The best wood-burning sauna stoves

5 stoves for saunas without a 32A circuit, from a £464 Harvia that comes with its stones to a £1,450 Legend that holds 120kg of them, scored on the room size they heat, the stone load and what the flue adds to the bill.

Updated 21 October 2026By the SaunaReviews editorial team5 saunas comparedHow we score
A stone-filled wood-burning stove inside a sauna
Our pick: HUUM HIVE Wood 13, £1,010

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The short version

RankSaunaBest forPriceHeater in priceScore
1HUUM HIVE Wood 13Garden cabins of 6 to 13m³£1,010Yes9.1
2Harvia M3A wood fire for under £500£464Yes8.8
3Harvia Legend 150Long sessions, soft steam£1,450Yes8.6
4Narvi NC 20 Water TankBig rooms and hot water£1,166.99Yes8.4
5Narvi Kuru 14Bigger rooms on a budget£629Yes8.2

Our pick

1. HUUM HIVE Wood 13

Wood-burning stove, 13kW

9.1/10

The HIVE Wood 13 is a round steel cage of stones over a firebox with a glass door, rated at 13kW for rooms of 6 to 13m³. It holds 90kg of stones, 3 times the Harvia M3's load, so the steam stays soft and keeps coming after the fire burns down. Finnmark Sauna sells it for £1,010, down from £1,242.

HUUM's manual puts the 115mm outlet on top of the stove and asks for 1.2m clear above it and a non-combustible base at least 60mm thick. Logs can be up to 30cm long, and a full heat-up uses about 8.6kg of wood in loads of up to 4kg. HUUM lists the total efficiency at 67%.

Add about £200 for stones and £727 to £918.99 for one of HUUM's chimney sets, which puts the kit near £2,000 before labour. A heat exchanger can be fitted under the stones to warm washing water.

Buy it if

  • You want the softest steam at this size
  • Your cabin is 6 to 13m³ after allowances
  • You'd like the option of hot water

Skip it if

  • Your budget for stove and flue is under £1,500
  • You want to load it from outside the hot room
  • Your room sizes out above 13m³
Full specification
Output
13kW
Room volume
6 to 13m³
Flue
115mm outlet on top
Stones
90kg, bought separately
Logs
Up to 30cm long
Clearance above
1.2m
Size (H × W × D)
75 × 45 × 46cm
Weight
47kg

Best value

2. Harvia M3

Wood-burning stove, 16.5kW

8.8/10

£464 at SaunaShop buys the M3 with its stones, the cheapest complete way to put a wood fire in a sauna. Harvia rates it at 16.5kW for rooms of 6 to 13m³, and it takes a 115mm flue from the top or the back, which gives you some freedom over where the chimney goes.

The catch is a small stone load. It holds 30kg, so the steam is quick and sharp and drops away once the fire dies, and you keep feeding it through the session. Harvia lists 250mm to combustible walls at the sides, 300mm behind and in front, and 1.2m to the ceiling.

SaunaShop sells a heat shield kit for it from £209, which cuts those distances in a tight cabin. A pipe water heater can be fitted on its flue later if you want hot water.

Buy it if

  • You want a real fire for the least money
  • Your cabin is 6 to 13m³ after allowances
  • You want a choice of top or rear flue

Skip it if

  • You want steam that lasts after the fire
  • You'd rather not feed it during a session
  • Your room sizes out above 13m³
Full specification
Output
16.5kW
Room volume
6 to 13m³
Flue
115mm, top or back
Stones
30kg, included
Clearance
250mm sides, 300mm front and back, 1.2m above
Size (H × W × D)
71 × 39 × 43cm
Weight
45kg

Most stone

3. Harvia Legend 150

Wood-burning stove, 16kW

8.6/10

The Legend 150 wraps 120kg of stones in a black steel frame around the firebox, 4 times the M3's load in a stove rated for the same 6 to 13m³. That mass is the point: the stones carry the room when the fire is low, and the steam stays gentle round after round. Aqualine Saunas sells it for £1,450, down from £1,610.

Harvia lists clearances of 200mm at the sides, 250mm behind and 500mm in front, with 1m to the ceiling, and the outlet is 115mm. It weighs 61.5kg empty and over 180kg once the stones are in, so check the floor or base can take it.

Stones are extra, around £240 for 120kg. More stone also means a longer heat-up, so this is a stove for long weekend sessions rather than a quick half hour after work.

