Hot Tub Weight: Why is It Important and How to Calculate?

In this article, we explore the weight of hot tubs including 4-person and 6-person models, both full of water and empty.
Deborah Beams
Deborah Beams
Research Writer
Deborah is an incredibly talented journalist who's been working for numerous online magazines for over 8 years now. She's also our main research writer who can turn any bori read more
Reviewed By
Charles Eggleston
Charles Eggleston
Expert Consultant
Charles's been a plumber his entire life. Thanks to his vast experience we can always rely on Charles' expert opinion when creating any of our articles. He's also a fantasti read more
Last updated: September 12, 2023
Bathroomer is reader-supported. We may earn a commission through products purchased using links on this page. Learn more about our process here

Having a hot tub in your home or garden has become much more common in recent years. They’re not necessarily the extreme luxury they once were. In this guide, we explore the weight of hot tubs. There are many different designs of tub out there and though you may be able to find an average hot tub weight, it makes sense to work out exactly how much your model weighs.

Whether you need to know a 6 person hot tub weight or an 8 person hot tub, we’ve explored how you can find the weight of a model and why it is so important. We even show some useful calculations to work out how much the tub will cost as soon as it has been filled with water.

What should you know about the weight of your tub?

Hot Tub Weight: Why is It Important and How to Calculate?So, how much does a hot tub weigh? Obviously, not all hot tubs are created with the same sort of design, there are a lot of things that go into the weight of a tub such as the materials it is made out of. This is the same of bathtubs, when acrylic tubs are much more likely to weigh less than a cast iron model.

Hot tubs generally can weigh between 600lb and 800lb, but this is a rough guideline and there are always exceptions.

For instance, some people use inflatable designs and these hot tubs can be an efficient way of doing things. Even an 8 person hot tub weight isn’t likely to be huge if you can deflate the tub itself.

Why does it matter so much? Well, for one thing, it is possible that you might have to move your hot tub. They’re not always kept in the same position like your bathtub.

Some whirlpool tubs with similar features to hot tubs weigh just a fraction of the weight of a hot tub, whether you’ve got a four person hot tub or a much bigger model.

How to find out the weight of your tub

Finding the weight of your hot tub is not easy if you need to work it out yourself. Instead, you should get the information from the manufacturer’s website or the site where the tub is for sale. For example, this model from Essential Hot Tubs is 630 lbs, as outlined on the selling site. When the weight of a hot tub is listed on these sites, it is going to be the “dry” weight which means the weight when there is no water within. This is the same way that any bath tub such as a cast iron tub is measured.

If a manufacturer doesn’t list the weight of their tub, it is only natural to drop them an email or a message to ask this question, most will be happy to help. It isn’t always listed, as some manufacturers know the majority of people are using their tubs are doing so outside and aren’t too worried about the weight.

How much does a full tub weigh?

Hot Tub Weight: Why is It Important and How to Calculate?So, how much does a tub weigh when it is full? This will require some maths, but if you know the weight when empty you can calculate the weight of the tub when it is full with a high degree of accuracy.

We know that one gallon of water weighs 8.34 lbs Trusted Source How Much Does a Gallon of Water Weigh? - WorldAtlas A gallon of water weighs around 8 pounds at its most dense state. . So, if you know the capacity of the tub in gallons then you will be able to work it out. The temperature of the water does impact on the weight, so it is worth keeping this in mind. However, it won’t make a huge difference. Remember that these are not perfect calculations.

If your hot tub has a capacity of 400 gallons, you can multiply 400 by 8.34 lbs to work out the weight of the water inside. In this case, the sum gets us the answer of 3336 lbs. Next, you can add this calculation to the weight of the tub when it is empty, and you will know the weight of your full tub, and how much pressure you are putting on any flooring that it is situated on top of.

Even a plug and play hot tub with inflatable sections can weigh a huge amount once it has been filled with water. The more portable and lightweight options have come a long way and without costing a lot or being too difficult to move, they are still able to hold a fair amount of water.

How much does an empty tub weigh?

How much does a hot tub weigh empty? This depends on a number of factors including the manufacturer and materials used to make the tub. The average hot tub weight is 600-800 lbs when empty. When it is time to move your tub, you will be doing it when it is totally empty of water, so this is the most important factor to consider when you are working out whether you and your friends can move the tub or if it will be set in place.

If you look at inflatable tubs they might just weigh a few lbs. There is an incredible difference in these types.

Final thoughts

A hot tub is seen as a luxury item by many, but the truth is that there are options for anyone. It is vital that you know the hot tub weight so that you can calculate the strength of the foundations that need to go underneath, and also establish whether it is possible to move the hot tub. Naturally, you need to know the weight when the tub is full, too, as this will put more pressure on all of the foundations. If you don’t have the capacity for a big and heavy tub, you can always opt for an inflatable option, which are a safe yet cheaper and lightweight alternative for virtually any home.


How Much Does a Gallon of Water Weigh? - WorldAtlas
A gallon of water weighs around 8 pounds at its most dense state.
Leave a comment

Your email address will not be published. Required fields are marked *