Mande Spa MW20 Outdoor Sauna

Description

The Mande Spa USA MW20 ThermoWood Outdoor Sauna is the crown jewel of the MW Series -- the largest, most spacious sauna in the Mande Spa collection and a genuine outdoor retreat built for five to six people. If the MW12 is designed for couples and the MW16 for families, the MW20 is built for those who want the full experience: room to truly spread out, gather with friends, host wellness sessions, or simply sink into a level of comfort that smaller saunas cannot match.

 

At nearly 6.5 feet wide and 6.6 feet deep, the MW20 delivers a full-scale sauna interior with 68.9 inches of interior length and 64 inches of uninterrupted bench width. The upper bench runs 23.6 inches deep -- wide enough for a full reclined position -- and the lower bench adds another level of seating for a complete multi-person layout. This is a sauna you live in, not just sit in.

 

Like every model in the MW Series, the MW20 is handcrafted in Lithuania by skilled artisans who bring generations of European sauna tradition to every joint, panel, and detail. The structure is built entirely from Scandinavian ThermoWood -- sustainably sourced timber that has been thermally modified at extreme temperatures through a completely chemical-free process. The result is a wood that is naturally resistant to rot, warping, cracking, and decay across all seasons and climates, without any preservatives or chemical treatments. It is safer for your family and better for the environment than conventionally treated lumber.

 

Inside, LED under-bench lighting creates a warm, spa-like ambiance, while the integrated ventilation system maintains consistent airflow and heat distribution. Tempered glass panels on the full-width door and side windows bring in natural light and create a sense of openness that transforms the experience. A bituminous shingle roof seals the structure against rain, snow, and UV exposure year after year.

 

The MW20 ships as a flat-pack kit in a secure OSB crate on a skid and assembles with standard tools using the detailed build guide included with every unit. No cranes, no specialized contractors, no guesswork.

 

Mande Spa USA is the American branch of Mande Wood (UAB Seilas), a leading European wellness manufacturer headquartered in Lithuania, with a distribution network across the United States and throughout Europe at mandespa.eu. Every sauna reflects generations of Lithuanian sauna culture combined with modern precision engineering.

 

Backyard Prime Living is an authorized reseller of Mande Spa USA. Every purchase includes full manufacturer warranty support and our commitment to extraordinary customer care.

 

NOTE: All saunas ship via LTL freight carrier as curbside delivery. A heater is not included in the base unit. Heater options are available as an add-on at time of order. A certified electrician must complete all heater installations.

 

Features

• Handcrafted in Lithuania by Expert Sauna Artisans -- Built by skilled craftsmen who combine generations of European sauna tradition with modern engineering precision. Every joint, panel, and detail reflects that care.
• Sustainably Sourced Scandinavian ThermoWood Construction -- Thermally modified through a chemical-free heat-treatment process that makes the wood naturally resistant to rot, warping, cracking, and decay. No chemical preservatives. Safe for families and eco-responsible by design.
• Maximum Capacity for 5 to 6 People -- At 83.1 in wide by 78.7 in deep, the MW20 is the largest model in the MW Series and the only one purpose-built for groups of five or six. Interior length of 68.9 in and bench width of 64 in deliver a genuinely spacious, full-scale sauna experience.
• Full-Width Tempered Glass Front -- The MW20 features an expansive tempered glass door and window configuration that spans nearly the full front face of the sauna, flooding the interior with natural light and creating an open, resort-style aesthetic unlike any other model in the collection.
• Rounded Cube Modern Design -- Softly rounded corners, a flat roof, and a contemporary silhouette that integrates naturally with modern homes and large outdoor living spaces.
• Tempered Glass Door and Windows -- Multi-pane tempered glass on the door (25.6 in wide x 69.7 in tall) and panoramic side windows maintains heat retention while providing natural light and privacy.
• LED Under-Bench Lighting -- Warm LED strips beneath the ThermoWood benches create a calming, spa-like ambiance for any time of day or evening session.
• Two-Level ThermoWood Sunbed Benches -- A deep upper bench (23.6 in deep) and lower bench (19.7 in deep), both spanning 64 in wide, accommodate up to 6 users in seated, reclined, or full sunbed positions simultaneously.
• Integrated Ventilation System -- Promotes steady airflow across the larger MW20 interior to maintain consistent heat distribution and optimal sauna conditions.
• Bituminous Shingle Roof -- Weather-resistant roof tiles protect against rain, snow, moisture infiltration, and UV degradation through all four seasons.
• 1.7 in ThermoWood Wall Construction -- Substantial wall panels deliver excellent thermal retention across the MW20's full interior volume.
• Precision Joinery Construction -- Traditional woodworking techniques deliver tight, stable joints that hold up under repeated thermal expansion and contraction cycles.
• Flat-Pack Kit Delivery -- Ships in a secure OSB crate on a skid. Assembles with standard tools using the included build guide. No heavy equipment needed.
• Step-by-Step Build Guide Included -- Specific to the MW20, making self-assembly achievable for most homeowners.
• Year-Round Outdoor Use -- ThermoWood and bituminous roofing engineered for all-climate performance, from frozen winters to humid summers.
• Low Maintenance -- Long-lasting ThermoWood means more time relaxing and less time on upkeep.
• Heater Options Available at Time of Order:
  • Harvia Kip 8.0kW with built-in controller
  • Harvia M3 Wood-Burning Heater with full chimney set
  • No Heater (structure only)
• Expected Heat Up Times: 
  • MW20 (8kw electric) - Approximately 35-45 minutes

  • MW20 (M3 wood-burning): Heat-up time varies depending on fire management and wood type.

• 5-Year Warranty on Structure -- Backed by Mande Spa USA manufacturer warranty.
  

