The 6-Person Outdoor Scandinavian ThermoWood Cube Sauna Kit is a complete, ready-to-assemble outdoor sauna structure built for residential backyard installation. Constructed from heat-treated ThermoWood, the kit offers strong moisture resistance and dimensional stability suited for year-round outdoor use. The design features tempered glass panels, integrated LED lighting, a high-quality roof, metal banding, and exterior siding. Available in four configurations: kit only (no heater), or bundled with a Harvia KIP 8.0KW electric heater in black or silver, or a Harvia M3 wood-burning heater with stones included.
Why Customers Choose This Product
- Seats up to 6 people — suitable for family or group use
- ThermoWood construction for moisture resistance and outdoor durability
- Tempered glass panels and LED lighting for an elevated interior atmosphere
- Choice of heater configuration: no heater, Harvia electric (black or silver), or Harvia M3 wood-burning
- Exterior stain-ready frame — finish to match your outdoor space
- Suitable for both outdoor and indoor installation
Product Highlights
ThermoWood Construction
The sauna structure is built from heat-treated ThermoWood, which undergoes a thermal modification process that significantly improves moisture resistance and dimensional stability compared to untreated wood. This makes it well-suited for permanent outdoor installation in varying climates.
Tempered Glass Panels
The kit includes tempered glass panels that allow natural light into the sauna interior and contribute to the clean, modern cube aesthetic. Tempered glass is rated for the thermal cycling typical of sauna environments.
Integrated LED Lighting
Built-in LED lighting provides ambient illumination for evening sessions. The lighting is integrated into the kit and does not require separate installation beyond the standard electrical connection.
Heater Options
The kit is available in four configurations. The no-heater option allows you to source and install your own compatible heater. The Harvia KIP 8.0KW electric heater (available in black or silver) includes a built-in controller. The Harvia M3 is a wood-burning heater and includes sauna stones.
Exterior Stain-Ready Frame
The exterior frame is left unfinished and can be stained or sealed in any color to match your outdoor landscape or architectural style.
Outdoor & Indoor Compatible
The kit is designed primarily for outdoor installation with a full roof, metal banding, and exterior siding included. For indoor installation, outdoor-specific components can be omitted — refer to the assembly documentation for indoor configuration guidance.
6-Person Capacity
The interior is sized to comfortably accommodate up to 6 people, making it suitable for household or small group use.
Specifications
| Model | SAK89146 |
| Capacity | Up to 6 persons |
| Construction Material | Heat-treated ThermoWood |
| Glazing | Tempered glass panels |
| Lighting | Integrated LED |
| Roof | Included (outdoor configuration) |
| Exterior Siding | Included |
| Exterior Finish | Unfinished — stain or seal to preference |
| Installation | Outdoor (primary); Indoor (with component modifications) |
| Heater Option 1 | No Heater (kit only) |
| Heater Option 2 | Harvia KIP 8.0KW Electric with Built-In Controller – Black |
| Heater Option 3 | Harvia KIP 8.0KW Electric with Built-In Controller – Silver |
| Heater Option 4 | Harvia M3 Wood-Burning (sauna stones included) |
| Floor Plan | Available in product documentation |
| Shipping | Free USA Shipping, ships within 1–3 business days |
Ideal For
- Homeowners looking to add a permanent outdoor sauna to their backyard or garden
- Households of 4–6 people who want a shared sauna space
- Those who prefer a wood-burning sauna experience (Harvia M3 option)
- Those who prefer a digitally controlled electric sauna (Harvia KIP 8KW option)
- Buyers who already own a compatible heater and want the kit only
- Indoor sauna installations where a full structural kit is preferred
Important Information
- Electric heater variants require a dedicated electrical circuit. Consult a licensed electrician before installation. Refer to the Harvia heater documentation for full electrical specifications.
- The Harvia M3 wood-burning heater requires proper chimney or flue installation and adequate ventilation. Follow all local building codes and fire safety regulations.
- The no-heater variant is a structural kit only. Heater compatibility and installation are the buyer’s responsibility.
- Outdoor installation requires a level, stable foundation. Refer to the floor plan documentation for foundation and footprint requirements before beginning assembly.
- For indoor installation, outdoor-specific components (roof, exterior siding, metal banding) may be omitted. Review the assembly documentation for indoor configuration guidance.
- The exterior frame is unfinished. Apply an appropriate exterior wood stain or sealant before or shortly after installation to protect the ThermoWood surface.
- Not intended for use by children without adult supervision.
- Consult a qualified healthcare provider before beginning regular sauna use, particularly if you have cardiovascular conditions, circulatory disorders, or other medical concerns.
- Do not use if pregnant without prior medical clearance.
- Always follow the safety guidelines in the included assembly and heater documentation.
Documentation: Floor Plan
(PDF documentation included in product packaging or available upon request.)
Frequently Asked Questions
What heater options are available with this sauna kit?
The kit is available in four configurations: no heater (kit only), Harvia KIP 8.0KW electric with built-in controller in black, Harvia KIP 8.0KW electric with built-in controller in silver, or Harvia M3 wood-burning with sauna stones included. Select your preferred option at checkout.
Can this sauna be installed indoors?
Yes. The kit is designed primarily for outdoor installation, but it can be adapted for indoor use by omitting the outdoor-specific components such as the roof, exterior siding, and metal banding. Refer to the assembly documentation for indoor configuration guidance.
Does the kit include a heater?
Only if you select a heater variant at checkout. The no-heater option includes the full structural kit without a heater. The Harvia KIP 8.0KW and Harvia M3 variants include the respective heater and sauna stones (M3 only) bundled with the kit.
What is ThermoWood and why is it used?
ThermoWood is wood that has been heat-treated at high temperatures to improve its moisture resistance and dimensional stability. This process reduces the wood’s tendency to warp, crack, or absorb water, making it well-suited for permanent outdoor structures exposed to weather and temperature variation.
Does the exterior need to be finished or stained?
The exterior frame is supplied unfinished. It is recommended to apply an appropriate exterior wood stain or sealant before or shortly after installation to protect the surface and achieve your preferred appearance. The unfinished surface accepts most standard exterior wood stains.
What foundation is required for outdoor installation?
The sauna requires a level, stable foundation. Refer to the floor plan documentation included with the kit for specific footprint dimensions and foundation requirements before beginning site preparation.
Does the Harvia M3 wood-burning heater require a chimney?
Yes. The Harvia M3 is a wood-burning heater and requires proper chimney or flue installation and adequate ventilation. All local building codes and fire safety regulations must be followed. Consult a qualified installer before proceeding.
How long does shipping take?
Orders ship within 1–3 business days and are typically delivered within 5–10 business days. Free shipping is included on all orders within the contiguous USA.
The 6-Person Outdoor ThermoWood Cube Sauna Kit is a well-specified, complete structural kit for homeowners who want a permanent outdoor sauna with a clean, modern design. With multiple heater configurations available and an unfinished exterior ready for your preferred stain, it offers a practical starting point for a custom backyard sauna installation. Order today and receive free shipping within 5–10 business days.
This product is intended for general wellness use. It is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease or medical condition. Consult a qualified healthcare provider before use if you have any health concerns.