Buy it if

  • You want the softest steam a stove gives
  • Your sessions run for hours
  • Your floor or base can take 180kg

Skip it if

  • You want the sauna hot quickly
  • Your stove budget is under £1,500
  • You'd rather not lift 120kg of stones into place
Full specification
Output
16kW
Room volume
6 to 13m³
Flue
115mm
Stones
120kg, bought separately
Clearance
200mm sides, 500mm front, 1m above
Size (H × W × D)
74 × 53 × 53cm
Weight
61.5kg empty

Hot water option

4. Narvi NC 20 Water Tank

Wood-burning stove, 16kW, 23-litre water tank

8.4/10

The NC 20 Water Tank is Narvi's larger stove with a 23-litre tank on its side, so the same fire heats your washing water. It is rated for rooms of 10 to 20m³, which makes it the stove here for a big cabin or one with bare log walls. Finnmark Sauna sells it for £1,166.99, about £204 more than the NC 20 without the tank.

Narvi's manual gives a 16kW output, 67% efficiency and a 119mm flue outlet, with 150mm clearance at the sides and back, 500mm in front and 1.2m above. The stone load is 50kg, less than the HIVE Wood or Legend, so the steam is livelier and shorter.

Narvi's heat-up schedule for this stove is 3 loads of logs, 9kg in all, each burning for about half an hour. The tank has to be full every time you light it.

Buy it if

  • Your room is 10 to 20m³ after allowances
  • You want hot water without plumbing
  • You'll fill the tank before every fire

Skip it if

  • Your cabin is under 10m³
  • You want the softest steam per kilo of stove
  • You already have hot water at the sauna
Full specification
Output
16kW
Room volume
10 to 20m³
Flue
119mm
Stones
50kg, bought separately
Water tank
23 litres
Clearance
150mm sides, 500mm front, 1.2m above
Size (H × W × D)
74 × 59 × 57cm

Budget Narvi

5. Narvi Kuru 14

Wood-burning stove, 13kW

8.2/10

The Kuru 14 is Narvi's entry stove, £629 at Finnmark Sauna, and it is rated for rooms of 8 to 14m³, a bigger range than the M3 for about £245 more once stones are added. It is a squat 67.5cm tall with a glass door, holds 35kg of stones and takes a 119mm flue.

Narvi's manual gives 13kW and 69% efficiency, against 67% for the HIVE Wood and the NC 20. Heat-up is 3 loads totalling 7.5kg of logs, each burning about half an hour. Clearances are 250mm at the sides and back, 500mm in front and 1.35m above, the tallest requirement on this page.

Stones are extra, about £80, and at 35kg the steam is lively rather than soft. For a larger cabin on a tight budget it is the sensible buy.

Buy it if

  • Your room is 8 to 14m³ after allowances
  • You want a Narvi stove for under £700
  • You don't mind feeding the fire

Skip it if

  • Your ceiling gives less than 1.35m above the stove
  • You want soft steam from a big stone load
  • You want hot water from the stove
Full specification
Output
13kW
Room volume
8 to 14m³
Flue
119mm
Stones
35kg, bought separately
Clearance
250mm sides and back, 500mm front, 1.35m above
Size (H × W × D)
67.5 × 42 × 47.5cm
Weight
49kg

Flue size and clearances for a sauna stove

Sauna stoves have small outlets by wood-burner standards: 115mm on the Harvia and HUUM stoves here and 119mm on the Narvis. The flue has to suit the stove, so buy the maker's own kit or one specified for that outlet, and budget for it properly. HUUM's chimney sets cost £727 to £918.99 at Finnmark Sauna and Narvi's insulated 125mm steel flue kit is £911, as much as a mid-priced stove.

StoveOutletSidesFrontAbove
Harvia M3115mm250mm300mm1.2m
Harvia Legend 150115mm200mm500mm1m
Narvi NC 20 Water Tank119mm150mm500mm1.2m
Narvi Kuru 14119mm250mm500mm1.35m

Distances are to combustible material, which in a sauna means the wall boards and the benches. HUUM shows the HIVE Wood's side and front distances on a diagram in its manual, with 1.2m above, and says a single heat barrier halves them and a double barrier quarters them. Where Building Regulations apply, Approved Document J sets a minimum flue size of 125mm for a wood stove up to 20kW that meets the Clean Air Act, and 150mm for other closed stoves up to 30kW, which is larger than these outlets. Settle the flue design with your installer and building control before you buy it.

