Can You Put An Inflatable Hot Tub On Decking?

Can you put an inflatable hot tub on decking?

The answer is yes; however, when planning where to put your hot tub, there are a few things you’ll need to consider. One is the weight of the tub when it’s full of water and people. 

We’ve been reviewing and testing inflatable hot tubs for years, so we know a thing or two about where and where not to position them. 

Inflatable hot tubs for 4-6 people can weigh up to 4000 lbs, so you might need to build a concrete base and construct decking around it unless you have a reinforced deck. 

Another thing to consider is the longevity of your decking; You might want to think about putting your inflatable hot tub on a concrete pad or another surface that will last longer.

Finally, you’ll need to take into account the height of your deck. Decks up to 2 feet off the ground can usually support 100lbs per square foot, but you’ll need to factor in additional support if your deck is higher. 

With all of these considerations in mind, you should be able to find the perfect spot for your new inflatable hot tub and your deck may just be the ideal spot! 

Can A Hot Tub Sit On Decking?

decking with table and chairs on it

You can put inflatable hot tubs on a wooden deck; however, it’s essential to ask whether your deck will hold the tub’s weight? 

Deck requirements for a hot tub

Ground-level decking can support up to 100lbs per square foot, whereas raised deck boards can only support about half that weight. 

So you may get away with placing a smaller inflatable hot tub on a raised platform, but a family-sized inflatable hot tub will almost certainly be too heavy. 

How Do I Know If My Deck Can Hold A Hot Tub?

wooden decking starting to lift up

There are a few things that contribute to how heavy your inflatable hot tub is: 

  1. Obviously, size is the major one. The larger the tub generally, the more water it will hold and the more it will weigh; even empty, a 4-6 seater hot tub can weigh over 100lbs
  2. The type of material your inflatable hot tub is constructed from can also impact how much it weighs. It stands to reason that an inflatable hot tub which is made from vinyl or PVC is lighter than plastic or wood. 
  3. Water weighs 8.34lbs per gallon, so you can quickly figure out the weight by multiplying this by your hot tubs water capacity, which can be found on the packaging or your hot tubs brand’s official website. 

The average weight of an inflatable hot tub

We’ve manoeuvred a fair few hot tubs in the last decade and believe us when we say that whilst not as heavy as a permanent hot tub, most inflatable hot tubs weigh a lot. The average hot tub weighs about 60 -100 lbs when empty. 

However, a full inflatable hot tub can weigh upwards of 2,000 lbs and that’s without adding the weight of the bathers.

With all the different shapes and sizes available, generally, the larger the hot tub, the heavier it will weigh. The materials used for construction will also affect the inflatable hot tub’s weight.

Deck load calculator for a hot tub

Working out how much your spa tub weighs isn’t difficult. Below is how to do it: 

  1. Record how many litres your hot tub holds, for example, 930 litres 
  2. Multiply by 2.2; this will give you its weight in lbs (2,046)
  3. Add the approximate combined weight of bathers, say 3 x 10 stone which would be 140lbs. 
  4. This gives you a total of 2,146lbs which you then divide by the area of your hot tub’s base. 
  5. This will give you the spa’s weight in feet square. Ground decking can support up to 100lbs per square foot, whereas raised decking can only support about half that weight.

Alternatively, you could use a deck load calculator to calculate the weight distribution per square foot. 

We would suggest that If you are considering placing an inflatable tub on your existing deck, get a professional to take a look and, if needed, add extra structural support. 

Will I Need To Reinforce My Garden Decking?

two planks of wood being reinforced

Not surprisingly, when you think about how many gallons of water they hold, even inflatable hot tubs are heavy when at full capacity, so there’s a good chance the existing beams will require extra reinforcement to avoid the risk of structural failure. 

You never know; you might even decide to upgrade to a hard-shelled hot tub eventually, which would definitely require your deck to be strengthened. 

The age of your decking is important.

If you plan to install your hot tub on an existing deck, you need to consider the age of the structure. 

Not only may the materials be weathered, aged and unable to support a heavyweight, but the installation standards may be very different, which can impact the structure’s integrity. 

The good news is; that adding a few support beams or adding joists isn’t a huge job.

Should you hire a professional?

Unless you are a competent DIYer or professional joiner, we recommend leaving this job to an expert. They will be able to ascertain precisely how much weight your wooden deck can handle and advise what needs doing to provide additional support. 

How To Reinforce A Deck For A Hot Tub

decking being built with a drill on it

A deck needs to be able to support a hot tub or be reinforced, or you could risk structural failure. The good news is you don’t have to start again from scratch rebuilding the entire deck. 

Adding an additional beam between two existing beams will increase the total weight capacity of a wood deck, narrower joist spans and installing ledger board fasteners can also provide extra support for a hot tub. 

However, it really is a good idea to consult a qualified deck builder or professional carpenter who will be able to advise you of your options. 

