A Refined 3–4 Person Retreat with Smart Heat & Ambient Lighting

Bring a sophisticated outdoor wellness experience into your backyard with the ThermaSol Fortis Outdoor Sauna Cabin. Designed to accommodate 3–4 people, Fortis combines a contemporary architectural profile with thermally modified Nordic spruce and pinewood, thermally modified aspen benches, dark grey Parsol glass, and integrated RGB lighting.

The fully enclosed cabin is insulated for all-season outdoor use, with a modern eave-style roofline and a large glass façade that creates a bright yet private environment. Its 8mm Parsol Dark Grey Glass, aluminum framing, and hidden hinges give the exterior a clean architectural finish.

Fortis is equipped with an 8kW Harvia Virta heater with Wi-Fi, providing traditional sauna heat and the option to add water to hot stones for increased humidity. The cabin arrives fully assembled, making this a premium turnkey outdoor sauna rather than a conventional DIY kit.

Why You’ll Love It

• 3–4 Person Capacity — A generously sized cabin designed for shared sauna sessions with family or friends.
• Thermally Modified Wood Construction — Thermally modified Nordic spruce/pine forms the exterior, while thermo-aspen is used for the interior walls and benches.
• 8kW Harvia Virta Heater with Wi-Fi — Provides powerful, even heat with connected control capabilities.
• Dark Grey Parsol Glass — 8mm dark grey glass creates a contemporary look while adding privacy and solar protection.
• RGB LED Color Lighting — Integrated lighting with remote control lets you customize the cabin's ambiance.
• Multi-Layer Wood-Fiber Insulation — Helps retain heat and supports the cabin's all-season outdoor design.
• Fully Assembled Delivery — Fortis arrives pre-assembled for placement at the prepared installation site.
• 24-Inch Bench Depth — The published specification provides generous bench depth for a comfortable seating area.

Designed for Year-Round Outdoor Wellness

Fortis is built specifically as an outdoor sauna cabin, with construction intended for gardens, patios, and backyard wellness spaces. Its insulated walls and durable roof are designed to support comfortable use through changing seasons while its enclosed architecture provides privacy from the surrounding outdoor environment.

Unlike smaller portable sauna products, Fortis arrives as a substantial pre-assembled cabin. This gives it the visual presence of a permanent architectural feature while reducing the assembly work required on site.

Nordic Spruce & Thermo-Aspen Construction

The exterior uses thermally modified and brushed Nordic spruce/pinewood, while the interior uses thermally modified aspen for the walls and benches. This combination creates a contrast between the textured exterior and the smoother, warm-toned interior seating area.

Contemporary Parsol Glass Front

Fortis features 8mm Parsol Dark Grey Glass with hidden aluminum framing. The dark glazing contributes to the modern appearance while providing greater visual privacy than standard clear glass.

The glass door uses an aluminum frame with hidden hinges, maintaining the streamlined exterior design.

8kW Harvia Virta Heat

The Fortis package is specified with an 8kW Harvia Virta heater with Wi-Fi. The Virta is a traditional sauna heater designed to provide even heat, with heating elements separated from the stones to reduce wear. Water can be added to the hot stones to create the classic Finnish löyly experience.

Smart Control & Wi-Fi

Current dealer specifications identify the Harvia Xenio CX45 Wi-Fi control system with the Fortis package, allowing temperature and sauna functions to be managed through the connected control system.

There is a source discrepancy worth noting: ThermaSol's current product page describes smart control options, while its separate Virta page states that the Xenio Control Kit is required and sold separately for the standalone heater. Authorized-dealer Fortis package listings specifically identify the CX45 as included, so the final Shopify variant/package should be confirmed with the supplier before publication.

RGB Ambient Lighting

Integrated RGB LED color lighting with remote control is part of the Fortis specification. This allows the interior ambiance to be adjusted for different preferences and evening sessions.

Product Specifications

*CX45 inclusion is supported by current dealer package listings, while ThermaSol's current pages describe smart-control availability more generally. Confirm the exact package configuration before final Shopify publication.

What's Included

Current package listings identify:

• Pre-assembled Fortis sauna cabin
• Harvia Virta 8kW Wi-Fi heater
• Harvia Xenio CX45 Wi-Fi control
• Harvia AC3020 sauna stones, 3 boxes
• RGB LED lighting with remote
• Installation instructions

ThermaSol's current product page specifically identifies the Virta heater as included, while the exact control and stone package should be confirmed against the purchased configuration.

Shipping & Delivery

Fortis is delivered fully assembled by flatbed trailer. ThermaSol states that customers are notified approximately two weeks before the scheduled delivery to prepare the site. A forklift or crane is required for unloading, and manual offloading is not recommended due to the unit's size and weight.

