Why choose an outdoor sauna?
An outdoor sauna gives you the hot, high-temperature Finnish experience that an indoor infrared cabin cannot, and it keeps the heat, humidity and any wood smoke out of the house. Built for the garden and weatherproofed for the British climate, it reaches a traditional 70 to 90°C, well above the gentler 45 to 60°C of an infrared sauna, and turns the bottom of the garden into a proper recovery space.
The trade-off is that an outdoor sauna is a bigger commitment than a plug-in indoor unit. It needs somewhere sensible to sit, a level and drained base, and either a dedicated electrical supply or a wood-burning flue. Get those right and it is the most authentic sauna you can own at home.
Barrel, cabin or pod: the three form factors
Most outdoor saunas come in one of three shapes, and the shape matters as much as the badge.
A barrel sauna is cylindrical, usually cedar or thermowood, and it is the value entry point. The round profile encloses less cold air, so it heats fast, and the curved roof sheds rain and snow with almost no groundwork. Headroom is tightest at the curved edges. Read the full barrel sauna guide if this is your front-runner.
A cabin sauna is the rectangular, traditional shape: vertical walls, a higher ceiling and often two-tier benching, so there is room to lie flat and to seat four to six people. It is the usual choice for families and the more classic look, but it costs more and needs a proper level base.
A pod or cube sauna is the contemporary, design-led option, a rounded pod or a square cube, often built in 40mm thermally modified spruce. It sits between the two on footprint and aesthetics, and suits a modern garden.
Traditional, electric or infrared heat
There are only two things generating the heat in an authentic outdoor sauna, and the choice is often misunderstood. A traditional sauna and an electric sauna both give you the same hot, humid, high-temperature bathe, with water thrown on the rocks for a burst of steam (loyly); the only difference is whether the rocks are heated by a wood-burning stove or an electric heater. Infrared is the genuinely different one: it warms your body directly rather than heating the air, runs cooler, and is a separate category covered on its own page.
Electric or wood-burning heater?
For a traditional or cabin sauna, the real decision is electric or wood-burning.
Electric heaters are the convenient choice: a thermostat, a timer, quick clean heat and nothing to tend. Most 2 to 6 person cabins use a 6 to 9kW heater, which generally runs on a single-phase domestic supply on its own dedicated circuit; only larger cabins need three-phase power. Heat-up is typically 30 to 45 minutes, weather depending, with barrels at the faster end.
A wood-burning stove gives the crackle, smell and off-grid independence of a proper Finnish sauna, with no heavy electrical install. In return you take on a flue and chimney, a supply of dry logs, manual lighting and tending, more cleaning and a longer heat-up, and in a smoke control area you may need a DEFRA-exempt appliance. Choose electric for control, wood-burning for the ritual.
Materials and weatherproofing for the UK climate
Because it lives outdoors through British winters, the timber matters. Thermowood, which is spruce heat-treated at around 200°C, is the sensible default: the treatment makes it dimensionally stable and far more resistant to moisture and rot, and it needs little upkeep. Western red cedar is the premium choice, aromatic and naturally durable, but dearer and happier out of very exposed or coastal spots. Plain Nordic spruce is the cheapest way in, but it warps and rots sooner if it is not looked after.
Beyond the wood, look for a properly pitched or curved roof with felt or shingles, thicker walls or staves, and insulation if you want to use it efficiently through winter. Done well, a good outdoor sauna works happily in a UK winter, and many owners say the cold-to-hot contrast is when it is best. Where the sauna sits, the base it needs and whether you need planning permission are covered in full on our garden sauna page.
What an outdoor sauna costs to buy and run
As a guide, a compact barrel starts around £3,000, family-size cabins and pods sit from about £5,000, and larger or premium modular cabins run well into five figures, before delivery and installation. Flat-pack kits typically fall between £3,000 and £8,000 depending on size and wood, with installation of about £200 to £1,000 and electrical wiring of £500 to £1,500 on top.
Running cost depends on the heater. For an electric model it is heater power multiplied by time and your unit rate: a 6kW heater over a roughly one-hour heat-up-and-bathe cycle uses in the region of 5.5 to 6 kWh, so about £1.45 to £1.60 a session at the current price-cap rate, with larger 8 to 9kW heaters costing more. A wood-burning sauna costs only logs, often around £5 to £8 a session. Real cost varies with heater size, insulation, the weather and how long you stay in.
Guide prices, correct as of July 2026, with running costs based on 26.32p per kWh (Ofgem cap, 1 October to 31 December 2026). The energy price cap changes quarterly and excludes the daily standing charge and regional variation, so check current rates before budgeting. Guide prices are typical UK costs, not live prices.