Your hot tub needs a solid, level foundation to be installed on. The area where your hot tub sits must be able to support the weight of the hot tub, the water in it, and those who use it. If the foundation is inadequate, it may shift or settle after the tub is in place, causing stress to its shell. While concrete is a great option, your hot tub can be placed on any stable, level surface that will not become unstable due to moisture or weight. Other installation surfaces include wooden decks, paver stones, gravel beds, or spa pads. Do not place your hot tub on grass or bare ground. 

What’s the Best Base for an Outdoor Hot Tub?

When selecting a base for your hot tub, it’s important to consider several factors. First and foremost, you need to ensure that the foundation is strong enough to support the weight of the hot tub full of water, plus the weight of anyone using it. Hot tubs are heavy, and your base must have a minimum of 125 pounds per sq. ft. load bearing capacity, and additional bracing if necessary. New concrete pads should be a 4″ minimum depth with reinforced wire placed in the concrete, and new wood decks should have 2 x 10 floor joists and 4 x 4 or 6 x 6 posts depending on deck height. Existing decks and concrete patios should be inspected by a licensed contractor to determine adequate support. 

Additionally, the surface on which you plan to install your hot tub must be perfectly level. This is essential for proper drainage and preventing the hot tub from becoming unbalanced and potentially damaged over time. Concrete pads are great for hot tubs because they provide a solid foundation that’s resistant to weather. They also don’t require additional framing or support, so installation is relatively simple. It can be expensive to hire a professional to pour the pad, and it’s not moveable if you decide to relocate your tub. 

Concrete can crack over time due to shifting soil or weather conditions, and if aesthetics are important, it’s not the most attractive material. If you feel that a concrete pad might not be the best fit for your needs or budget, here are other some options:

• Gravel or crushed stone: a layer of compacted gravel or crushed stone can serve as a solid base for the hot tub. It’s an excellent choice if durability is your priority, because it won’t crack or shift over time like concrete can. It also allows for good drainage and helps prevent the tub from sitting in standing water.
• Pavers or patio stones: interlocking pavers or patio stones can be used to create a stable surface for a hot tub, just ensure the ground beneath is appropriately leveled and compacted to prevent uneven settling. Pavers can add visual appeal to your tub area as they come in various shapes, sizes, and colors, and as with gravel, they provide stability without cracking or shifting over time.  
• Deck: If you have a sturdy deck with the appropriate load-bearing capacity, it can be a great foundation for a hot tub. Decks are a popular choice because they look great and you can create a comfortable seating area or entertaining space around your tub. 
• Prefabricated spa pads: these pads made from recycled plastics are designed specially for hot tubs, and provide cushioning between the tub and the ground. They’re lightweight and can be moved more easily than other types of foundations.

Whatever foundation you decide on, make sure your hot tub is positioned so you have full access to the equipment compartments located by the spa controls. It’s also wise to design an installation where the entire hot tub can be lifted or removed if needed. 

What’s the Best Foundation for an Indoor Hot Tub?

Indoor hot tubs are an alluring prospect, and with the right planning, they can be an exciting new addition to your home. When your hot tub is installed indoors, it’s better able to stay at one temperature, which helps reduce its energy use. It’s also protected from the elements, leaving your water clean and free of contaminants like insects, dust, and leaves. While it’s convenient and private, installing your hot tub indoors is often expensive because it takes more work for the technicians to get it into the room and set up.

If you plan on installing indoors, you’ll need to make sure your hot tub can fit through your doorway, or you’ll have to build a separate room. Your foundation needs to be strong enough to support your hot tub’s total weight after it’s been filled, and perfectly level. Before you install your spa, plan how you’ll drain your hot tub when it comes time for its quarterly clean and how you’ll remove water that splashes on the floor during use. One option is installing a sump pump below your spa and a floor drain on the surface of your floor. 

A cement slab is a common base for both indoor and outdoor hot tubs. A garage or basement could be a great spa location because those areas typically have a solid concrete foundation that’s level, which is exactly what you want for a hot tub. Other foundation options are water-resistant floor material like sheet vinyl or tile, or ceramic tiling with an anti-slip or matte finish. Do not put your tub directly on household carpet or a wood floor! Make sure to install your tub somewhere that can withstand water and humidity and remember you’ll also need some sort of ventilation system like an extraction fan, much like the ones in bathrooms.

Regardless of the foundation type you choose, it’s crucial to ensure the surface is level, firm, and capable of supporting the hot tub’s weight, water capacity, and the weight of its occupants. Give us a call with questions at 970-879-4390 or contact us here and we’ll help make sure your hot tub is installed properly.