Hot Tub Foundation Guide – 5 Ways To Ensure Spa Stability

hot tub foundation

Have you just invested in a spa and are beginning to prepare your backyard for its arrival?

It’s an exciting time when you finally take the leap into soothing self-care, transforming your backyard into a healing haven of relaxation.

But wait…there are some crucial steps you’ll need to take before delivery day, and one of the most crucial is getting your hot tub foundation ready!

Your foundation is a vital element of your hot tub installation and requires careful consideration.

Curious about where to begin? Fret not, we’ve got you covered, with everything you need to know below!

In this article, you’ll discover five different hot tub foundation options, important factors to consider when choosing your location and explore two popular hot tub installation styles.

Read on, and let’s get your backyard prepped for your spa’s arrival!

Note: For best results, we recommend consulting with your hot tub dealer for recommendations based on your hot tub model and backyard layout.

Why is Your Hot Tub Foundation Important?

Your hot tub foundation plays a crucial role in your spa’s longevity and stability, and its importance cannot be overstated.

One of the most common questions when it comes to installing a hot tub is: “Can’t I just install my hot tub on the grass?”, and honestly, this is a big no-no.

Here’s the thing–your hot tub isn’t light, and if it’s placed on your grass, there’s no ensuring it doesn’t slowly sink into the ground over time.

This is where a stable foundation comes into play. There are two essential requirements when it comes to your foundation:

  1. It’s level.
  2. It’s strong enough to support your filled spa and guests.

As long as your foundation meets these requirements, you’re in good shape! So, what could you use for your foundation?

Explore your options in the next section!

hot tub foundation - hot tub on a deck

5 Different Types of Hot Tub Foundations

Hot tub foundations can come in many styles, making it possible to easily blend your spa into your backyard aesthetic and curate the backyard experience you’re envisioning.

Here are five of the most common hot tub foundation options you’ll be able to choose from as you prepare your backyard.

1. Concrete

A concrete slab is easily the most widely used hot tub foundation.

Not only do they offer an exceptional study base that’ll reliably support your spa for years to come, but they are easy to install and ultra-affordable.

Ideally, you’ll want your concrete base to be at least four inches thick, with six inches being highly recommended, ensuring it’s hefty enough to support your spa without weakening over time.

You’ll also want to be mindful of when you install it. Concrete takes time to cure, and if it experiences drastic temperature fluctuations during this process, its stability can be compromised.

Furthermore, it’s worth considering adding an extra layer of support beneath your slab, such as rubble or rebar, reinforcing your foundation for maximum strength and longevity.

If you’re looking for a foundation that’s durable, reliable, and affordable, a concrete slab is definitely the way to go.

2. Crushed Gravel

Another common option is crushed gravel. Now, this is not to be confused with pea gravel, which has a smooth surface.

Crushed gravel has rough edges, which is crucial to its stability once your spa is placed on top.

These ridges along their surface allow the rocks to lock together, instead of sliding across each other and weakening under the pressure of your spa like pea gravel would.

Gravel also allows for superb drainage, which is a key element in your installation, ensuring water is easily able to flow away from your spa’s base.

If you opt for crushed gravel, keep in mind you’ll need a retaining border around it to firmly keep your gravel locked in place, maintaining stability.

You’ll also want a hard surface under it. Do not place it directly onto the ground and set your hot tub atop. Without a base, the gravel will sink into the ground over time.

If you’re looking for a foundation that’s visually appealing and provides ample stability and drainage, crushed gravel is an excellent option.

3. Paver Stones

Paver stones are a great way to seamlessly integrate your hot tub foundation with your existing backyard features.

These stones come in various colors and styles, making it possible to create a truly unique hot tub foundation.

For a hot tub, these paving stones should be no less than two inches thick. If they’re any thinner, you’ll risk them cracking under the weight of your spa, quickly deteriorating your foundation’s stability.

To maximize their longevity and durability, you’ll want to install a solid base below, topped with sand or gravel.

You’ll also want to sweep sand between the cracks after you’ve set your pavers into place. This will add an additional layer of stability, locking everything into place.

If you’re hoping for a DIY hot tub foundation, pavers are not the way you’ll want to go. Pavers can be difficult to perfect and level out, and without a level surface, you risk causing damage to your spa.

We highly recommend consulting with a professional when it comes to installing pavers as your hot tub foundation.

4. An Existing Deck or Patio

Have a deck or patio already in your backyard and want to significantly reduce the expenses of your installation?

These pre-existing structures can be the perfect way to maximize the elements already in your backyard, however, they require some consideration beforehand.

First and foremost, you’ll want to ensure your patio is in good condition. If its stability is compromised, or it has any structural damage, it’s not suitable for your spa.

You’ll also want to make sure it’s perfectly level and capable of supporting your spa’s filled weight.