Current dealers report lead times ranging from approximately 3–6 weeks to 4–8 weeks, depending on supplier and order timing. This should be confirmed at the time of purchase rather than treated as a fixed promise.

Installation & Site Preparation

Fortis does not require on-site cabin assembly. It arrives fully assembled and is placed on a properly prepared foundation.

ThermaSol recommends a firm, level surface with slight runoff for drainage, including concrete, decking, pavers, or compacted gravel. The delivery path must be accessible to the forklift or crane needed for placement. A licensed electrician must complete the heater installation.

Outdoor Installation Considerations

Fortis is designed exclusively for outdoor use. It is intended for locations such as gardens, patios, and backyard wellness spaces.

Allow sufficient room around the cabin for delivery equipment, door access, maintenance, drainage, and safe heater operation. The fully assembled unit weighs approximately 2,161 pounds, making site access and unloading logistics an important part of installation planning.

Care & Maintenance

ThermaSol's current care guidance recommends regularly wiping down the sauna benches, periodically cleaning exterior buildup, and inspecting the sauna stones annually for cracking or brittleness.

Follow the manufacturer's maintenance instructions for the wood surfaces, glass, heater, controls, lighting, roof, and drainage system.

Warranty

Current authorized-dealer documentation indicates a 1-year limited warranty for the ThermaSol sauna room/structure, while Harvia heater and Xenio control components may carry longer residential warranties depending on the component. One current dealer specifies 5 years for the Harvia heater and Xenio controls/power box, with 1 year for stones and heating elements.

Warranty terms can vary by application and dealer, so the final sale should reference the applicable current ThermaSol/Harvia warranty documentation.

Safety & Usage Information

Fortis should be installed and operated according to the supplied ThermaSol and Harvia documentation.

The heater requires professional electrical installation, and ThermaSol specifically states that a licensed electrician must install the heater.

The sauna can be used in the traditional Finnish manner by adding an appropriate amount of water to the hot stones to create humidity. Use only according to the heater manufacturer's instructions.

The wellness claims in the original draft have been moderated. Fortis should be marketed around relaxation, traditional sauna bathing, comfort, and outdoor wellness, rather than guaranteed medical or therapeutic outcomes.

Wellness Applications

The ThermaSol Fortis is well suited to:

• Backyard sauna retreats
• Shared family sauna sessions
• Couples and friends
• Outdoor wellness spaces
• Traditional Finnish sauna bathing
• Post-exercise relaxation
• Premium patio and garden projects
• Year-round outdoor relaxation

Why Choose Wellness Edge Frontier?

Wellness Edge Frontier brings together premium wellness products for customers creating sophisticated spaces for relaxation, self-care, and everyday well-being.

The ThermaSol Fortis Outdoor Sauna Cabin combines a substantial 3–4 person capacity, premium thermally modified woods, dark Parsol glass, integrated RGB lighting, advanced insulation, and an included 8kW Harvia Virta heater in a fully assembled outdoor cabin.

Frequently Asked Questions

How many people does the Fortis accommodate?
ThermaSol specifies a capacity of 3–4 people.

Is Fortis an indoor or outdoor sauna?
It is designed exclusively for outdoor use.

What are the dimensions?
The approximate exterior dimensions are 90" L × 87" W × 89" H.

What is the assembled weight?
ThermaSol lists an approximate assembled weight of 2,161 pounds and shipping weight of 2,381 pounds.

What type of wood is used?
The exterior uses thermally modified and brushed Nordic spruce/pinewood, while the interior uses thermally modified aspen.

What type of glass does Fortis use?
It uses 8mm Parsol Dark Grey Glass with aluminum framing and hidden hinges.

What heater is included?
ThermaSol specifies an 8kW Harvia Virta heater with Wi-Fi.

Does the sauna create steam?
It provides a traditional sauna experience where water can be added to the hot stones to create humidity. It is not a separate steam-shower system with a dedicated steam generator.

Does it include RGB lighting?
Yes. Integrated RGB LED color lighting with remote control is specified.

Does it arrive assembled?
Yes. Fortis is delivered fully assembled via flatbed.

Is a crane or forklift required?
Yes. ThermaSol states that a forklift or crane is required for unloading and placement, and manual offloading is not recommended.

Does it include the Xenio control?
Current authorized-dealer Fortis packages list the Harvia Xenio CX45 Wi-Fi control, but ThermaSol's current standalone Virta documentation says the Xenio Control Kit is separately required/sold for the heater. Verify the exact purchased package before treating the controller as included.