DIY Hot Tub Kit: What’s Included and Which One You Need

Last updated: September 2026

If you’re looking for a DIY hot tub kit, chances are you’re planning to build your own hot tub. You’ve come to the right place. This blog and my YouTube channel are all about DIY hot tubs. I built my own, and I’ve since helped more than 1,500 people with their plans, designs and parts.

In this post I’ll go through what to think about before you buy a kit, what my kits include, and the right route for each type of tub.

What type of hot tub are you building?

The first thing to decide is the type of hot tub you’re building. Why? Because different materials need different parts.

If you’re building a stock tank hot tub from a metal or plastic stock tank (an animal feeder), you need very different parts from someone building a cinder block or poured concrete tub. The jets and the parts in the tub itself just aren’t interchangeable. You won’t use gunite jet bodies on a stock tank, because they don’t fit. Likewise, you absolutely need gunite bodies if you’re building in block, concrete or ICF. The control room equipment (pump, filter, spa pack) is similar either way.

What you’re building	What I’d buy	Guide
Stock tank hot tub	A complete stock tank hot tub plumbing kit	How to build the ultimate DIY stock tank hot tub
Cedar or wooden hot tub	A complete cedar/wood hot tub plumbing kit	How to build the ultimate DIY wooden hot tub
Block, ICF or concrete in-ground tub	Hot tub plans with a full parts list, or a custom design with a parts quotation	How to build a DIY in-ground hot tub
An existing tub or pool shell	A plumbing consultancy, with a parts specification and quotation	How does hot tub plumbing work?

My stock tank and cedar/wood hot tub kits

These are complete plumbing kits. The idea is “just add a tank (or tub) and pipe”. There are four versions of each:

Kit	Pump	Jets and air	Price
Heating and filtration only	0.25HP single speed	No jets. Two returns bring the hot water back in.	$1,399
4 jets	2HP dual speed	4 jets plus an air blower	$1,599
8 jets	2HP dual speed	8 jets plus an air blower	$1,699
16 jets	2HP dual speed	16 jets plus an air blower	$1,799

Every kit includes a Balboa 4kW spa pack with a topside control (the 3kW version for European supplies), a 25 sq ft cartridge filter, two lower drains, the valves, unions and fittings to put it together, a pump cable, and a guide. The jetted kits add the jets with their bodies and gaskets, the blower and an air check valve.

What’s not included: the tank or tub itself, PVC pipe and cement (buy those locally), and the hole saws. You’ll need a 65mm hole saw for the jets or returns and an 85mm one for the drains.

The stock tank kits:

• Stock tank kit, heating and filtration only
• Stock tank kit, 4 jets
• Stock tank kit, 8 jets
• Stock tank kit, 16 jets

The cedar/wood kits, which come with my wood/cedar hot tub plumbing guide:

• Cedar/wood kit, heating and filtration only
• Cedar/wood kit, 4 jets
• Cedar/wood kit, 8 jets
• Cedar/wood kit, 16 jets

These are proper spa parts, not a cheap and cheerful setup. The most important thing about a kit is that you know you have the right parts, and that if you follow the guide, the chances of your tub working at the end are high. They’re tried and tested, so you can sleep easy knowing you haven’t wasted money on kit that won’t do what you thought. And if you get stuck assembling it, I’m on hand to help.

For a real example, see Ben’s stock tank hot tub kit build in California, or adding a DIY stock tank hot tub to an Airbnb.

What features do you want?

The features you want decide which kit you need. If you only want a soaking tub with heat and filtration, don’t buy a kit with jets. Pretty straightforward, right?

If you want a water feature, like a waterfall, it doesn’t go on the same pump as your jets. It never does. You’ll need an additional pump, and I’m happy to help you work out what to add. See How many pumps do you need?

And if you’d like to control it from your phone, the ControlMySpa WiFi module from Balboa works with Balboa packs. Check that your pack is compatible first. There’s more in my ControlMySpa review.

Have you got a plan?

Having all the gear and no idea is exactly where you don’t want to be. Every kit comes with a guide. If you want more depth before you start, there’s also:

• The Ultimate Stock Tank Hot Tub DIY Guide, which has five plumbing diagrams, each with a bill of materials, from heating and filtration only up to 16 jets.
• The Stock Tank Hot Tub Control Room Guide and the Hot Tub Control Room Guide. They’re PDF guides to building the control room (no parts included).

What if you’re building an in-ground tub?

