Do Hot Tubs Need a Foundation?
- The average hot tub will hold approximately 475 gallons of water. Water weighs 8.34 lbs. per gallon, which means your hot tub will weigh nearly 4,000 lbs.; that's 2 tons. Fortunately, this weight is spread evenly across the base of the tub, but with this amount of weight, careful site planning will still be required.
- When selecting the site for your hot tub you will need to have a level area, access to electrical power and reasonable access to a water supply. If the area selected is not level, you will need to construct a level platform on which the hot tub can sit.
- The weight of the hot tub will be evenly dispersed across the platform on which it sits. It is critical this platform be level, or the weight will be off center and could void your warranty. The platform does not need to be made of concrete but must be of adequate strength to support nearly 3 tons of weight. (The weight of the tub, water and its occupants.)
- A concrete slab offers a solid base for a hot tub but also offers the least mobility. A sturdy wooden deck can easily support the weight of the hot tub, and should it be necessary, can be moved much easier than a concrete slab. The hot tub should not be placed directly on the ground to prevent rust, rotting and potential settling.
- If pouring a concrete slab, make it at least 4 inches thick. If building a wooden deck, use wide concrete blocks at the base of your support columns. The broader the footprint of your support, the less likely you are to experience settling. Wooden columns placed directly on the soil will tend to sink under the weight and will also be subject to rotting.
How Much Does You Hot Tub Weigh?
Site Selection
Hot Tub Support
Types Of Platforms/Foundations
Foundation Support
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