Niels DIY Hot Tub Build – The Netherlands

Niels first got in touch with me in January 2022 about the possibility of me designing his DIY Hot Tub. Of course, the answer was yes.

What Niels was looking to build was a hexagon shaped hot tub. The challenge that he had was that he wasn’t sure on the plumbing side of things and also, the parts availability in The Netherlands was not great. Don’t worry I said, I can export everything you need and sort you out with a plan and a a design.

What is also unique about Niels plan was that he wanted to include a fire pit to heat. Having done one project like this with a customer in South America, I knew wheat we needed to do.

Let the design commence

As is normal on any of my custom design projects, we go back and forth with the design until the customer, in this case Niels, was totally happy with the design. 

From there, it is onto the plumbing layout which tends to be less backwards and forwards and I tend to put these together with little to no involvement of the customer, apart from control room location of course.

Parts Shipped

Fast forward 6 weeks or so after the design was complete and Niels was ready to get the parts ordered – so I exported everything that he needed to him in the Netherlands.

All Gone Quiet

When I first started doing these projects, what feels like a lifetime ago, I always used to get worried with things went quiet and I didn’t hear from a customer. Now, I just know “that’s life” and things happen along the way with these builds – it has become normal.

So, I thought nothing of it when I didn’t hear from Niels for some time.

Fast Forward to August 2023

Niels got back in touch and sent me a lovely email update – I am going to share some of it with you below.

For me it is, don’t know where you live so it might be good morning, afternoon or even night. What should have been an approximately 6 month project turned into a project over a few years. I remeber contacting you in late 2021, and here we are in 2023 and still not done. I’m making progress now and i’m committed to get it done now in a few weeks but probably a few months now.

I’m going to add a wetransfer link down in the bottom with pictures and give you some extra information of what happened where i stand now and how i plan to do a few things. It would be great if you could asure me of what i’m trying to do is right.

So here begins my story 

As you may know i’m what of a water pool enthousiast which is why i contacted you. We ( my wife and i ) bought a home which was actioned, but the previous owners left a prebuild jackuzzi. This was broken so i bought some pvc pipe and a wooden heater. I already did some experimenting on pools and heaters when i lived with my parents. So my whole live i’ve been a little obessed with swimming pools and huttubs, i even built a DIY sun heater for a stander intex pool.

Ok now to the part where we connected. I contacted you becouse the previous prebuild jackuzzi was broken and leaking from places i couldn’t reach. It wasn’t beatiful so my wife insisted on removing it and throwing it away. I said ok but just so you know there will be a new one. And i’m going to build it myself. She agreed not thinking ( i think ) i would actually do it. So after some e-mailing between you and me i had a picture of how i was going to do it.

So i started to dig a hole in the ground which would cover the hottub plus a bit to spare becouse we have to fit the insulation and plumbing (pictures -3, -4, -5 and 1). At foto 1 you can see how deep i dug and where our ground water level is at. On top of this i threw 17,5 cm of rubble grit ( pictures 2-4 ). After that i wanted to insulate my tub, my wife her cousin owns one of the biggest insulation companies in the Netherlands (3 biggest (isolatienoord)) and i asked him for some advise of which insulation i could use, with the possibility of getting wet. I don’t expect it to be but just to be sure. He asured me to use PIR plates which of course i did (pictures 5-8). I used 8 cm plates by the way. After that i threw a base of 17.5 cm concreet on top and with that my base was completed. If you look closely to the foto names you can see a date of when i took the pictures. So the “shovel” was put in the ground at 2 april. Then i did the rubble grit and insulation myself.

And here we have our first “wait moment”. My brother in law (which is also in the picture) is renovating his house. Point being if we ordered the concrete together this would save us a huge amount on the concrete costs. When we poured it was 28 of july. Which already made a delay of 3 months. And at this point my wife and i had just discovered there was a little baby on the way. So when the concrete was poured, we discussed we should put a halt on the hottub becouse we didn’t know which costs where coming our way and which were still to be paid for the hottub.

So then it became 25 of februari we were celibrating my birthday (which is 25 of februari) my wife her water broke and we had to go to the hospital, then 3.5 hours later our little wonder Eline was born. So you can imagine our life became a little hectic at that point. Now after all the dust settled down and things started to look like normal i picted up where i left off.

My father in law said he would help me with building the blocks back in summer of 2022. All that came but not my father in law becouse he prioritized my brother in law his new house and the renovation that came along with it. Which is of course totally understandable. So i asked a friend if maybe he would help me, and he said ofcourse you build my computer so i will help you build your hottub. So we got together on 2 saterdays, the first we build the first layer of bricks onto mortar so we had a level first base. And the second saterday we did the second and third layer (pictures 9-15). Then i had a little wait becouse it was a little hectic at work and i had to do some (a lot) of overtime hit our deadlines.

Which brings me to today. I have vacation now (5 weeks of which 1 already has passed). And i’m planning to do a work vacation as they call it. try to get as much done in and around the house so i can start clean when i have to start work again.

Yesterday and today i dug the whole which will be the compartment where the pumps etc. will be, you can see our little friend (Nora) is helping me dug out this place(pictures 16-19). After i kind of leveled the base of this i put in some leftover tiles, i will be adding 10cm of concrete here to bring it a little bit up. You can see i have a pvc pipe in place which will act as a overlow. If any or ever something will leak the water has a place to go. It’s connected to our local rainwater disposal network.

So, as you can see, this has been quite the journey already for Niels, but progress is being made. Do check back soon for an update on this project.


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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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