Does a Hot Tub Have to Sit on Concrete?

by Michael | Last Updated: April 14, 2021

Deciding on where or what a hot tub will sit on can be confusing especially when you have many options one of which will be putting the hot tub on concrete. But, does a hot tub have to sit on concrete? This is what I found out from having my hot tub moved from my deck to a concrete slab.

A hot tub doesn’t have to be placed on concrete but it’s advisable. A concrete slab is one of the strongest options you can use as the base for your hot tub, so it’s always advised by professionals. However, it isn’t the only base you can use for your hot tub. There are other alternatives to a concrete slab with equal strength.

A concrete slab is usually strengthened by gravel, sand, and cement amongst others. The combination of these materials produces a very strong and fitting base for even the largest hot tub at full capacity which by the way is over 6000 pounds.

If you just bought one and wondering does a hot tub have to sit on concrete then you are in the right place. No, a hot tub doesn't have to sit on concrete but it's recommended to do so. Concrete is a strong and recommended base for hot tubs.

What Is the Best Base for a Hot Tub?

Generally, the best base for hot tubs is a concrete slab. The concrete slab is usually set up by first digging about 2 feet or more into the earth and then filling the space with gravel before pouring the mixed concrete paste. When the mixture solidifies, you will end up with a very strong base for any hot tub.

Not only that, a concrete slab gives you the luxury of beautifying your hot tub space anyhow you want to. Any additional detail, be it artificial grass, flowers, and the likes will fit and blend perfectly on a concrete slab.

While concrete slabs are the most common base used by many hot tub owners, it isn’t the only base capable of carrying the full weight of a hot tub.

Other popular choices include hot tub pads, pavers, gravel, and reinforced decks. Overall, the best base for your hot tub depends on your decision, the qualities of the base, the hot tub model you have, and the capacity of the hot tub too.

Related Read: Can You Put A Hot Tub On Grass?

How Thick Does a Concrete Need to Be for a Hot Tub?

A concrete slab needs to be about 4 inches thick, it should be able to support about 120 pounds (54 kilograms) per square foot, and it should be wider than the bottom part of your hot tub.

Any base required for a hot tub must be level, strong, and wide enough to support the weight and size of the hot tub without any problem.

A hot tub at full capacity can weigh between 3000 pounds to over 6000 pounds depending on the model and size. If the concrete slab isn’t thick and strong enough, it will start to crack and eventually give way. That will ruin the concrete slab not to mention the damage it will also cause to the frame of the hot tub.

Asides from the thickness of the concrete slab, you should also allow the concrete to get cured fully. Curing is a term used in construction used to refer to the process of adding adequate moisture, temperature, and time to allow the concrete to reach its full desired properties.

In simple terms, after setting up the fresh concrete slab, you should regularly supply water to the concrete daily. You can even do it twice daily depending on how hot it is where you live.

The water will allow the concrete mix to solidify and get stronger. It is always advised to do this daily for about 3-4 weeks before attempting to place a hot tub on the slab. If you do not let the concrete cure fully, it’s the same thing as having a weak concrete base and that’s not good enough for a hot tub nor is it safe.

Related Article: Can An Inflatable Hot Tub Stay Warm In The Winter?

What Are the Alternatives to Putting a Hot Tub on Concrete?

A concrete slab is a common base for a hot tub but it isn’t the only base deemed suitable. There are different hot tub bases that a hot tub can be placed on, so it’s all about your hot tub and your choice.

1. Reinforced Wooden Deck

A hot tub can be placed on a wooden deck but you need to be sure the deck can support the weight of the hot tub at full capacity of water and bathers. A deck built at 2 feet above the ground level can support about 100 pounds per square foot of weight which is okay for many hot tubs but not all.

If you want to determine if your deck can support the full weight of your hot tub, then click the link.

Pros

  1. A reinforced wooden deck adds style and class to your hot tub space.
  2. A hot tub placed on the deck is closer to the home so you have increased comfort, security, and privacy.
  3. A reinforced deck is strong enough for even the larger 7-person hot tub.

Cons

  1. Reinforcing a wooden deck can be costly and is not usually a task you can execute yourself.
  2. A poor quality wooden deck can be discolored and weakened by the treated water from your tub.
  3. A wooden deck will need regular cleaning and maintenance which might not be your gig if you have a tight schedule.

2. Hot Tub Pads/mats

Hot tub pads are made from a variety of materials, mostly plastic. That it’s made of plastic doesn’t mean it can’t support the weight of a hot tub. Some hot tubs even come with their hot tub pad. The pad is a ready-made base for the hot tub.

As an added advantage over the concrete slab, hot tub pads are cheaper, lighter, and you don’t have to wait for 3 weeks before you can put your hot tub on them. You do need to pay attention to the instructions on your hot tub pad though.

Pros

  1. Hot tub pads are a cheaper alternative if you need a pocket-friendly hot tub base.
  2. They are specifically built for the hot tub.
  3. Hot tub pads are ready-made.
  4. Hot tub pads are easy to install.

Cons

3. Gravel

The low cost and ease of drainage make a gravel base another common choice for hot tub owners. A gravel base is strong, cannot be damaged by water, and it makes drainage easier.

Though the method of construction is somewhat similar to making a concrete slab, you should contact a contractor to do the measurement, recommendations, and help you out if you aren’t experienced with such tasks.

Pros

 Cons

There are other durable materials and bases capable of supporting the weight of a hot tub such as stone pavers. However, you need to consider the weight of the tub at full capacity, your budget, and available space among other factors before picking a hot tub base.

Related Read: Can An Inflatable Hot Tub Fit Through A Door?

I hope you found this article useful. Let me know if you have any questions or comments below and I’ll answer them as soon as possible. Have a good day.

Michael is the owner of hottubwiki.com. He owned several hot tubs and jacuzzies for over 15 years. He had a shop where he used to sell hot tubs. Now he enjoys writing helpful guides about hot tubs.