Named for the word spectrum celebrating light, colour, and artistic form the ThermaSol Spectra Sauna Cabin is a compact, design-forward outdoor sauna that refuses to blend in. Its entire front face is Parsol Dark Grey thermal glass: a rich, dark grey-green tinted glass that actively filters solar radiation and provides diffuse privacy from outside, while filling the interior with soft, even natural light. Framed in black aluminum and clad in thermally modified Tyrol wood panels, the Spectra makes a confident modern statement in any garden setting then backs it up with a Harvia 8kW Virta heater, STEICO wood fiber insulation, a Firestone EPDM roof, and RGB LED colour therapy, all arriving in a single fully assembled delivery.
Parsol Dark Grey Glass solar protection, diffuse privacy, natural light
The Spectra's 34mm Parsol Dark Grey Glass (PSDG) is a different glass technology from the Vue's mirror system and it creates a different experience. Where mirror glass reflects the exterior completely, Parsol Dark Grey tinted glass filters and softens incoming light, reducing solar heat gain and glare while allowing a gentle, even diffusion of natural daylight into the sauna interior. From outside, the dark grey tone provides meaningful visual privacy across most angles. From inside, bathers are aware of the outdoor environment without the full panoramic transparency of untinted glass a more enclosed, meditative quality of light that suits long sessions and focused relaxation. The 34mm thickness adds genuine thermal insulation to the glass layer, working in tandem with the STEICO wall insulation to maintain consistent interior temperatures.
Thermally modified Tyrol wood exterior and interior
The Spectra uses thermally modified Tyrol wood panels on both the exterior cladding and the interior walls an unusual design choice that creates a warm, cohesive character throughout. The exterior Tyrol panels provide natural weather resistance without paint or chemical treatment, and their grain and texture give the Spectra a warmer, more organic character than a purely glass or metal exterior. The interior brushed Tyrol panel walls complement the thermo-aspen benches a combination of two characterful natural materials that make the inside of the Spectra feel genuinely handsome rather than purely functional. The black aluminum framing at the glass-to-wood transitions adds precision and architectural sharpness to the design.
STEICO wood fiber insulation named-brand, eco-friendly, high performance
Where many outdoor sauna manufacturers describe their insulation generically, the Spectra specifies it by name: STEICO wood fiber insulation. STEICO is a leading European manufacturer of sustainable building insulation, producing wood fiber panels from byproducts of the timber industry. Wood fiber insulation has excellent thermal mass it absorbs heat slowly and releases it slowly, maintaining more stable interior temperatures during and between sessions than mineral wool or foam alternatives. It is also hygroscopic, managing moisture vapour within the wall system in a way that suits the humid environment of a sauna particularly well. Multi-layer construction wraps the STEICO panels through the walls, floor, and ceiling of the Spectra for a complete thermal envelope.
Firestone EPDM roof commercial-grade flat roofing, fully weatherproof
The Spectra's flat roof is finished with a Firestone EPDM membrane one of the most respected single-ply rubber roofing systems in the commercial construction industry. Firestone EPDM is highly durable, remains flexible at extreme cold temperatures, resists UV degradation and ozone, and provides a watertight seal that does not require periodic resealing or maintenance. It is the same roofing approach used on commercial flat roofs designed to perform for decades without intervention. On the Spectra, it provides year-round weather protection in any climate heavy rain, snowload, and temperature cycling without any seasonal preparation or roof maintenance required.
Harvia 8kW Virta with Wi-Fi and RGB LED colour therapy
The Spectra ships with the Harvia Virta 8kW electric heater fully installed sized precisely for the Spectra's 3–4 person cabin volume. Wi-Fi connectivity via the Harvia app allows you to preheat the Spectra remotely so it is at temperature the moment you are ready to step in. The Virta's black stainless-steel body, front-facing maintenance hatch, and separated heating elements and stones extend the heater's operational lifespan significantly compared to designs where elements and stones share the same thermal space. RGB LED colour therapy lighting is integrated throughout the interior, with the full spectrum controllable via the included remote from warm amber to cool blue, adjusted to any mood the session requires.
