Once you’ve chosen and purchased your hot tub, you’re probably eager to jump in and enjoy your first soak — and we totally get it!
But before you dive into relaxation mode, there’s one essential step to take care of: preparing a solid, suitable base for your outdoor hot tub.
We always recommend our customers not to wait until the last minute. While you’re waiting for your hot tub to be delivered, it’s the perfect time to prepare a stable, level, and solid base in advance. A wood burning stove hot tub isn’t just a backyard feature — it becomes a long-term part of your outdoor space and lifestyle.
So don’t give in to the temptation of placing it directly on the grass. Without proper support underneath, the tub’s structure and equipment could suffer over time — and that could mean costly repairs and unnecessary stress.
What happens if your hot tub is placed on an improper base?
At first glance, it might seem like placing your hot tub on gravel or a wooden board is good enough. And yes — gravel is easy to lay down.
But without proper compaction using a vibrating plate, it won’t stay firm for long. Over time — sometimes just a few months, sometimes after a couple of years — you might start noticing problems: instability, uneven settling, or even damage to the tub’s structure. Not only can this ruin your relaxation experience, but such issues are usually not covered by warranty.
When the base isn’t level or begins to sink under the weight, the bottom of the hot tub can start to warp and bend. On an uneven surface, the water inside distributes unevenly, placing irregular pressure on the tub’s frame. Over time, this added stress can lead to cracks in the insert. An unstable foundation is especially risky for wood burning stove hot tubs with integrated heaters and technical systems. Structural distortions may lead to damage in the insert, hydromassage and filtration systems, lighting components, and more. A shifting or sinking base can also cause sealing issues — water may start leaking through misaligned joints. And if the tub is placed directly on soil or grass, constant moisture, seasonal shifts, and uneven ground can accelerate wood decay and mold growth.
Base for a hot tub: our recommendations
There are several reliable ways to create a proper base for your outdoor hot tub — your choice will depend on your yard layout, design preferences, and budget. The key is to ensure the surface is solid, level, and well-draining. This directly impacts your hot tub’s longevity, your safety, and overall comfort when using it. Below, we highlight four of the most common and proven foundation options.
1. Wooden decks and platforms
A wooden platform or deck is one of the most visually appealing options — especially if you want your outdoor hot tub to blend naturally into your garden or backyard.
Decking adds warmth and charm, but it’s important to ensure the structure is engineered to support the full weight of the filled hot tub (including water and people). Before choosing this option, keep in mind that wooden decking requires maintenance. To stay resistant to moisture and sun exposure, it should be treated with wood preservative every 1–2 years.
If you prefer a low-maintenance solution, you may want to explore other base options.
2. Crushed stone (gravel) base
A compacted gravel base is an economical and practical solution — especially if you plan to prepare the outdoor hot tub foundation yourself. It’s typically installed level with the ground, so the tub sits at the same height as the surrounding surface. Gravel provides excellent drainage, preventing water from pooling underneath after rain. We recommend laying a layer at least 20–30 cm (8–12 inches) thick and compacting each layer thoroughly with a vibrating plate. A layer of geotextile fabric underneath is essential — it prevents weeds from growing and helps keep the base stable. To avoid the gravel shifting over time, it’s worth installing edging or borders. This is an ideal choice for cottages, country homes, or any space where you want a simple yet reliable base without large investments.
3. Concrete pavers
Concrete pavers are a long-lasting, stable, and visually neat solution, suitable for both modern and traditional yards. If needed, individual damaged pavers can be replaced without redoing the entire base. For maximum stability, install a compacted gravel and sand layer underneath, and ensure a slight slope for drainage. This type of surface requires minimal maintenance and stays neat for many years. Plus, pavers can be matched with walkways or patio areas in your yard, creating a seamless and cohesive design.
4. Concrete slab
The strongest and most durable foundation for a hot tub — and the one we recommend most — is a poured concrete slab. The recommended thickness is at least 10 cm (4 inches), reinforced with steel rebar. This type of base won’t shift, settle, or require much maintenance. When installing, it’s important to plan a slight slope away from the tub so rainwater or condensation doesn’t accumulate underneath. While a concrete slab is a more expensive option, it pays off in longevity and reliability. It’s especially suitable if your hot tub will be used intensively and year-round.
Outdoor hot tubs integrated into decking – what you should know
Inspired by stunning examples, many Maudis customers dream of having their outdoor hot tub seamlessly built into a deck.
It’s an eye-catching solution that creates the feeling of a private spa retreat. But before you make the final decision, there are a few important things worth knowing. Drawing from our years of experience, we’ve prepared some recommendations to ensure your deck-integrated tub is not only beautiful, but also practical.
Installing a hot tub into decking requires thoughtful planning. First and foremost, make sure there is easy access to all technical components — filters, pumps, and control units.
The best approach is to plan for removable deck panels or to position the tub near the edge of the deck. You should also evaluate the deck’s structural strength, the finish around the tub, and — most importantly — the base underneath. The surface beneath your wood burning stove hot tub must be strong and level. You can follow the leveling and foundation preparation methods described earlier to ensure long-term stability.
Installing the stove
If your hot tub is heated with a wood-burning stove, you need to ensure there’s a safe way to route the chimney. Both the chimney and the stove must be installed at a safe distance from any combustible deck elements or roof structures. The safety clearance between the outer surface of the insulated chimney and combustible materials should be no less than 100 mm (4 inches). The stove must be placed on a non-combustible base, such as metal or stone, to ensure safe operation. In many cases, people opt for a tub with an external stove, positioning it in an open space for better safety and convenience.
Alternatively, you can choose electric or hybrid water heating — a particularly convenient option for effortless operation. With an electric heater, you avoid the hassle of preparing firewood and dealing with wood debris around the tub area. At Maudis, we offer premium Gecko heating systems that maintain a constant water temperature, with all functions easily controlled via the integrated display on your tub.
Don’t forget — rainwater and runoff must be directed away so moisture doesn’t collect under the tub and damage the electrical components.
For maximum safety, we also install a residual current device (RCD) in our tubs, which protects users from electrical hazards. Lastly, think about a safe and comfortable entry, especially for a lower-profile, deck-integrated outdoor hot tub. Since this type of installation is more complex, we recommend carefully weighing the pros and cons.
If possible, consult professionals — this will help you avoid costly mistakes and ensure your tub serves reliably for many years. A well-planned solution will give you a comfortable, beautifully integrated, and easy-to-maintain relaxation spot in your backyard.
A well-chosen and properly installed foundation is one of the most important steps in ensuring your hot tub will last for many years, remain comfortable to use, and stay safe.
Whether you opt for a wooden deck, concrete pavers, or a sturdy concrete slab, each option has its own advantages worth considering. The Maudis team is always ready to help you choose the solution that best suits your needs, so you can enjoy your outdoor hot tub for many years — without the stress or unexpected problems.
