If you're thinking of buying a hot tub, there are many things you must consider, especially when it comes to moving the hot tub to your home. One of the things is the weight of the hot tub, both empty and filled. You want to be sure that your deck or other surfaces can bear the weight
What does a hot tub weigh?
In general, empty regular small-sized hot tubs weigh 600 pounds but will increase to 3,000 pounds when filled with water and people. A regular mid-sized hot tub will weigh up to 4,400 pounds with water and people, or 750 pounds when empty, while a large-sized regular hot tub will weigh 5,500 pounds with water and people, or 800 pounds when empty. Of course, the weight of an inflatable hot tub will be much less and is mainly the water.
The brand of a hot tub is also a factor that can determine the weight of a hot tub, but it's generally within the range specified. In this article, I'll be showing you more about the weight of a hot tub and the effect of water and people on the weight.
- 1 What Does a Hot Tub Weigh?
- 2 What Weight Does Water Add to a Hot Tub?
- 3 Determining the Type of Foundation to Support Your Hot Tub
- 4 Frequently Asked Questions
What Does a Hot Tub Weigh?
When it comes to the weight of a hot tub, there's no single hot tub weight. The weight of a hot tub can vary depending on several factors, and these factors include the following:
The material used in constructing a hot tub can influence its weight. Hot tubs are usually made from a combination of different materials, and these materials affect weight differently.
Here's a summary of the weight of a midsize (4-person) hot tub with respect to the material it is made of:
Type of Material
Weight Without Water
Below 100 pounds
It is important to note that the weight of a hot tub will increase or decrease depending on the size of the hot tub.
In addition to the material the hot tub is made from, size is also a factor that can affect the weight of a hot tub. Hot tubs are built in different sizes and shapes to appeal to multiple customers. Hot tubs are generally grouped into three based on size, and these groups are small, medium, and large.
The size of a hot tub is determined by the dimension of the hot tub and the number of people it can hold.
Dimension of a hot tub
The dimension of a hot tub not only influences the space it'd take but also the weight of the hot tub. Below is a table to show you the average weight of a hot tub with respect to its dimension:
Size of Hot tub
Average Weight When Empty
5 to 7′
5 – 6'8″
300 to 500 pounds
6 to 7'10"
6 to 7'9″
600 to 700 pounds
7 to 9′
7 to 9′
800 to 1,000 pounds
Number of Occupants
A small hot tub can hold 2 to 4 people, a midsize hot tub can hold 5 to 7 people, and a large hot tub can hold 8 people or even more.
What Weight Does Water Add to a Hot Tub?
As shown above, size and materials are the main factors that determine the weight of an empty hot tub. However, this weight changes dramatically as water is added to the hot tub. When planning for the hot tub's foundation, it is important to consider the final weight of the hot tub to ensure that it is properly supported even when filled with water.
Water weighs around 8.5 pounds per gallon, which explains the significant increase in weight when water is added to a hot tub. Also, larger hot tubs can contain more water and will ultimately weigh more.
The table below shows the weight of a hot tub when empty and when with water for different materials.
Type of Material
Weight Without Water
Weight With Water
Below 100 pounds
Determining the Type of Foundation to Support Your Hot Tub
Since a hot tub that is filled with water can weigh over 3,000 pounds, excluding the individual weight of the people in the hot tub, determining the foundation to support the hot tub is of the essence. This is to ensure that the hot tub doesn't damage the foundation or even sink into the ground.
The common types of foundations to use include:
This is the best option to use as support for your hot tub. The recommended thickness for the concrete should be nothing less than 4 inches, with the base being around 6 inches. I always recommend a concrete base for a hot tub, if possible.
Decking is also a suitable choice, especially if you don't want to use concrete. A deck can provide support for your hot tub, but you must ensure that it is at least a foot off the ground. Increasing the height of the deck can also cause it to become unstable and may require reinforcements.
Ensure that the deck is strong enough to support the weight of the hot tub, including water, and the maximum number of people. Multiply that number with 2. So you are sure that when people are standing close, snow, or other equipment that you do not damage the deck.
– Pavers Bricks
This is similar to concrete and also a good choice for your hot tub's foundation. For this, the base needs to be six inches to make it sturdy. The materials at the base may include crushed rock, pea gravel, and sand. In some cases, a hot tub may be directly installed on gravel without using paver bricks.
– Spa Pad
This type of foundation is made of interlocking plastic squares, and it can be a great support for hot tubs. However, the hot tub must be at least 100 pounds per square foot.
Frequently Asked Questions
Here are answers to some frequently asked questions:
– What does a 2 person hot tub weigh?
Two-person hot tubs are small hot tubs designed mostly for couples. They are the lightest and weigh 300 to 600 pounds when empty and up to 3,000 pounds when filled with water. However, this also depends on the material the hot tub is made of.
– What does a 4 person hot tub weigh?
Four-person hot tubs are medium-sized, and they weigh 700-800 pounds when empty and 3,700 pounds when filled with water. The material used in making the hot tub also influences the weight of the hot tub.
– What does a 6 person hot tub weigh?
The approximate weight of a 6 person hot tub when empty is 1,000 pounds and 6,000 pounds when it is filled with water.
– What does an 8 person hot tub weigh?
Most 8 person hot tubs also weigh up to 1,000 pounds when empty and 6,000 pounds or more when filled with water. The overall weight depends also depends on the material used in making the hot tub.
– Will a standard deck hold a hot tub?
It is completely possible for a deck to hold a hot tub. Most decks are already designed to hold hot tubs, including standard decks. Also, decks that can hold up to 100 pounds per square foot will easily hold any type of hot tub. Decks that are designed to only support 50 pounds per square foot may not be the best support for some hot tubs.
– How do you reinforce a deck for a hot tub?
If you're planning to construct a new deck for your hot tub, you'll need to know the weight that the deck can support. The weight depends on different factors, including the footing size, joist overhang, soil type, and joist spacing. You'll also need to determine the weight of the hot tub, especially when it is filled with water and people. Ensure that you include the maximum number of hot tub users and a safety margin.
You have nothing to worry about if you already have a deck installed, even if it may not support the weight of your hot tub. You can modify or reinforce the deck support to allow it to hold a new hot tub. There are several ways to reinforce an already installed deck, but here are here methods to try:
Add a Beam
You can either add a beam and a ledger or a beam between the existing beams. This is also a lot easier compared to adding a post to an existing beam. Adding a beam involves removing the deck boards, installing patio stones with deck blocks above them, working the joists, and installing screw piles. If you're ready to go through the stress of digging, adding a post will be a better option for you.
Add a Post
Another way to reinforce a deck is by adding a post to the already installed beam. However, this is tricky because it requires going below the beam, and you might not be ready to start digging. Digging is generally uncomfortable because you may need to go 5′ into the ground. This is the main reason why a lot of people prefer adding a beam to reinforce their deck.
Alternatively, you can level the earth below your existing beam for a deck block, adjustable post, or patio slab. It is important to note that this won't give the same support you'll get when you add a new beam, but will only increase the deck's carrying capacity and reduce the load on the deck.