Niel contacted in early August 2020 after he had been following the instructions for how to build your own DIY Hot Tub. Niel is a competent DIY’er – you’ll see some of his pictures below and the block and brickwork as well as his concrete slab were very well made indeed. He certainly didn’t need any help with this side of things! Niel contacted us because he was a little unsure on the plumbing side of the build.

He had been following the brickwork and ground prep that we describe in the “How To” page that Andi wrote. What Niel couldn’t get his head around was the plumbing side of things. Instead of making some costly mistakes, Niel got in touch.

Initial Contact

Niel made contact with Andi over the online chat on initially to thank him for all the info that he has put on the site. The pair began to chat and Andi answered some of Niel’s initial questions. He then offered to draw up the plumbing plans for Niel when they identified that this was the area Niel was struggling with.

It wasn’t just the plumbing diagrams that Andi helped with, he converted Niel’s PowerPoint sketches into full 3D modelled CAD. This then enabled Niel to visualise the build a little bit better. On the back of this, he also changed the design slightly and moved the step positions.

The 3D model also helped with discussions on where jets were going to go, light placement – things that were just a bit too difficult to visualise from the powerpoint sketch.

Scope of Work

The scope of work for Andi and is the custom design of the hot tub, plus full plumbing diagrams for Niel as well as supplying the plumbing parts.

Early August 2020

This is very much the “before” shot of Niel’s garden.

The mini digger made light work of digging the hole and clearing the area – much easier than the back=breaking way Andi dug his!

A bed of type 1 was “whacked” flat

The base was lined and then filled with metal rebar for additional strength. Beautiful work here Niel!

The slab was then poured.

September 2020

A retaining wall was put in but then Niel hit a little bit of a roadblock!

The dividing wall with his neighbour was too weak and was beginning to crumble. With a young family, it was just not worth taking the chance so Niel has had to put development on the Tub on hold whilst he pulls back and rebuilds the wall first!

October 2020 – Just Call Him “Mr Blockwork”

The last few weeks have really seen the weather turn in the UK. It was as if someone had flicked a switch. We went from sun and pleasant temperatures to rain and chill overnight! So now, Niel has the UK weather to contend with as well. Needless to say, progress on Niel’s build has been slow. I mean, how are he take a couple of weeks off to go on a family vacation! Hope a good time was had by all!

Anyway, back to the build and “Mr Blockwork” is back in action repairing the boundary wall between him and his neighbour. If that job in finance goes down the pan, you’ll have no problem as a bricky! Once again, stunning work Niel and this one is certainly not going to fall down – just take a look at the beautifully made foundations! Niel plans to clad and tile this one the tub is in place and I am sure it is going to look fantastic.

Looking good Niel, mind your step!

November – December 2020

After completing the external clockwork and putting in the lower block work for the seating, it was time for Niel to bore some holes. As you can see from the pictures, Niel invested in a pretty heavy duty hammer drill along with some core-drill bits. I think he said he got a good deal on them on Black Friday. They certainly look the part.

The next task for Niel is to core out all of the holes for the lower drains and also the gunite bodies.

With the weather taking a turn for the worst this time of year, progress is slow. The Christmas holidays were upon Niel in no time but with a young family, there are more important things to do this time of year than to be boring holes in cinder blocks!

January 2021

After a very cold and wet Christmas break, Neil has picked things up again but progress is slow due to the weather. Niel has drilled the holes for the gunite bodies and then threaded through the 2.5″ outer pipe from outside of the tub into the footwell for his lower jets.

To try and reduce the heat loss, he is going to insulate the seating area with celotex insulation.

With a bit of luck, this will help reduce the amount of heat lost and in turn, allow Niel to make some savings on the running costs.

Finally, Niel has backfilled the seating area. You will see that he has changed his design a little in that now, there is seating just on three sides. This is because his wife wanted to have more space for his young family to learn how to swim in the Hot Tub – how cool is that!

Keep up the good work Niel, this is coming along nicely!

May 2021

Niel says himself this this was never intended to be the fastest of builds, but the quality that Niel is producing is fantastic. The next stage for Niel was a water proof coat onto the interior walls of the tub. Niel opted for quite an expensive materiel called Ardex S7. Once this was painted on left to dry, the interior would be totally sealed, even before tiles were applied.

June 2021

Next, it was time for a water test. This is not something that everyone does, but Niel being the pragmatist, meant that he was not going to miss this out. He also confirmed that there were no leaks! Awesome job Niel.

Niel has now built up the exterior walls that cover the pipework and insulation. Certainly starting to look the part.

September 2021

Niel is now at the stage where he is tiling his tub. The water tests all went well so he is now on the finishing straight to getting that tub up and running! How good does this look?

Time for Some Tiles….

With the coping tiles in place, it is time for Niel to put on his mosaic swimming pool times. Niel has opted for an epoxy grout for some extra waterproofing of his structure.

I absolutely love the colour that Niel has chosen. It is looks absolutely superb especially when you offset it with the tiles on the back wall.

As always, with everything that Niel does, the workmanship is just sublime. The sun is just bouncing off the iridescent mosaics and looks fantastic. One of the advantages of the swimming pool tiles is the cornering that you can get You can see how Niel has created a lovely curve over the seat which is just not possible with regular tiles. It also does away with the need for a corner strip (which I used on my own build)

Next up for Niel, fitting the light that he purchased from

Fitting the Hot Tub Light

The last piece of this DIY Hot Tub puzzle was to fit the light that Niel purchased from He has very kindly send me a video that I will be editing and adding to the YouTube channel very soon.

The light itself is a surface mount. There is a small niche that needs to sit inside a length of pipe and then the cables can either be run out of the back and sealed or run through conduit up and over the water line which is totally fine too. The light is then secured in place with two fixing screws, really simple to do but being super slim gives a very nice look to the Hot Tub.

Project Complete – October 2021


What a project! In the end, Niel opted for a 3KW heater with a secondary 3KW slave or auxiliary heater. 16 jets, running on a Balboa Spa Pack. The auxiliary heater makes all the difference as he said that it was heating at around 2-2.5 C an hour and that is without a cover as he has not sorted one of those yet. In comparison, my own does around 0.5-1C an hour WITH a cover so it a big difference.

In terms of cost, all said and done for Niel it was £6200 ($8500) and he doesn’t mind me sharing that with you!

It’s at this point in any project, I can’t help feeling a sense of pride. Whilst Niel has most certainly done all the work himself and what a job he has done. Once again, I’ve helped someone build and achieve exactly what they set out to do – their own DIY Hot Tub.

When Niel sent me the picture over WhatsApp of him in his tub, honestly, I had as big of a smile on my face as he did. I was quite emotional to be honest!

Some customers I have little to no interaction with. Others, I exchange a lot of correspondence and Niel was one of these. It seems like I have been exchanging messages with Niel on this project for forever. About 18 months from start to finish. Niel’s philosophy has always been to take his time over every stage of the project.

He had no intention of rushing anything and it think this really is testament to his workmanship. We can all certainly take a leaf out of his book on the not rushing side of things!

The finished project is just amazing.

Hat off to you Niel, really well done my friend.

Enjoy the tub with your family. Project Complete!

Happy Hot Tubbin’


Do You Need Some Help with your DIY Build?

If you need some help with your build then let us know. Drop us an email at or use the chat. We can help with plumbing designs. We can supply the specialist parts that you need. We can even convert your sketches into 3D CAD so you can better visualise what you are trying to build. Take a look at our plan options here.

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


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