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Hot Tub Construction

Mar 9, 2018 | Building or Buying a Hot Tub

With any type of project whether it’s done through a professional contractor or if you are planning to do the building yourself, the first stage is always about the planning, Hot Tub Construction is no different. After all you wouldn’t take off on a trip unless you have a destination where you wanted to go, would you?

I’m going to guess that you’ve thought about building a hot tub or spa from time to time but weren’t sure you had the skills to do this type of project. Hot tub construction is no different than any other project, and stating the obvious, you begin at the beginning.

So what is the beginning you ask, well fortunately Custom Built Spas has put together a comprehensive and highly detailed spa and hot tub building manual that will coach you through the very first step right up to the last step of this type of project, no details left out. There is no information source or package that is as comprehensive as what is offered by Custom Built Spas.

But let’s take a few moments and look at what is going to be involved in a hot tub construction project. Now some of these things are very basic but sometimes it’s easy to over look the obvious and make assumptions that could get you in trouble later.

It’s not my intention to give you the entire outline of the hot tub construction process in this blog, however, I do want to give you enough information so that you can evaluate whether building a hot tub on your property is feasible.

While it might seem like it’s a simple process of throwing down a slab and building a hot tub on it, there’s a little more to those first steps than that.

Site selection is the first step I look at before any type of hot tub construction can be considered and here’s why. You’re going to need a certain amount of room for your hot tub and that will be dictated by how big you want it and how many people will be using it.

These sound like obvious common-sense factors to consider, but over the years I’ve found that common sense is not so common. So, its intended use will be one factor that determines size. Another obvious factor is available space and the last factor I look at but find is the most over looked factor is what is in the ground, if anything, under where you want to put your hot tub. You may be digging down some to put your hot tub in.

The last thing you want to run into is sewer lines, a septic system, water lines or underground electrical service or maybe gas service lines going to the house. Never build over any of these lines period!

Next, look up! What’s over or overhanging the area where you will be doing your hot tub construction? You definitely don’t want to be building under any power lines. Common sense right, yes but I’ve seen people do it, potentially very dangerous situation. If you’re near trees that if they were to fall would they damage your hot tub? It happens, so put some thought in your plan before choosing a location falling trees could be an issue.

One final consideration as to location is accessibility. If you are going to pour a concrete slab, does a cement delivery truck have access to get close enough to do the pour or will you have to use wheel barrows to get the concrete to the slab frame. The last resort on this is to buy a bunch of ready to mix concrete bags, mix and place the concrete in the frame work yourself. A little tedious but can be done, good exercise though.

Let’s talk about the basic slab a hot tub would be built on, it’s the most important part of your spa or hot tub construction project. Here are couple of pictures of what that will look like.

hot tub construction  hot tub concrete base

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Hot tub construction  hot tub construction

In each of the pictures shown above you see various pads for hot tub construction. A couple ready to pour, a few just poured, some in ground, partially inground and on the ground. All acceptable ways to do the base construction, but check building codes for your area.

The details are these. At least a 6” thick concrete slab using 3000lb or 3500lb concrete. In cold climate areas lay down a 1” or 2” layer of closed cell foam board under the hot tub area of the slab. (no it won’t cause the slab to crack). On top of the foam board or ground if you don’t put down foam board, put down a wire mesh layer. Install stand offs, the orange thingies, (center picture-right), then ½” steel rebar, crisscrossed and spaced 12” apart. You will also need to connect a bond wire to the rebar grid that will connect to electrical grounding.

Of course you want the forms for the slab level and squared, I cover how to do all that in detail in both my spa building books and my video, which is also part of my information package. Once the concrete slab is cured, give it a couple of days, you’ll be ready to go on to the next step of your hot tub construction project, building the walls. Another day for that blog or you can get all the rest of the information right here, right now delivered digitally, “instant access”.

Hope you got a lot out of the information in this blog and I hope you can see that this part of the hot tub construction process, the most important part, is not that difficult to do.

Visit, See some of the many projects my customers have done using my information and FREE help. The money I can save you can easily be hundreds of times more than the cost of my information package.

Thanks for the visit!

Gene Trumbull
Custom Built Spas

Call With Questions (860) 571-8440



Remember, my Mission is to help you, as my customer, build a beautiful hot tub of your own! I can show you how to build Spas, Hot Tubs, Swim Spas, Plunge Pools, Cocktail Pools or Exercise Pools at incredibly affordable prices! Everything you need to know is outlined in my series of easy-to-follow books and videos that cover a simple, step-by-step process that I’ve developed and refined over the years.

I will teach and help you with everything you need to know about building your own spa, hot tub, or swim spa yourself, regardless of what your DIY skill levels are and at a cost, YOU determine YOU can afford. As my customer, I’ll work with you at your own pace until your project is done and comes to life! For over 25 years now I’ve been helping people just like you, build their own hot tubs, spas, and swim spa projects. So, are you’re ready to let me help you build your project? Then what are you waiting for, let’s do this!

Custom Built Spas