A wood-fired garden sauna bought as a package should list the flue in its price. If it doesn't, add £700 to £950 for one.

Building Regulations Part J and HETAS in plain terms

Part J of the Building Regulations covers stoves, flues and hearths. Fitting a stove is notifiable work, which means you either tell building control before the work starts or use an installer registered with a competent person scheme, who self-certifies the job and gets you a certificate within 30 days. HETAS is one of the schemes on the government's list of competent person schemes for solid fuel appliances.

A detached garden sauna is often outside all of this. Schedule 2 of the Building Regulations exempts a detached building of up to 15m² with no sleeping accommodation, and a single-storey one of up to 30m² if it is at least 1m from the boundary or built mainly of non-combustible material. A stove in the house, or in a sauna attached to it, is covered. Exempt does not make the maker's clearances optional, and a registered installer's certificate is useful evidence that the stove went in properly.

Smoke control areas are a separate rule. Many parts of the UK are covered, and gov.uk's smoke control rules name garden buildings such as summerhouses: unless the stove is a Defra-exempt appliance, you can only burn authorised smokeless fuel, and in England the penalty for chimney smoke is up to £300. Ask your council before you buy a wood stove, and remember that planning is a separate question again, decided mostly by the cabin's height and position on the plot.

Firebox size, logs and burn time

Sauna stoves burn in loads. Narvi's manual for the NC stoves says a full firebox burns for about half an hour, and its heat-up schedule uses 3 loads to bring a room at the top of the stove's range to 90°C. After that, 1 or 2 logs, about 1kg, every half hour keeps the heat.

StoveLog sizeWood to heat upMost wood per hour
HUUM HIVE Wood 13Up to 30cm long8.6kg, loads of up to 4kgNot stated
Narvi NC 20 Water TankAbout 33cm long, 5cm thick9kg in 3 loads7kg
Narvi Kuru 14About 33cm long, 5cm thick7.5kg in 3 loads6kg

On Narvi's figures, heating up and then bathing for an hour uses about 11kg of logs. Burn only dry wood: Narvi asks for under 20% moisture, and in England wood sold for home burning in units under 2m³ must be certified at that level under the 2020 domestic solid fuel rules.

Water tank options

A wood stove can heat washing water while it heats the room, which matters in a garden cabin with no plumbing. There are 2 common ways to do it, plus HUUM's heat exchanger, which fits under the stones of the HIVE Wood.

OptionExampleCapacityPrice
Tank built onto the stoveNarvi NC 20 Water Tank23 litres£1,166.99 at Finnmark Sauna, against £963 without
Tank built onto the stoveNarvi Black 20 VS22 litres£1,107 at Finnmark Sauna
Tank around the flue pipeHarvia pipe water heater, for Harvia stoves except the Harvia 5022 litres£375 at Aqualine Saunas

The built-in tank is the neater job, but it adds width and Narvi says it must be filled before every firing. A flue-pipe tank can go on later, which keeps the option open on a stove like the M3. If the cabin can take a circuit after all, an electric sauna heater avoids the flue, the logs and the water question entirely.

Questions buyers ask

Do you need a HETAS installer for a sauna stove?

Not by law, but it is the simplest route. Where Building Regulations apply, a stove must either be notified to building control before work starts or fitted by an installer on a competent person scheme such as HETAS, who self-certifies it. A detached garden sauna under 15m² with no sleeping accommodation is exempt from Building Regulations.

What size flue does a sauna stove need?

The size the stove's outlet and the maker's flue kit are designed for, which is 115mm on Harvia and HUUM stoves and 119mm on Narvi's. Where Part J applies, Approved Document J's minimums start at 125mm for wood stoves, so agree the design with building control first.

How long does a wood-burning sauna take to heat up?

Allow about 1.5 hours for a room at the top of the stove's range. Narvi's heat-up schedules use 3 loads of logs, each burning for about half an hour, to reach 90°C. A smaller room gets there sooner.

Can I use a wood-burning sauna in a smoke control area?

Only with a Defra-exempt stove or authorised smokeless fuel. The gov.uk rules name garden buildings such as summerhouses, and in England smoke from a chimney in a smoke control area can bring a penalty of up to £300. Check with your council and check the stove's exemption before you buy.

How much wood does a sauna stove use?

About 7.5 to 9kg to heat up, then around 1kg every half hour. Those are Narvi's figures for the Kuru 14 and NC 20, and HUUM gives 8.6kg for the HIVE Wood 13. Logs should be under 20% moisture.