Custom Designed Hot Tub – The Process Explained

Custom Designed Hot Tub

Custom designed hot tub? In this article, I will explain exactly what the process is for those of you that opt to go down this route.

This is the process that most of the case studies on the website have followed.

Building a custom designed hot tub can be a daunting process. The whole rationale behind this website has been that when I built my own tub, I just couldn’t find the information that I needed.

I vowed that when I had finished my own custom designed hot tub, I was going to put all the information together into a website to help others. That is exactly what I have done here.

Now, I am helping people just like you with their own custom designed hot tubs.

“Off the shelf” Hot Tub Designs

You may or may not have already seen that in my online shop, there are lots and lots of “off the shelf” designs as I call them. I have recreated my own Hot Tub in several different sizes. I have cylindrical hot tubs in several different sizes and then there are some infinity hot tubs again in several different sizes.

However, you may be looking for something that is not really “off the shelf” in terms of the design. You have an idea in your head and you would like some help in making this a reality. This is where the custom designed hot tub process kicks in.

What is the custom designed hot tub process?

All custom designed hot tubs start with a rough sketch. This is the first thing that I would need from you.

The sketch will cover the size and layout that you are looking for. At this point, I will also need to know how you are going to build your tub. Poured concrete or block built?

This is also the time to tell me about any water features you are looking for. How many jets you are thinking and if there is anything else that you have on your mind that would be pertinent to the design.

What about the control room?

If you have had a read around the website, or watched any of my videos on my YouTube Channel, then you will know that the control room is kind of key.

I am not going to go through the whole process in this article as I already have an in depth article here about the control room. However, I will need to know if it is above or below the water line and also how far it is going to be away from the hot tub.

This will dictate the type of pumps needed as well as working out the size of pump after a calculation of head height has been done.

Photos or Video of the proposed site for your custom designed hot tub

Accompanying your sketches of the custom designed hot tub with a video of the proposed location and also some phots is a great idea.

This gives me plenty of insight to where you are planning the tub and how it should look and fit in with the location.

I can also help to spot any potential problems with the site too.

Time for a Scope of Work Document & Accompanying Invoice

At this point it is time to put exactly what you are going to be getting into a scope of work document. This document lays out the specification of the design. For example, the hot tub will be based about this sketch, comprise of 10 jets and a waterfall. The scope of work also details the deliverables in terms of the documentation that you will receive at the end.

Upon signing of the scope of work document, I will then issue you an invoice for the design fee.

3D Modelling of your Custom Designed Hot Tub

The 3D model really helps your ideas come alive. This is an interactive process so you get lots of email or WhatsApps from me with screen grabs of the design. We take this back and forth as many times as is needed to get this complete.

Once you have “signed off” on the 3D model, it is then time to add the plumbing to the model.

Plumbing layout of your Custom Designed Hot Tub

The plumbing design is less of an “interactive” process as really most of the plumbing is set by rules and precedent.

What the 3D plumbing layout does for you is give you a way to visualise and see exactly what is going to fit where within the design.

Understanding how the tub works is really important and the 3D plumbing layout will certainly help you do that.

Architectural CAD

Once we have the 3D layout and the plumbing, then the design goes off to the CAD/Structural engineers to then produce the dimensional architectural drawing.

If you are using a general building contractor then this is the drawing that they will be looking for. They don’t want to trawl through a 6000 word document, they want a single page to show them what they should be building.

Documentation and Parts Quotation

The final stage of the process is to put together the documentation for your project. This includes around 6000 words explaining everything to sealing concrete to insulation.

This is a document that I have built up over the last few years and really delves into the depths of all things DIY hot tub. If it is not in there, it is probably not needed. Bold statement? Perhaps, but this is a tried and tested document and has been used to build literally hundreds of tubs.

If there is something missing, then let me know and I will certainly add it. Having the best and most comprehensive documentation is important to me.

The Process In a Nutshell

  1. Rough sketch of the tub with external dimensions
  2. Details of any features eg water falls that you are looking for
  3. Position of the control room
  4. Photos and video of the site
  5. Scope of work
  6. Invoice
  7. 3D modelling of the tub
  8. Plumbing Layout
  9. Architectural CAD
  10. Comprehensive documentation
  11. Parts Quotation

If I can help you in any way with your own DIY hot tub, then please do get in touch using the form below.

Happy Hot Tubbin’

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi


Hi, Andi here. I own and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 1000 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi

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