The Weight of a Hot Tub on a Deck

Hot Tub Weight

• The weight of a hot tub does not come from the hot tub unit itself. Constructed from wood, fiberglass and plastic, hot tubs are not that heavy for their size. Instead, the weight comes from the water inside the hot tub, as well as the bathers who use it. A hot tub full of water with four adults inside it can weigh a few thousand pounds. This weight is too much for most standard-built decks to support. The deck will crack and collapse beneath it.

Insert

• You can avoid a deck collapse by inserting the hot tub into your deck. The hot tub rests on the ground, with its lip just about even with the deck. You step down into the hot tub to use it. This offers the advantages of not needing to reinforce the deck itself, as well as providing an easy way to get in and out of the tub. In addition, when you run plumbing and electrical connections to the tub, they will be concealed beneath the deck, which makes for a more attractive presentation.

Reinforcement

• If you have a very tall deck or one that is quite low, a hot tub insert might not work. In that case, you will need to reinforce the underside of your deck so it can withstand the weight of the hot tub. Concrete pilings beneath the deck will hold the hot tub steady. Before putting them in place, have the ground beneath the deck leveled and checked for erosion or compression risks. You might need to install a new foundation beneath the deck for the piling. Concrete and rebar are strong enough to support the piling and the hot tub.

Considerations

• A hot tub is easiest to incorporate into a deck before it is built. If you are building a deck but have not yet decided on installing a hot tub, you can leave room for running new plumbing and electrical lines within the deck in the future. Before placing a hot tub either on or inside a deck, consult with a building inspector for your local area. Some municipalities forbid the installation of a hot tub on top of a deck. Inquire as well about electrical and plumbing codes before running any new lines.