Garden sauna vs indoor infrared sauna: costs, space and power
An indoor infrared cabin and a traditional garden sauna are very different purchases. One plugs into a wall socket in a spare room. The other usually needs a hard-wired electrical circuit, a prepared base and a decision about planning rules. This guide compares them on the things that decide the purchase: price, space, electrics and running costs.
We use published specifications from UK retailers, checked on 12 November 2026, and show the arithmetic for running costs. We have not tested any saunas and make no health claims; the guide is about the practical side of buying.
The short answer
Choose an indoor infrared cabin if you have a suitable room, a ceiling of around 2.2 to 2.5 metres and want a simple plug-in install. Choose a garden sauna if you have outdoor space, are happy to pay an electrician for a dedicated circuit and want a traditional hot sauna. Running costs are low for both: roughly 30p to 60p an hour for the infrared examples below, and about 60p to £2 a session for a small traditional electric heater.
Side-by-side
| Indoor infrared (2 person examples) | Garden sauna (2 person electric examples) | |
|---|---|---|
| Power | 1,200 W to 2,400 W | 4.5 kW heater for a 2 person barrel; 6 kW for larger |
| Connection | Standard 13 amp socket, no extension lead | Hard-wired through an isolator, not a three-pin plug |
| Footprint | About 1.3 m x 1.15 m to 1.37 m x 1.37 m | Barrel from about 1.5 m x 1.9 m (2 person) |
| Height | About 2.0 m, plus ceiling clearance | About 2.04 m (barrel) |
| Weight | Flat-pack cabin (not stated on the pages we reviewed) | About 450 kg for a 2 person barrel |
| Base | Level, washable floor | Gravel, slabs, concrete pad or sound decking |
| Published prices | £2,640 to £4,977.50 (Oceanic); £3,599 (Hekla) | From £1,999.99 (a barrel range at Costco) |
These are examples of what is on sale, not a recommendation of any model. Several pages were showing options, delivery charges or sold-out items; check the current price and availability.
Space
Indoor infrared
Two published examples show what to measure. The Hekla Infrared 130 is 130 x 115 x 200 cm and the supplier asks for a ceiling of about 250 cm. The Oceanic IR2020 is 136.8 x 136.8 x 202 cm; it needs a level, washable floor, a 25 mm air gap around the cabin and a minimum ceiling height of 2,200 mm. Both arrive flat-packed. Hekla says assembly takes two or three people, and offers delivery and installation for £249 (kerbside delivery only is £99). Oceanic says a two-person cabin typically takes around one day to install.
Measure the door and stairs as well as the room. A flat pack still needs to get inside.
Garden sauna
Finnmark lists barrel saunas from a micro size (150 x 190 cm diameter x 204 cm high, 2 persons) up to large 6 to 8 person models at 300 x 225 cm. Costco's range lists a 2 person barrel at 450 kg, a 2 to 4 person at 500 kg and a 4 to 6 person at 575 kg. Delivery is boundary only onto level hard standing, and the crate can weigh up to 400 kg, so you must plan how to move it from the road to the garden.
Electrics and power
Indoor infrared: usually a plug
Both infrared examples run from a standard 13 amp socket with no extension lead; Hekla advises against sharing the socket with other appliances. A 13 amp plug at 230 V can deliver at most about 2.99 kW, so the Hekla's 2.4 kW is close to the limit while the Oceanic's 1.2 kW (four 300 W heaters) has plenty of headroom. Oceanic also states that the electrical connection to the heater must be made by a qualified electrician.
Garden sauna: a dedicated circuit
Electric garden sauna heaters are normally hard-wired. A 4.5 kW heater from Oceanic needs an isolated 230 V single-phase or 400 V three-phase supply installed by a qualified electrician, is hard-wired through an isolator switch, and cannot run from a three-pin plug. Finnmark says most domestic models need a 32 A or 40 A supply (smaller heaters can operate on 16 A) and a dedicated circuit, typically on a 32 or 40 A MCB.
The electrician must also confirm your existing installation can take the extra load. The IET's guidance on hot tub supplies, which applies the same principles of protected, properly buried cable, advises cable buried at least 500 mm deep with marker tape. Ask for an Electrical Installation Certificate; new circuits in England are notifiable under Part P.
Running costs: the maths
Electricity is priced at the Ofgem cap of 26.32p per kWh for 1 October to 31 December 2026. Update the figure for your own tariff.
Infrared
Oceanic IR2020: 1.2 kW x 1 hour = 1.2 kWh x 26.32p = 31.6p an hour.
