The best glass-front indoor saunas

The Traditional 160 is the glass-front cabin we'd buy. The whole front and the door are 8mm grey safety glass, tinted rather than clear, the inside is resin-free thermo-aspen, and LED lighting under the benches lights it from below.

£4,899 includes a 6kW Harvia The Wall with Harvia's Fenix Wi-Fi panel. That's more heater than a solid-walled 4m³ room would get, and it's what you want behind a wall of glass. The limits are a 40A supply and a ceiling of about 2.5m, because Hekla wants 50cm above the 2m cabin for the roof panel and wiring. Outdoor Living builds it in the room for £399 or delivers it flat-packed for £149, and Hekla's warranty is 2 years.

Harvia makes the Variant View in Muurame, Finland, in four straight sizes with large glass walls on the front, spruce inside and out, and aspen benches that can go on either side. Pool and Spa Centre sells each one with a Harvia The Wall heater: £4,540.87 for the 1,210mm by 1,183mm Mini with 3.6kW, up to £7,383.05 for the 2,060mm by 2,033mm Large with 8kW.

The heater pairings show what the glass costs. Harvia's solid-walled Variant at 1,505mm square comes with a 4.5kW heater; the Variant View Small at 1,635mm by 1,607mm gets 6kW. Colour lighting is an optional extra. Most sizes were on back order on 21 October; only the Large showed stock.

Finnmark's Indoor Cube sets an 8mm tempered glass door and front walls into 40mm thermally modified spruce, a darker timber that suits a modern room. Inside are two tiers of thermo-aspen bench, 121cm long.

It's £4,993.99 as a cabin or £5,522.99 with a 6kW Narvi NM. That heater wants a 32A circuit, and the cabin wants a 230cm ceiling, 150mm clear on every side and a floor that can take 450kg. The glass is on the front only, with solid thermowood on the sides and back. A roof kit comes in the box, so it can move outdoors later if the room changes use.

The Fenix is black-treated spruce outside with a front of two fixed 8mm glass panels and an 8mm glass door, about 3.6m² of glass on the 1620 size by the dimensions in Harvia's parts list. Behind the timber the walls are about 75mm thick, with glass fibre insulation and an aluminium foil vapour barrier, the only glass cabin here whose seller spells out the insulation.

£8,737.18 includes a Harvia Virta heater with the Xenio controller, stones and accessories, and the upper bench is 1,865mm by 600mm, long enough to lie on. Pool and Spa Centre doesn't give the heater's output, both sizes were on back order, and Harvia asks for a 230cm ceiling.

This CenturaHeat cabin has a full-height glazed front and a glazed side wall screened with timber slats, so it reads as glass from two directions. It's 1,500mm by 1,200mm and 1,900mm tall, with a full-width rear bench and a 3kW Harvia BC30E heater on a 16A supply, for £3,608, down from £4,244.74.

3kW behind two glazed walls is modest, and the listing gives no wall thickness, so expect a slower warm-up than the 6kW cabins above. Pro-Line notes that the 2-person figure comes from the bench layout rather than a stated rating. The 16A supply is the upside: it's the smallest stated supply on this page and the simplest circuit to add.

£3,306 buys a 1,500mm by 1,200mm hemlock cabin with a tempered glass front, a 4.5kW Harvia stove, a digital panel with app control and seats for 3 to 4. It runs on a 20A hard-wired supply and is warranted for 2 years on the timber and 1 year on the electrics.

The price also includes FM radio, Bluetooth speakers, coloured star lights and an oxygen ionizer, which add things to go wrong without adding heat. Four adults in 1.5m by 1.2m is tight, so plan on two or three. The 4.5kW heater costs about £1.18 an hour at full power.