an indoor hot tub installation.

Damp, mold and mildew.

The water in a hot tub is kept at a warmer temperature than in a swimming pool, which means that it evaporates more readily. Aside from the temperature, the jets and bubbles also tend to increase the amount of evaporation that is occurring.

The warmth of the hot tub water also encourages bacteria to grow and, although chemical treatments in the spa water should keep these in check, once the water is outside the spa due to evaporation, splashing or dripping from bathers as they get out, the traces of bacteria can multiply and produce mold and mildew.

So always try to keep the areas around your hot tub wiped down and dry.

Ventilation issues.

Another common problem is the lack of proper ventilation for your indoor hot tub.

As we have already pointed out, a lot of steam rises from the hot tub and if the indoor space is not adequately ventilated, that moisture will form condensation on windows and walls and possibly collect in hard to reach places where, once again, mold and mildew can become an issue.

Your local Sundance dealer will be able to give some recommendation about just how much ventilation you need for the space that you are using.

Slippery floors.

When a hot tub is outside, the area around it is very often covered in decking or non-slip exterior tiles.

It’s also probably true that water evaporates off the area that surrounds your hot tub more quickly outside.

With an indoor spa or hot tub, standing water on and around the hot tub is a slipping hazard. Indoor hot tubs are often surrounded with decorative tile or other flooring and, in order to prevent accidents, the water on the floor around the tub needs to be soaked up often, preferably after every use.

The last thing you want to do is to relax in your hot tub and then slip on the floor after you get out.

You should also ensure that the room that you are planning on putting your hot tub in has enough headroom so that you will be able to step up and out of the spa safely.


Aside from the bather’s comfort, installing your hot tub in a poorly insulated room brings us back to our old problem of condensation.

When warm, moist air from the hot tub meets cold windows, doors and walls you get condensation that can start problems with damp, mold and mildew.

The walls should be well insulated and double-glazing is recommended. Doors and door surrounds are always an issue and you might need to seek specialist advice on this.

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