Additional fasteners
Along with adding additional support posts, it’s advisable to add additional ledger board fasteners when you place a hot tub on a deck. Your deck depends on the load-bearing capacity of these bolts to prevent the deck from tearing away from the house. 

The added weight of an inflatable hot tub requires the support of at least an extra four ledger board fasteners for the deck. 

Extra joists
Adding extra joists is an excellent way to give extra support to those already under your wooden deck. 

All you need to do is ensure that they are installed underneath where the spa tub is going to be positioned on the deck and clamp them to the joists, which are already there. 

Joist hangers must always be used on decks with an inflatable hot tub as they provide long-lasting support, prevent the pressure-treated lumber from twisting or shifting and are much more versatile than traditional screws or nails.   

More beams in weight-bearing areas
If you decide to put an inflatable hot tub on ground-level decking, the timber for the deck can handle up to 100lbs per square foot. 

However, this decreases the higher your deck is, so maybe as little as 50lbs per square foot. This can easily be resolved by adding some extra beams underneath the deck to support the weight of the hot tub.  

Building A Deck Around The Tub

a sunken hot tub overlooking the sea

If you are building a new deck to put an inflatable hot tub on, a common practice is to first lay a concrete patio at ground level. 

The concrete surface is plenty strong enough to support the average weight of a Jacuzzi and the deck can then be constructed around it, giving the appearance of an in-ground hot tub. 

Remember, if you choose to build a deck around your inflatable hot tub, you need to ensure easy access to the side of your tub for maintenance and repairs. Hence, a good tip is to install a small removable decking section for accessibility.

Is Decking The Best Place For A Portable Hot Tub?

When you put an inflatable hot tub on decking, it certainly makes an impact, the wooden deck boards are comfortable for bare feet and usually, the decking is close to the house, meaning easy access to water and a power source. 

However, if you’ll be building a new deck from scratch, it’s one of the most expensive hot tub bases to construct. Because a deck is not solid, it amplifies the noise of an inflatable hot tub and It’s also the least durable base option. 

However, if you have an existing decked area less than two feet off the ground, it will more than likely support an inflatable hot tub and could be a convenient choice. 

Can you put an inflatable hot tub on composite decking? 

Is composite decking better than a wooden alternative for an inflatable hot tub? We would say yes, as it has a much longer lifespan, won’t be damaged by excess moisture, and is resistant to mould and algae. 

However, although much more robust, it still needs to be able to handle the weight of an inflatable hot tub, which means once again, it needs to be low to the ground, or it may need additional support.

Will Hot Tub Water Rot My Decking

rotten decking starting to come away

If you have pressure-treated timber, then a little splash of hot tub water won’t impact your deck. However, as with any lumber subjected to excessive moisture over long periods, this can cause a problem or maybe even a number of issues as it can cause it to split, rot and warp. So can hot tub water hurt your expensive decking? The answer is yes, eventually! 

If you are still unsure about what surface to use, see more advice on a hot tub being installed and what you should be using to support its weight.

Key Takeaways

  • A deck can be a suitable base for an inflatable hot tub, but it’s not as straightforward as just setting up the new hot tub and hoping for the best. You will need to establish if your decking can support the weight of a spa or hot tubs, even an inflatable one? 
  • Working out the weight of inflatable hot tubs isn’t as complicated as you may think. There are several simple mathematic equations like the one above to do it, or you could use an online calculator to uncover your deck’s load-bearing capacity. 
  • You can add extra support underneath your deck to support an inflatable hot tub relatively easily by adding more joists, additional fastenings and installing more beams, although we advise you to contact a professional to ensure this is done correctly. 
  • The best way to incorporate an inflatable hot tub into your decking is to sit the tub on a concrete pad or one of the many synthetic tub pads and construct the decking around it; this way, you get the best of both worlds.

Last Word

a hot tub on decking with snow all around it

Still on the fence about whether to sit your inflatable hot tub on decking? It is an option, but there are extra considerations compared to other base options, primarily the significant amount of excess weight putting hot tubs on a deck creates. 

The higher the deck is, the less weight it can hold and even an empty inflatable hot tub weighs a fair bit, so be sure to check the manufacturer’s specs and be extra careful if your decking is old, as it could be starting to rot. 

That being said, you can put an inflatable hot tub on your deck if you are willing to provide some extra support in the form of extra joists and additional ledger board fastenings to strengthen the structure. 

As we’ve touched on above, you can efficiently work out your inflatable hot tub model’s exact weight, enabling you to determine if the deck is strong enough to support it. If not, you should consult a qualified tradesman who will be able to advise you on the best course of action.

We hope you’ve found this article helpful and if you have decided to go ahead and have your inflatable hot tub on a deck, good luck and happy soaking! 

John Devlin

Hello, Welcome to my website. I’m John, and I created the InflatableHotTubGuide while researching these spas nearly a decade ago. Since its creation, the site has become the leading UK resource for many models. As a passionate hot tub user, I love to test and explore all the latest machines this industry keeps creating. I hope you find our content helpful.