The best 2-person indoor saunas

Oceanic's 1520 is the 2-person cabin we'd buy: 1,368mm long, 1,060mm deep and 2,020mm tall, made in Wolverhampton from 50mm insulated panels, with a 3kW heater, built-in digital controls, a bench kit and accessories for £2,141. It's the cheapest complete 2-person cabin we found, and only the Harvia Variant S and CenturaHeat's 2.3kW cabin take less floor.

The 1520's bench is for sitting. Oceanic makes the same cabin longer: the 1525 is 1,675mm for £2,350 and the 1530 is 1,983mm for £2,651, the one to pick if either of you wants to lie down. All three use 3kW, which suits a room this size and costs about 79p an hour at full power. Oceanic builds to order in 6 to 7 weeks, and its 5-year warranty covers the timber.

Hekla's 160 is 161cm wide and 120cm deep, with 150cm inside wall to wall, enough for two to sit with space between them or three at a squeeze. The whole front is 8mm grey safety glass, the interior is thermo-aspen, and £4,899 includes a 6kW Harvia The Wall heater with a Wi-Fi panel.

6kW is a lot of heater for a 4m³ room: Oceanic rates its 4.5kW for rooms of 4 to 6m³. The extra covers the heat lost through the glass and warms the cabin faster, but it costs about £1.58 an hour at full power and Hekla specifies a 40A supply.

The other limit is height. Hekla wants 50cm above the 2m cabin, so the room needs a ceiling of about 2.5m.

Finnmark's cube puts 40mm thermally modified spruce, an 8mm glass door and front, and two tiers of thermo-aspen bench on a footprint of 145cm by 133cm. The bench is 121cm long, which seats two side by side but won't let anyone lie down.

It's £4,993.99 without a heater or £5,522.99 with a 6kW Narvi NM, and that heater needs a dedicated 32A circuit. Plan the room around 175cm by 165cm, because Finnmark asks for 150mm clear on every side, and a ceiling of 230cm for a cabin that is 221cm tall. It comes in one box 209cm long, and Finnmark says most buyers build it in a weekend.

CenturaHeat's compact hemlock cabin stands on 1,200mm by 1,100mm and is 1,900mm tall, the lowest here, with two-tier benches, a full-height glazed front and a glazed side panel. A 2.3kW Harvia BC23E with an external controller heats it, and it costs £3,542.15, down from £4,167.24.

2.3kW is the smallest heater on this page and the cheapest to run, at about 61p an hour at full power. The cost is a slower warm-up in a cabin with two glazed sides, and Pro-Line's listing gives neither the panel thickness nor the supply the heater needs, so have your electrician read the heater manual before quoting. It's £1,401 more than Oceanic's 1520, and the difference buys the glazing and a lower roof line.

At 1,150mm square, the Variant S is the narrowest cabin here. Harvia gives its room volume as 3.48m³ and pairs it with a 3.6kW Delta heater, and Pool and Spa Centre's £4,205.33 includes that heater, stones, a glass door, upper and lower abachi benches and an equipment pack.

A square cabin fits an alcove or the end of a dressing room where a longer one won't, but a bench across 1.15m is for sitting, and Harvia doesn't give a seating number. It's also £2,064 more than Oceanic's 1520.

The 1,150mm size was on back order on 21 October. Harvia's manual asks for a room at least 2,150mm high for assembly.