Most cold plunge buying guides cover temperature and price. Almost none cover the thing that actually decides whether you keep using it: where you put it. Here's what each location demands.
Indoors: the convenience wins, the plumbing decides
An indoor plunge gets used more, simply because nothing stands between you and it on a cold morning. The constraints are weight, drainage and humidity.
Water is roughly a kilo per litre, so a 400L tub plus occupant is well over half a tonne concentrated in one spot. On a ground floor slab that's a non-issue. On a suspended timber floor or a balcony, get an opinion before you fill it.
Drainage is the daily reality. If emptying means bailing it out by hand, you'll do it once. Site it where a hose can reach a drain, or accept that you'll be running a pump.
Indoors also favours a chilled tub over ice — carrying bags of ice through your house is exactly the friction that ends the habit. A tub that comes with its own chiller removes the trip entirely.
The garage: usually the right answer
A garage solves most of the indoor problems at once. Concrete floor, so weight is irrelevant. Existing drain or an easy run to one. Nobody minds if it splashes. And a power socket for a chiller is usually already there or cheap to add.
The trade-off is temperature swing. An unheated garage in midwinter will do some of the chilling for you, which sounds like a bonus until summer, when an uninsulated space makes the chiller work far harder than the manufacturer assumed. If your garage bakes in August, size the chiller for that, not for January.
Garages also suit rigid tubs better than inflatables, because you're not folding it away — nothing needs to disappear between sessions.
Outdoors: best experience, most commitment
Outdoor plunges are the ones people photograph, and for good reason. They're also the ones that need real thought about the base.
You need a level, load-bearing surface. Decking is often not it — check the joist spacing and span before assuming. A paving slab base is cheap insurance.
Insulation matters far more outdoors, because ambient temperature is working against you constantly. An insulated barrel with a fitted cover holds its temperature between sessions in a way an uncovered tub simply won't, and the cover also keeps leaves, rain and grit out — which is most of the maintenance burden gone.
Think about the walk, too. Three metres of cold wet path in February is a bigger deterrent than people predict. Site it close to a door.
If you're not sure yet, stay portable
Siting decisions are easier once you know how you actually use it — whether that's daily, whether it's mornings, whether you want to be outside. A foldable tub lets you try a location for a month and move it without regret. Plenty of people start in the garage and end up outdoors, or the reverse.
Whatever you choose, get a thermometer you can actually read while you're in it. Location changes how fast the water drifts, and the only way to know what your setup is really doing is to measure it.
The short version
- Garage — best default. Concrete, drainage, power, no aesthetic pressure.
- Indoors — most used, if weight and drainage allow. Chill it rather than ice it.
- Outdoors — best experience, needs a proper base, insulation and a cover.
- Undecided — portable tub, decide in a month.
