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In this detailed guide, we’ll show you how to level a hot tub on pavers or concrete. Making sure that your hot tub remains level is very important, otherwise the water is going to slosh over to one side.
If the ground below your hot tub has shifted slightly over time, the hot tub will not remain level, and this could prove to be a major problem later on. The best way to level a hot tub is to make use of heavy-duty plastic shims.
There are several manufacturers who generally do not recommend the use of shims, and even claim that their use will render your warranty void. However, you should avoid using shims if the hot tub’s unevenness is greater than 1” when compared side to side.
In such scenarios, the best option will be to opt for a new foundation or to go for a bed of framed sand. It’s best to check whether the sand has been compacted and is level before you decide to go for it.
However, that’s not all. There are quite a few other things that you should keep in mind about leveling a hot tub, primarily if you do not want the shell or the outer frame to suffer from cracks in it. Let’s talk about these details.
How to Level a Hot Tub on Concrete
Hot tubs primarily rest on concrete slabs or reinforced decks, but what if the concrete slab is not level and is set on a slope? What is the best way to level a hot tub on uneven concrete?
If you have no other option but to rely on a sloped slab, fixing the hot tub is actually quite easy. You just have to make use of shims to level the hot tub properly.
First, you will want to check whether your hot tub supports the use of shims. If it does, great! Next, you need to buy a set of high-quality shims that you can use with your hot tub.
Keep in mind that virtually any hot tub can be supported using shims, regardless of whether or not the manufacturer allows it. However, whenever you do use shims, it’s important to follow a set of important guidelines.
More importantly, there is an element of risk involved, so you need to know how to mitigate it properly. Ideally, you should begin from the lower end. Tap the shims in place so that they offer adequate support to the shell and the frame.
Needless to say, it’s highly recommended that your hot tub is empty when you add the shims. It’s going to be considerably easier for you due to the reduced weight and the risk will decrease as well.
However, if the slope is greater than an inch (you can measure it using a level), shimming might not be the best option available to you. In this situation, the best option available to you would be to move the hot tub.
Or, you might want to take steps to balance the hot tub. You can either make use of gravel or framed sand to level the surface before placing the hot tub back on it.
Similarly, if your hot tub doesn’t support shims and you don’t want to void the warranty, your only option will be to pour in a new concrete slab.
Even though concrete is the ideal choice in most situations, you should know that your hot tub can sit on a number of different surfaces apart from concrete.
How To Level a Hot Tub on Pavers
There are several different kinds of pavers that you can select for your hot tub. Common options include rubber, flagstone, brick, cobblestone, and concrete.
However, before you opt for pavers, there are a few things that you should know. Raised pavers that have ridges are likely to increase the level of stress on the outer shell of your hot tub.
You need to choose pavers that are relatively smooth and interlock, thus creating a flat surface. This is going to prevent any unevenness.
Pavers are a pretty good option due to their higher density; they also offer greater support than wood or concrete slabs.
The absorption rate is relatively good, which makes pavers quite resistant to problems that you would otherwise experience with poured concrete.
For instance, it’s completely resistant to common problems such as salt scaling and efflorescence. These are just a few things that you should know about leveling your hot tub on pavers.
Is it Necessary for the Hot Tub to Remain Perfectly Level?
To put it simply, the answer is yes. You will want to make sure that your hot tub remains as perfectly level as possible. This ensures that the water sits evenly instead of pooling over to a specific side.
However, that’s not the only reason why you should keep the water level. The average hot tub has more than 600 gallons of water in it.
The additional pressure of thousands of pounds of the tub teetering to one side, compounded with the excessive volume of water, will cause the frame to crack. When it is leveled, the pressure and weight will be distributed across the entire frame.
When the tub is not level, it increases the amount of weight to specific areas on the frame. Since most hot tubs have an acrylic shell, you should know that it doesn’t take long for fractures or cracks to appear.
If the number of cracks increases, it doesn’t take long before the hot tub is rendered unusable. Most people like to keep their outdoor hot tubs on decks or patios that are usually made out of firm materials such as concrete or brick.
But, that’s not the only option available; you can keep your hot tub uniformly on any kind of surface, as long as it is solid and levelled. However, it would not be a wise idea to keep your hot tub on grassy surfaces.
Avoid keeping the hot tub on bare ground because that tends to shift from time to time, and it’s not something that you will want to happen under your hot tub.
When you are placing a hot tub indoors, you should just opt for any kind of regular floor as long as it complies with local building codes. The concrete floor in the basement is an excellent choice, but you can also place the hot tub on a porch.
However, if you are going to keep it on a porch, you need to follow the same protocol as you would when keeping it on a wooden deck: check to ensure that the porch is able to support the weight of the hot tub before you do.
What Happens When the Hot Tub Is Not Level?
The damage caused to your hot tub can be quite serious if it is not level: it could break altogether. Most people only think that the water level will be off, but that’s not the only thing.
Since one side of the hot tub’s frame will hold higher amounts of water, the pressure will be greater. As a result, it is susceptible to breakage over time.
As stated above, the average hot tub is built to seamlessly distribute thousands of pounds of weight across its shell, which is usually made of acrylic.
This weight is divided between the water and the people sitting in the tub. But, if the weight is not properly balanced, it is susceptible to breakage. With the passage of time, the amount of stress on the acrylic shell will continue to increase.
If the foundation is not properly set or if the hot tub is not leveled, it could cause the whole outer shell to crack. In most cases, a tiny dip in the ground is also likely to cause the hot tub shell to crack.
In the simplest of terms, this is nonnegotiable; you need a solid foundation for the hot tub. If the foundation is not level and firm, you will end up spending even more money than you would on a firm foundation.
Apart from that, you should know that wooden decks are a very common choice for people to keep their hot tubs on. However, before you go ordering a wooden deck, you need to factor in the maximum weight that it can hold.
Can I Use Shims for Leveling the Hot Tub?
In a nutshell, yes you can. Shims can be used to level your hot tub with ease. A lot of people do not find it financially feasible to tear out the ground from underneath their hot tub and then replace it with a level foundation.
This is where you might want to consider using shims. If you take a look underneath your hot tub, you will realize that a vast majority of them come with shim points.
The best thing to do is go through the owner’s manual. You will find information about whether your hot tub is equipped with shim points or if there are none.
More importantly, the owner’s manual will also guide you about where they are. Comprehensive owner’s manuals provide detailed guidance about how to add shims.
But, there are several brands that do not support shims. Jacuzzi, one of the biggest hot tub manufacturers, does not support shims. Obviously, this doesn’t mean that you can’t install them or they won’t work.
You can still retrofit the shims on these hot tubs, but it’s going to render your warranty useless. Therefore, it’s best to proceed with caution in such situations.
More importantly, using wooden shims is definitely not a good idea. There have been many situations where after a few years the shims tend to rot. As a result, using wooden shims is definitely not a wise idea.

Hello, my name is David Zal and I’m a plumber with more than 20 years of experience based in Englewood (Florida). I like to teach normal people how to make easy fixes in their homes. I believe that a lot can be achieved just with DYI and that’s why I started this blog.