Hot tubs are a great place to relax as you soak your stress and troubles away after a hectic day at work. They are immensely therapeutic. But they aren’t lightweight structures – at least, not when they’re filled. The weight of a hot tub is an important consideration when you look at where you’re setting it up.
Let’s take a look into why you need to care about the weight of a hot tub, and how to calculate the weight of yours.
Inflatable hot tub weight – quick stats
Here are some quick stats about the weight of inflatable hot tubs:
- The average inflatable hot tub weighs 88lb when empty (based on 50 hot tubs from 3 leading brands)
- Water capacity tends to fall between 500 liters and 1,500 liters (1 liter = 2.2lb)
- The average hot tub for four people, when occupied, will weigh around 2,500lb
Why does the weight of an inflatable hot tub matter?
The weight of inflatable hot tub matters because it determines whether or not a deck or terrace can support the tub.
Normally, a deck that is built at ground level or up to 2 feet above the ground can comfortably support up to 100 pounds per square foot. However, if the deck is higher than two feet above the ground, extra support would be needed. Otherwise a large hot tub, or one filled to capacity, could go crashing through.
Either way, it is advisable to reinforce your deck if it is higher than two feet, whether the inflatable hot tub is heavy or not. This provides additional security and provides a gateway to a permanent hot tub later on.
You can reinforce a deck using a concrete slab, or using additional joists to help spread the weight of the deck.
How much does a hot tub weigh empty?
A regular hot tub will weigh around 500lb when empty, while an inflatable hot tub is much lighter – typically 50-165lb when inflated. Most 4-person inflatable hot tubs will weigh around 90lb without any water added.
This is useful information to know, because while you’ll never really use your hot tub empty, you might want to move it around at some point.
If you’re buying a hot tub to use only with your partner, you might’ve been thinking about a larger one for more space – but if you like the idea of relocating it, you might prefer something smaller that weighs 50lb when drained, instead of three times the weight.
If you’re planning on keeping your hot tub as a permanent installation, then the empty weight is less important.
How much does a hot tub weigh when full?
Depending on the size of the hot tub, it’ll likely weigh between 1500lb and 4400lb when filled with water. You can then use the average of 180lb for each adult that will be using the hot tub to determine the total weight when in use.
That 400lb difference between a regular hot tub and an inflatable one when they aren’t filled might not seem huge when you consider the massive weight of the water, but it could be crucial when comparing whether an inflatable or solid hot tub is more suitable for your deck.
The weight of a hot tub depends on the size and shape of the tub, the material that it’s made out of, and the water capacity. But there’s something else you need to consider too – the weight of the people using it.
Remember that the difference between inflatable and solid hot tubs is around 400lb when empty. But if you had an inflatable hot tub with 6 people in it, compared to a solid hot tub with just 2 users, the weights would likely be the same.
And these are just the weights for a hot tub that’s considered a regular size. There are larger hot tubs that offer more space, and massive ones aimed at larger groups too. These can weigh up to 10,000lb when you factor in the weight of the people and the extra water.
Here’s a look at 9 inflatable hot tubs from three of the major brands. I’ve picked out the lightest option and the heaviest option from each brand, along with one that’s in the middle of each range.
|Hot tub model
|Weight when empty
|Weight when filled
|Weight when occupied
|Lay-Z-Spa Siena Airjet
|509 L / 134 G
|945 L / 250 G
|3,398 – 3,758lb
|1,540 L / 407 G
|5,429 – 5,789lb
|795 L / 210 G
|Intex Purespa Plus Bubble 6 Person
|1098 L / 290 G
|Intex PureSpa Jet and Bubble 6 Person
|1098 L / 290 G
|650 L / 171 G
|930 L / 245 G
|1100 L / 291 G
If you want the lightest hot tub for your balcony or deck, choose an inflatable two-person model like this one…
How to work out the weight of your hot tub
The empty weight of your hot tub, when inflated, will be included in the manual or the online product spec. That’ll also tell you the capacity in gallons – multiply the gallons by 8.3 and add that to the weight of the hot tub, and the people using it, to get your total.
Just remember that water weighs 8.3lb per gallon and you shouldn’t have many problems working out the weight of your hot tub. If you’re planning on using it with guests, and you don’t want to ask what their weight is (understandable!) then remember that the average weight of an adult is 180lb.
Frequently Asked Questions
You only need to reinforce your deck for an inflatable hot tub if the deck is more than 2 feet from the ground. Otherwise, it should be able to hold the weight of your hot tub with no issues as the weight will be pressing on the solid ground below.
Inflatable hot tubs are made with very light materials such as vinyl and PVC, while solid tubs are made with heavier materials like wood or ceramic. Inflatable hot tubs still weigh a decent amount when inflated because they are robust structures that can hold up to 100lb of air.
A typical 4-person hot tub will weigh around 90lb when empty, and between 1,500lb and 2,800lb when filled with water, depending on the size. Most of the weight comes from the water. Remember to then add the weight of the people on top – use a 180lb per person average if you don’t know!
When filled with people, a typical 6 person hot tub will weigh between 3,000lb and 6,000lb. The variations come with the size of the hot tub and how much water it holds, plus the weight of the people. The water weight makes up the majority, so choose a smaller one if you’re concerned.
Inflatable hot tubs offer a lot of benefits over solid hot tubs, including the option to deflate them during winter and protect them. They’re also a lot lighter, which could make them a good choice on an elevated deck.
You can even use inflatable hot tubs indoors if you wanted to, although again consider whether the flooring is suitable to support the weight. Don’t use them on elevated floors as the beams won’t hold the weight.