Hekla 130: 2.4 kW x 1 hour = 2.4 kWh x 26.32p = 63.2p an hour if every panel runs at full power for the whole hour. Hekla's own page estimates up to 57p a session, or about £7 a month at three sessions a week.
Traditional electric
Finnmark says modern electric heaters typically bring a domestic sauna to 70 to 80°C in 30 to 45 minutes. For a 4.5 kW heater at full power:
- 30 minutes: 2.25 kWh = 59p
- 45 minutes: 3.38 kWh = 89p
- 45 minute heat-up plus a 30 minute session, with the heater at full power throughout (an upper bound): 5.63 kWh = £1.48
For a 6 kW heater the same cases are 79p, £1.18 and £1.97. Real sessions cost less than the upper bound, because the thermostat cycles the heater once the cabin is at temperature.
Per week
Three sessions a week: infrared at 1.2 kW is about 95p; a 4.5 kW traditional sauna is about £1.78 to £4.44.
The standing charge is paid either way and is not included.
Planning and building rules
For a garden sauna, the Planning Portal's outbuilding rules in England are the starting point. Outbuildings must be single storey with eaves up to 2.5 m and an overall height up to 4 m with a dual-pitched roof (3 m for other roofs); within 2 m of a boundary the building can be no taller than 2.5 m; a platform cannot be higher than 0.3 m; and buildings may not cover more than half the land around the original house. They cannot sit forward of the principal elevation, and any outbuilding in the curtilage of a listed building needs planning permission. In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites, outbuildings more than 20 m from the house are limited to 10 m² in total. Finnmark adds that flats, maisonettes and properties with restrictive covenants need extra checks. Local rules, including Article 4 Directions, can restrict these rights.
A barrel at around 2 metres high sits within these height limits, but check the specifics for your property with the local planning authority. An indoor cabin is not an outbuilding, so these rules do not apply to it, but check any lease or insurance terms.
Base for a garden sauna
Finnmark says no concrete foundations are needed, but the base must be stable and level. Its options are compacted gravel or crushed stone 100 to 150 mm deep, levelled paving slabs covering the full footprint, a poured concrete pad, or sound decking, and it says never to put a sauna on grass or unprepared ground. With a 450 kg or heavier barrel, ask a specialist to check any deck.
How to decide
- No outside space, or want to avoid an electrician's circuit: indoor infrared.
- Want a traditional sauna: garden barrel or cabin, budget for the circuit and base.
- Check the ceiling height of any indoor room before you shortlist.
- Check your consumer unit has room for a new circuit before you shortlist a garden sauna.
- Check how the delivery will reach the final position.
Frequently asked questions
Do I need planning permission for a garden sauna?
Often not, if it meets the Planning Portal's outbuilding conditions, but listed buildings, protected areas, front gardens, flats and certain heights need checks. Ask your local planning authority if in doubt.
Can an infrared sauna run from a normal socket?
The two examples we checked do, on a 13 amp socket with no extension lead.
How much does a sauna cost to run?
From the examples above, about 32p to 63p an hour for infrared, and roughly 59p to £1.48 per session for a 4.5 kW traditional heater, at 26.32p per kWh.
Is a garden sauna worth it in winter?
You still need to reach it, and the heat-up time is 30 to 45 minutes for electric heaters, so it is a practical, not a price, question. Think about lighting, a path and somewhere to change.
Related guides: cold plunge tub buying guide.
Sources (checked 12 November 2026)
- Outdoor Living Hot Tubs, Hekla Infrared 130 (size, 2.4 kW, 13 amp, £3,599, installation prices): outdoorlivinghottubs.co.uk
- Oceanic Saunas, IR2020 infrared sauna (size, 1,200 W, 13 amp, ceiling, price): oceanic-saunas.co.uk
- Oceanic Saunas, 4.5 kW sauna heater (hard-wired, 4 to 6 cubic metres): oceanic-saunas.co.uk
- Costco, Vidalux outdoor barrel sauna range (weights, heaters, delivery, starting price): costco.co.uk
- Finnmark Sauna, electric or wood-burning heaters guide (heat-up time, supply): finnmarksauna.com
- Finnmark Sauna, guide to barrel saunas (sizes, base, planning notes): finnmarksauna.com
- Planning Portal, outbuildings: planningportal.co.uk
- IET, domestic electrical supplies to hot tubs (cable burial, Part P): electrical.theiet.org
- EDF, energy price cap 1 October to 31 December 2026 (26.32p/kWh): edfenergy.com