This will ensure the weight of your spa is able to be evenly distributed throughout, ensuring your spa doesn’t fall victim to structural damage over the years.

For a pre-existing deck, you’ll want to ensure you have it inspected by a professional prior to using it, ensuring it can support the weight of your spa, and doesn’t have any structural concerns.

5. A Spa Pad

For potentially the easiest solution, a spa pad may be the answer you’re searching for.

These prefabricated hot tub foundations can easily be added to your backyard, providing your spa with the support they need.

For this foundation, you’ll need to clear your selected area of grass and topsoil to ensure a level, stable installation.

If you’re looking for a foundation that offers maximum flexibility, spa pads are the way to go, easily being the least permanent solution.

hot tub foundation - hot tub on a patio

Additional Considerations When Installing Your Hot Tub

Apart from your foundation, there are a few other essential elements you’ll want to consider as you prepare for your hot tub’s arrival.


First and foremost is where you want your spa installed.

Ideally, this should be chosen before choosing your hot tub to ensure you invest in a model that fits in the space, with enough clearance around for easy maintenance and accessibility.

As you consider the areas of your backyard that would be best for your new luxury escape, you’ll want to consider the following aspects:

  • Privacy
  • Proximity to your house
  • Nearby water sources
  • Your spa’s electrical needs

By taking each of these elements into consideration, you’ll be able to ensure your spa will be easy to hook up, maintain, and enjoy.


This is a multi-faceted element of your hot tub installation. Not only will you want you and your guests to easily enter and exit the spa, but you’ll want to ensure you have access to your system.

This ensures you can easily maintain your spa once it’s installed. Ideally, you should have at least a few feet around your hot tub to allow for easy access.

Local Codes & Permits

If you’re adding a structure to your backyard, such as a deck, you may need to adhere to certain regulations and obtain permits.

Prior to installing your spa, check for any permits or requirements that may be required when adding a structure to your backyard.


We mentioned drainage above, but its importance cannot be overstated. The last thing you want is the base of your spa being compromised because of pooling water.

As you plan your installation, consider how water will drain away from your spa when it rains or as snow melts.

hot tub foundation - semi-recessed hot tub installation

In-Ground Installation vs Above-Ground Install

When it comes to actually installing your spa, there are a number of ways to do it, and which one you select will greatly depend on your budget and the aesthetic you’re aiming for.

In-Ground Installs

In-ground hot tub installations offer a stunning visual appeal, providing a high-class approach to your backyard design.

Sunken into the ground, this design ensures your hot tub becomes a truly seamless addition to your backyard, however, it comes with some considerations.

These installs require more planning and work, increasing installation costs. Additionally, it also changes how easy it will be to maintain your spa, especially when it comes to repairs and service.

For this type of installation, you’ll want to ensure you leave ample space around the edges of your spa, installing a trap door to ensure both yourself and a service technician can reach your access door.

To achieve this aesthetic without the added costs and maintain accessibility, consider installing your hot tub alongside a raised deck.

Above-Ground Installations

This style of installation is easily the most affordable and popular.

While you’ll need to pair your hot tub with steps to make getting in and out easy, this type of design allows your hot tub to become a captivating centerpiece in your backyard.

It’ll be the first thing people notice when they walk into your space – especially a hot tub that features premium cabinetry with accent lighting, such as the Altamar®️ hot tub or Claremont®️ model.

Hot Tub Installation FAQs

Do I need to have a foundation for my hot tub?

A foundation is a crucial element of any hot tub installation, supporting your spa and keeping the weight evenly distributed, maximizing your spa’s longevity, and maintaining its quality.

Should I hire a professional to install my hot tub?

While there are DIY options when it comes to installing your spa, there are elements that will require professional assistance, such as installing the electrical hookup.

As you move through the process of preparing for your hot tub’s arrival, the team of experts at your dealer will be your best resource for a flawless experience.

How soon can I use my hot tub after installation?

Once your hot tub has been installed, you’ll need to give the water time to come up to temperature before settling in for your first soak.

This can take a number of hours, ranging anywhere from four hours to eight, depending on the size of your hot tub. You’ll also want to ensure you don’t soak too soon after adding chemicals to your water.

Luxury Hot Tubs for Sale in Greensboro and High Point, NC

Installing your hot tub is a process that requires careful consideration, but with the right team by your side, it can be truly effortless, ensuring you move through every step with confidence.

That’s where the team of backyard leisure experts at AquaVision Pool & Spa comes in.

We’ve been serving Greensboro and the Triad for over 40 years, transforming backyard relaxation with expert guidance and premium products.

Our showroom is stocked with top-of-the-line hot tubs from Sundance®️ Spas, ensuring every person who walks through our doors finds nothing but luxury.

Ready to embrace a life of blissful backyard relaxation? Visit our Greensboro or High Point showroom today or contact your local team to learn more.

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