Here’s where I need to be clear. There isn’t an all-in-one kit for a block, ICF or poured concrete in-ground hot tub in my shop today. Every in-ground tub is sized differently, needs gunite jet bodies set into the walls, and has its own pipe runs. So instead of a box of parts, you start with a design that tells you exactly which parts you need:

• Standard sizes: my DIY hot tub plans ($149) include CAD drawings, plumbing diagrams, a detailed parts and materials shopping list, the build guide and the video course. That shopping list is effectively your kit list. See my DIY hot tub shopping list for what it covers.
• Your own layout: design it in the free Tub & Pool Designer Pro software, then I can turn it into architectural CAD and a 3D plumbing design, which includes a parts quotation.
• Something truly custom: my custom hot tub design consultancy finishes with a full parts quotation built around your 3D plumbing layout. See how the process works.
• Shell already built? The hot tub (or pool) plumbing consultancy gives you a 3D plumbing schematic and a parts specification and quotation, which you can order through parts4tubs.

Spa packs, pumps, blowers, filters and plumbing parts are available from parts4tubs.co.uk in the UK and parts4tubs.com in the USA. For the walls, ICF systems like TubBlox make building much easier. See How to install gunite jet bodies for the in-wall part.

Power and heating

All my kits use a Balboa spa pack with an electric heater: 4kW for US-style supplies, or 3kW for European ones. A spa pack like this needs its own dedicated circuit with RCD (UK) or GFCI (USA) protection and a local isolator or disconnect, fitted by a qualified electrician. It’s not a plug-in job. See Hot tub wiring explained.

Be realistic about heat-up times. As a rough guide, it takes about 1.16kWh to heat 1,000 litres by 1°C, so a 4kW heater raises a 1,300-litre (roughly 340-gallon) tank by around 2.5–3°C an hour before heat losses. From cold, that’s an overnight job, and a metal tank loses heat through its sides fast. Insulate and cover it. If you want lower running costs later, you can add an air source heat pump. See How to add an air source heat pump to your hot tub.

Why use a kit rather than buying parts one by one?

• The parts are matched. The pump, filter, spa pack and jets are chosen to work together.
• Nothing’s missing. All the fittings, unions and valves are there, so you’re not making five trips to the hardware store.
• There’s a guide showing how it goes together.
• There’s help if you get stuck assembling it.

Building your own tub is also where the real benefits come in: the tub is the size and style you want, you learn how it works (so maintenance and fixes are easier), and you use standard parts that can be repaired or replaced for years. For the honest pros and cons, see Pros and cons of building a hot tub, and for budget routes, What is the cheapest hot tub to build?

Common kit mistakes

• Buying before deciding the tub type. Stock tank jets won’t work in a block wall, and gunite bodies won’t fit a stock tank.
• Buying jets you don’t need for what’s really a soaking tub.
• Forgetting the pipe, cement and hole saws, which aren’t in the kit.
• Putting a water feature on the jet pump.
• No insulation on a metal tank, which means slow heating and high bills.
• Doing the electrics yourself. Get a qualified electrician.
• Cheap no-name parts that save a few pounds and cost you a season.

Ready to build?

If you’re building a stock tank or wooden tub, pick the stock tank or cedar/wood kit that matches the features you want. If you’re building in-ground, start with my DIY hot tub plans and their full parts list.

FAQs

Is there a complete kit for an in-ground hot tub?

Not as a single box. In-ground tubs are all different sizes and need gunite jet bodies set into the walls, so you start with plans or a custom design that includes a full parts list or quotation.

What comes in a stock tank hot tub kit?

My kits include a Balboa spa pack with a heater and topside control, a pump, a 25 sq ft cartridge filter, two lower drains, fittings and valves, a guide, and (on the jetted versions) jets and a blower. You add the tank, PVC pipe and cement.

How much does a DIY hot tub kit cost?

My stock tank and cedar/wood kits range from $1,399 for heating and filtration only to $1,799 for 16 jets, plus the tank or tub, pipe and electrics.

Do I need an electrician?

Yes. A spa pack needs a dedicated, RCD- or GFCI-protected circuit. In England and Wales it’s notifiable under Part P, and in the USA it usually needs a permit and inspection.

Can I use a stock tank kit on a wooden hot tub?

There’s a dedicated cedar/wood version of each kit, with a guide written for wooden tubs, so I’d use that.

Can I add jets later?

It’s much easier to choose the jetted kit up front. Adding jets later means cutting new holes and replumbing, and the heating and filtration kit’s small pump isn’t sized for jets.

Building your own tub? Tell me what you’re planning in the comments below. I read them all.

Cheers,
Andi

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Thanks - Andi

 

Hi, Andi here. I own Buildahottub.com 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.

Fast forward to 2025, I've helped over 1400+ 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