How to build your own hot tub for less than €100

There’s nothing more relaxing than ending the day with an open-air soak under the stars

From hikers and triathletes to gardeners and exhausted parents, a hot bath at home under the stars is something everyone dreams about. Unfortunately, only the elite few can afford the expensive outdoor tubs on the market, some which run into tens of thousands of euros and cost thousands more in upkeeping.

But follow the guidelines below and just about anyone with a large garden or open space and some DIY determination can have just that – all for less than €100.

On a recent visit home to Ireland from my base in Istanbul, I cleaned out a fire-powered hot tub I had put together 10 years previously in my family's garden in Tipperary. The original idea came to me when seeing something similar depicted in the acclaimed 2004 Afghan film, Osama, and I thought as I lay in the roasting water, safe from the freezing April night's wind, this is something pretty much anyone could enjoy.

To make the tub I salvaged an old cast iron bath lying idle but which can be bought on eBay or for as little as €50. Using the tub, about three dozen concrete blocks, several metal sheets to act as steps and a bench top, the construction is straightforward once you’ve the means of lifting the tub into place, totalling about a day’s work. A bath with a flat edge all around its perimeter, as I use, works best for helping to evenly distribute the weight of water and bather.


First, set in cement four sets of six-inch blocks on their side, making sure your measurements allow for the tub’s edges at each corner to catch the inward side of each set of blocks. Once the tub is lifted on to the blocks about 3ft high and, crucially, made level, fill it with water and light a slow-burning fire for three hours that just about licks the underneath of the tub, so as to not crack the tub’s enamelled interior.

As I found out to my misfortune early on, plastic bath plugs don’t hold up well to the fire’s intense heat, so use a metal or chrome equivalent (they come in standard size). The fire need not flame the length of the bath, and though it will take longer for the water to heat, it’s best to keep the tip of the fire away from the plug end, just in case.

Extremely careful

It goes without saying that when dealing with fire be extremely careful: Before even thinking of getting into the tub, fill it with water and place at least 50kg worth of weights inside. Light and feed a fire for three hours, and repeat this several times over the course of several days to be sure it can bear your weight and the heat from the fire.

If you’re not terribly steady on your feet, erect a 10ft pole set in cement to guide you up and down the steps or, if an elevated tub such as the one pictured is too tricky to climb into, simply sit the tub on a single layer of blocks and dig a 2ft-deep pit into the ground for the fire. Spread pea stone along the fire pit so as not to scorch the earth.

Before it comes time to enjoy the fruits of your labour, keep a large bucket of cold water at hand in case the tub becomes too hot, which in my experience, invariably happens. Then lie back and take in the view of aircraft, passing satellites and shooting stars.


One disused, functioning cast iron bath tub
24 six-inch concrete blocks
Nine four-inch blocks on edge, or a step-stairs
Four metal panels, totalling 70cm square and 1cm thick
10kg pea stones