Mande MW20 ThermoWood Outdoor Sauna – 5-6 Person

The Mande MW20 is a 6 person outdoor sauna for five to six people, built from Scandinavian ThermoWood® and handcrafted in Lithuania. It is the largest model of the MW series and the only one that also takes a wood-burning stove.

Mande MW20 at a glance

The MW20 seats five to six people on a footprint of 78.7" × 77.6", with a tempered glass front and ThermoWood® benches lit from below.

Electric or wood-burning?

Both work in the MW20. The Harvia KIP 8.0 kW needs a dedicated 240 V circuit (typically a 40-50 A breaker, check the heater manual) and heats with a controller, including an optional WiFi controller for app control. The Harvia M3 needs no power but a chimney, a non-combustible floor protection and wall clearances installed to code; it is for outdoor use only.

What is ThermoWood?

ThermoWood® is Scandinavian softwood that has been heat-treated without chemicals. The treatment lowers moisture absorption and improves dimensional stability and resistance to rot and insects. Left untreated, the exterior turns silver-grey over time; exterior oil every 2-3 years keeps the warm tone.

Features

• Tempered glass door and windows
• ThermoWood® benches with LED lighting underneath
• Built-in ventilation
• Bituminous roof tiles and exterior metal roof straps for rain and snow
• Doors, benches and back walls arrive pre-assembled

Site prep and assembly

You need a level, solid base: a concrete slab, a reinforced deck, a compacted paver base or compacted gravel with perimeter framing. Two people assemble the MW20 in about 12 hours; no special carpentry tools are needed.

Delivery

The MW20 ships flat-packed in a wooden crate by freight, curbside with a liftgate, free in the lower 48. You move it to the base. A Harvia heater ordered with the sauna ships separately, directly from Harvia.

Questions about the MW20

Can the MW20 go indoors?

Only with the electric heater, without the roof tiles, roof straps and rear siding, following local building and fire codes. Wood-burning stoves are not permitted indoors or in garages.

Is it insulated?

No separate insulation is used; the walls are solid ThermoWood® profiles built for traditional high-heat sauna use.

See all 6 person outdoor saunas, compare wood-burning saunas or read the backyard sauna guide.