 

What's Included

INCLUDED IN THE CRATE:

• MW20 ThermoWood Outdoor Sauna Kit (all structural panels, walls, floor, roof)
• Tempered glass door assembly (25.6 in wide x 69.7 in tall opening)
• Tempered glass side and front window panels
• LED under-bench lighting
• ThermoWood upper and lower interior benches (sunbed style)
• Bituminous shingle roof system
• Integrated ventilation components
• Stainless steel fasteners, hinges, and hardware
• MW20 Build Guide (step-by-step assembly instructions)
• MW20 Floor Plan (engineering dimension drawings)
• If heater option selected at order: Harvia electric or wood-burning heater unit

 

NOT INCLUDED / SOLD SEPARATELY:

• Sauna heater (unless selected as add-on at time of order)
• Heater stones (if applicable to selected heater model)
• Electrical wiring and dedicated 240V circuit (must be installed by a certified electrician)
• Foundation or base platform (concrete pad, deck frame, or compacted gravel base recommended -- not supplied)
• Cold plunge tub or hot tub (available separately from Mande Spa USA)
• Exterior weather or protective cover
• Aromatherapy accessories (ladle, bucket, essential oils)
• Thermometer or hygrometer

 

DELIVERY NOTE: Ships via LTL (less-than-truckload) freight carrier. Curbside delivery only with liftgate service. White glove delivery and in-home placement are not offered. Delivered by appointment, Monday through Friday during standard business hours. Unit ships unassembled in a secure OSB flat-pack crate mounted on a skid. Inspect the crate before signing the delivery receipt. All shipping damage claims must be reported within 5 days of delivery -- note any visible damage as "subject to inspection" on the delivery receipt at the time of delivery.

 

Specifications 

Manufacturer: Mande Spa USA (American branch of Mande Wood / UAB Seilas)
Model: MW20 ThermoWood Outdoor Sauna
Country of Origin: Lithuania
Sauna Style: Rounded cube outdoor sauna (flat-pack kit)
Collection: MW Series (MW12 / MW16 / MW20)

OCCUPANCY: Capacity: 5 to 6 people

EXTERIOR DIMENSIONS:
Overall Width: 83.1 in  (6 ft 11.1 in)
Overall Depth: 78.7 in  (6 ft 6.7 in)
Overall Height: 83.5 in  (6 ft 11.5 in)

INTERIOR DIMENSIONS:
Interior Width: 75.6 in  (6 ft 3.6 in)
Interior Depth: 68.9 in  (5 ft 8.9 in)
Interior Height: 83.5 in  (6 ft 11.5 in)
Interior Width wall to wall: 78.0 in

DOOR OPENING:
Door Width: 25.6 in
Door Height: 69.7 in

BENCH DIMENSIONS:
Bench Width (both): 64 in across interior
Upper Bench Depth: 23.6 in
Lower Bench Depth: 19.7 in
Upper Bench Height from floor: 78.7 in
Lower Bench Height from floor: 45.7 in
Lower Bench alternate height reference: 28.0 in (from floor to lower bench support base)
Bench support gap: 1.6 in off floor
Base/leg height: 3.5 in

ADDITIONAL INTERIOR MEASUREMENTS:
Distance bench face to glass wall: 15.7 in
Gap between benches: 2 in
Bench support depth: 10 in
Side / heater section: 19.7 in wide x 34.3 in high x 16.5 in deep
Total interior depth with benches: 68.9 in
Panel clearance: 1.7 in (wall thickness, consistent all sides)

WALL AND STRUCTURE:
Wall Thickness: 1.7 in (ThermoWood panel construction)
Floor/base thickness: 3.5 in (including leg/base height)

WEIGHT:
Assembled Weight: 1,565 lbs

MATERIALS:
Exterior and Structure: Scandinavian ThermoWood (thermally modified, chemical-free)
Interior Benches: ThermoWood sunbed style (two-level: upper and lower)
Door and Windows: Tempered glass
Roof: Bituminous shingle tiles
Fasteners: Stainless steel hardware throughout
Lighting: LED under-bench lighting
Ventilation: Integrated passive ventilation system

HEATER RECOMMENDATION (add-on at time of order):
Electric: Harvia Kip 8.0kW with built-in controller
No Heater: Structure only

• Harvia KIP 8.0kW
  • Voltage: 240V
  • Phase: Single phase
  • Recommended Breaker: 40–50 Amp (verify per manual)
  • Wiring: Copper only
  • Sauna Room Size: Medium rooms

• Harvia M3
  • Wood Burning Heater
  • Steel Construction
  • Designed for traditional Finnish sauna operation
  • Requires chimney system
  • Requires floor protection
  • Requires wall shielding

 

HEATER OPTIONS (add-on at time of order):
Electric: Harvia Kip 8.0kW with built-in controller
Wood-Burning: Harvia M3 with full chimney set
No Heater: Structure only

ELECTRICAL REQUIREMENTS (if electric heater selected):
Voltage: 240V AC
Amperage: 30 Amp dedicated circuit (verify with selected heater model and local electrician)
Note: A certified electrician must install all heater wiring. Do not connect to a shared household outlet.

SHIPPING:
Ships Via: LTL freight carrier
Delivery Type: Curbside with liftgate -- by appointment Mon through Fri
Packaging: OSB flat-pack crate on a skid
Lead Time: 2-4 weeks

DURABILITY:
Weather Resistance: High resistance to moisture and decay
Climate Suitability: Year-round outdoor use in all climates

WARRANTY:
Structure: 5 years (Mande Spa USA limited manufacturer warranty)
Heaters / Accessories: All heater and accessory sales are final and non-refundable. Harvia heater warranty applies separately.
Warranty Exclusions: Improper installation or handling, unauthorized modifications, misuse, negligence, or intentional damage