Can You Put a Hot Tub on Grass or on the Ground?

If you are thinking about getting a hot tub then you might well be wondering if you can just put it on the grass or on the ground or do you need to have any special surface or platform to stand it on? It’s a good question and you will find out everything you need to know about planning where your hot tub could stand in this post.

So, can you put a hot tub on the grass or on the ground? A hot tub has to be on a firm foundation and grass or the ground is not suitable. You need to have a concrete, brick or solid level base to support the weight properly. An inflatable hot tub can be temporarily put just on grass or the ground.

What sort of base does a hot tub need?

Hot tubs are extremely heavy objects even without the 500 or so gallons of water that they could potentially hold. The 500 gallons of water alone weighs the best part of 2000 KG and if you add to this the weight of the hot tub itself not to mention the weight of the occupants you can really see how the weight starts to add up.

So, it’s important to have an extremely strong and supportive base that won’t move or break up under the strain of the weight of the hot tub. This strength is necessary because the huge weight of the hot tub is also concentrated over a relatively small area. The 2000 – 3000 KG load could be all directed upon a footprint possibly as small as 8 feet square.

Now obviously a grass or earth base could take this amount of weight but the likelihood of it being completely level and not moving under the strain of the load is quite remote. The problem with the base moving is that it could then potentially put a great deal of stress on the hot tub frame and even the shell itself and once full of water and supporting the weight of the water the chances of the shell cracking or warping becomes increased.

What are the best bases for a hot tub?

So, we have already established that grass or just the ground isn’t a good base to put your hot tub on so, what is? Let’s have a look at some popular options.

Terrace/patio – You might already have an appropriate terrace or patio to put your hot tub on, in which case it’s job done! The patio will need to be well laid, secure and level though and have a good foundation. A lot of basic garden terraces/patios are laid very simply on sharp sand and secured with a few blobs of cement.

There’s nothing wrong with this approach as if you are only going to be sitting on the patio or putting a few plants on it this method works really well. However, a terrace/patio laid just on sharp sand will most probably not be stable enough to hold the weight of a full hot tub. The chances are that the patio slabs will move under the weight or possible crack leading to all sorts of issues.

If you are going to put your hot tub on a patio/terrace make sure that it has firm foundations. Ideally, there should be a hardcore base which will ensure greater strength and resistance to the weight. Any tiles or slabs should be thick and firmly cemented into place as well as being completely level.

Concrete slab – A concrete slab isn’t the most glamorous of solutions but is probably the best in terms of strength and security. The concrete needs to be at least 6 inches thick and preferably reinforced with steel. This is within the scope of a capable DIY project and isn’t too expensive to accomplish.

In terms of size, the concrete base needs to be larger than the footprint of the hot tub by several inches all around. It will also most probably be raised above ground level so you then need to consider how you will blend it into it’s surroundings – you might build up a deck around it or possibly create a larger concrete base and then tile the surrounding area. It could also form the basis of a raised patio or terrace.

Decking – Decking is a really popular option but you need to be aware that an average deck will not be built to withstand the weight of a hot tub. You have two choices: The first is to stand the hot tub on the deck anyway but to completely reinforce the deck below or the second is to build a concrete slab or brick and mortar support beneath, stand the hot tub safely on that and then build or rebuild the deck around it.

If you want to try to reinforce the actual deck then you may well need to get expert advice on exactly how to do this. It would be possible to use larger supporting wooden joists and to reinforce joints etc but you would also need to consider the foundations of the deck and whether they would support the additional weight as well.

I’m sure that it would be possible to achieve but my sense is that it would be a safer long term bet to build a solid concrete/brick base beneath the hot tub and then to deck around it. If you do that you can be sure that the hot tub is sitting on the most secure foundation possible and the deck is only supporting the relatively lightweight of people sitting and walking around the hot tub.

Hot tub pads – Hot tub pads are a relatively recent trend and are probably the best solution for anyone who hasn’t already got a suitable base or doesn’t want the effort and permanence of creating a concrete or brick and mortar base.

Hot tub pads are interlocking tiles which contain cavities that can be filled with gravel or pea shingle. To start you need to dig out a shallow and completely level area in the ground and then lay and interlock the right amount of tiles to stand the hot tub on with a little extra space around the edges.

Once you have done this the pea shingle or gravel is filled in and compacted and this gives a strong, level and firm base but with the added advantage of it being relatively easily moved and relocated, unlike concrete or bricks.

Alternatively, a pad like this one on Amazon will also do a good job, will hold up to 300lbs of pressure per square foot and is simple to install.

Related Questions:

How much space do you need for a hot tub? – Hot tubs come in all sorts of shapes and sizes so it’s difficult to say exactly how much space you will need. However, once you have chosen your hot tub you will need to allow space for the hot tub’s footprint plus at least a foot of space all round to allow access for maintenance. A small hot tub may take up as little room as a six-foot square footprint and would only need an eight-foot square base but many hot tubs are larger than this. Check out more details in my post here.

Where is the best place to put a hot tub in the garden? You will need a private and sheltered spot in the garden for your hot tub. Preferably it will be fairly close to the house for easy access and well away from any prevailing winds or cold draughts.

If you live in an extremely hot climate you might well want to put the hot tub in an area of shade but most people will want to have it in a sheltered sunny spot. Remember that you will need an electrical connection as well as a hose long enough to reach from the tap to your hot tub to fill it up.

Summary:

Unfortunately, you can’t put a hot tub onto grass or straight onto the ground as it is far too heavy and will possibly start to sink. At the very least the hot tub won’t be supported properly and this will potentially put excessive strain on the shell and could lead to serious damage. A hot tub should always be placed on a solid, level secure base such as concrete, a patio or terrace, a brick and mortar base or a well-installed and level hot tub pad.