DIY Hot Tub Case Study – Marc from the UK

Marc's DIY Hot Tub



Marc contacted in May 2021 as he wanted to build a hot tub between the area in his house and the garage. On Day Zero video below, you can see Marc showing the area where he had been using an inflatable tub for quite some time. He had a lazy spa which he had been having issues with for 16 or 18 months, it was repaired several times in the last 12 months alone. He spent a lot of money – nearly £3000 / $4000 – on repairs for it, and he still didn’t have a working hot tub!

So, he started searching for a solution and eventually found Andi from Andi had assured Marc that he could fit a hot tub in that space – which was not a regular shape and more of a pizza slice. First things first, Marc needed a design.

Marc Hot Tub Design

Initial Contact

After finding, Andi and Marc had a chat on the design and a scope of work document was drawn up. Emails were exchanged for the design until Marc was happy with the layout. 

On Day Zero, Marc was going to start ripping out all the remains of the old hot tub and start digging for a new one. The new tub was going to replace an old, inflatable hot tub that burst, and he couldn’t repair or repaired it so many times that he had given up.

It was time to for Marc to dig the hole! Check out the video below and we can see that Marc is sending us an update of his progress.

Early May 2021 

On day 5, which happened to be a long  holiday weekend, Marc started digging. He wanted to dig as much as possible during the holiday. He found it very hard because it was compacted stone. So, he ended up getting a digger which managed to take out quite a lot of the stone.

However, unfortunately, it was still a little less than what he was hoping for: he wanted to go down deeper. So, Marc returned to the back breaking digging and dug some more out to get down to the level that he needed for the base.

Two Weeks In……

Two weeks in, Marc had the slab in. He just started to put his corners in of his block work, where he’s going up two courses, then he’s going to pause and then put in the low-level holes for the pipework. As  he has such a tight void, if he builds a whole lot, he will struggle to get down to the pipework level so needs to do that before he goes too high with the blocks.

But it was going well, though slab was a little bit of a nightmare. It took him from 8:00 am to 10:30 pm, and it still wasn’t level!

Next goal, he is hoping that by the weekend, he should have the first two rows in and the seats ready to start the first part of the plumbing.


8 Weeks in

After 8 weeks of labour, Marc was halfway through his hot tub build. It was time for him to get the low-level plumbing in. He had not got a lot of room down the sides, meaning it was not possible to do the low-level plumbing until it was fully built. There was a step, and the skimmer and plumbing could be seen coming from the garage.

By now, Marc was already done with the main control room in his garage. He had put his control room on a board that was on wheels, making it easier to put it out if needed.

Marc was happy and ready to get his electricity supply ready to connect in.

He had been enjoying the build and was grateful for the assistance he has been receiving from Andi at

12 Weeks In

After 12 weeks and under the guidance ofAndi, Marc was able to reach the state where he now has bricks in place, and is starting to look like a hot tub.

The next step was to put in the plumbing, and it was the plumbing Marc really wanted the most help with. He found those designs that he got from really easy to follow.

You can see in the video that not everything is straight forward with the plumbing. Some of the fittings are very tight and very close together because it was in a  confined space. So, making some of the pipes and the connection was quite difficult. But as you can see, Marc managed to do a fantastic job from it. By this stage, he is almost done with all the plumbing work.

What’s next? It’s time to put in the insulation. You can see in the video that he has used some Celotex insulated boards that he dropped down the sides right next to his plumbing, and that helps increase the R (insulation) value of the tub, and hopefully, it will cost him a lot less to run than not having insulation.

Almost There

Next steps for Marc is the tiles. The weather is changing and he has a lot of work on at the moment so this may slow things down for Marc. It does look fantastic though, great work Marc and we look forward to the next video update.

Marc's DIY Hot Tub


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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