A 3-4 person fully assembled outdoor sauna with a 34mm Parsol Dark Grey tinted glass front in black aluminum framing, thermally modified Tyrol wood panels on exterior and interior walls, thermo-aspen benches, multi-layer STEICO wood fiber insulation, Firestone EPDM flat roof, Harvia 8kW Virta heater with Wi-Fi app control, and RGB LED colour therapy with remote. Left or right entrance. Arrives fully assembled via flatbed. Made to order. Designed and built in USA. 1-year warranty.
3–4 people Fully assembled - turnkey 34mm Parsol Dark Grey tinted glass Black aluminum framing Solar protection + diffuse privacy Thermally modified Tyrol wood exterior Tyrol wood panel interior (brushed) Thermo-aspen benches + backrest STEICO wood fiber insulation Firestone EPDM roof Harvia 8kW Virta Wi-Fi heater included RGB LED colour therapy + remote Left or right entrance Designed & built in USA 1-year warranty
Specifications
Dimensions
| Exterior width |
82" (2,083 mm) |
| Exterior depth |
90" (2,286 mm) |
| Exterior height |
91" (2,311 mm) |
| Capacity |
3-4 people |
| Entrance |
Left or right - select at order |
Glass & exterior
| Glass type |
34mm Parsol Dark Grey Glass (PSDG) |
| Glass privacy |
Dark grey tinted - diffuse privacy + solar protection |
| Glass frames |
Black aluminum - architectural, UV resistant |
| Exterior cladding |
Thermally modified Tyrol wood panels |
| Roof |
Firestone EPDM flat, commercial-grade, fully waterproof |
| Origin |
Designed, engineered, and built in USA |
Interior & construction
| Interior walls |
Thermally modified Tyrol wood panels (brushed) |
| Benches |
Thermally modified aspen upper and lower |
| Backrest |
Thermally modified aspen |
| Insulation |
Multi-layer STEICO wood fiber eco-friendly, high performance |
| Use |
Year-round outdoor all climates |
| Foundation |
Firm, level surface with slight drainage runoff required |
Heating, lighting & control
| Heater |
Harvia Virta 8kW freestanding electric |
| Heater control |
Wi-Fi app remote preheat, temperature, scheduling |
| Heater body |
Black stainless steel front maintenance hatch |
| Sauna stones |
Included with heater |
| Löyly (steam) |
Yes add water to stones for traditional steam |
| Lighting |
RGB LED colour therapy full spectrum |
| Light control |
Included remote controller |
| Heater circuit |
240V / 1-phase hardwired (licensed electrician required) |
Delivery & installation
| Delivery condition |
Fully assembled turnkey-ready |
| Delivery method |
Flatbed trailer curbside |
| Off-loading |
Forklift or crane required manual not recommended |
| Site notification |
2 weeks prior to scheduled delivery |
| On-site assembly |
None place and connect electrician only |
| Lead time |
12–13 weeks (made to order) |
| Warranty |
1 year |
Spectra Sauna Cabin - Dimensions
What's included
Fully assembled Spectra Sauna Cabin
34mm Parsol Dark Grey tinted glass front (PSDG)
Black aluminum framing
Thermally modified Tyrol wood exterior panels
Brushed Tyrol wood panel interior walls
Thermo-aspen upper bench
Thermo-aspen lower bench
Thermo-aspen backrest
Multi-layer STEICO wood fiber insulation
Firestone EPDM flat roof
Glass entry door (left or right selected at order)
Harvia Virta 8kW electric heater
Sauna stones
Wi-Fi heater control + Harvia app compatibility
RGB LED colour therapy lighting system
LED remote controller
Full electrical pre-wiring
Installation manual
Why the Spectra stands out
34mm Parsol Dark Grey glass
Dark grey tinted glass that filters solar heat and glare, provides diffuse outdoor privacy, and fills the interior with soft, even natural light a calmer, more meditative quality of light than clear panoramic glass delivers.
Tyrol wood exterior and interior
Thermally modified Tyrol wood panels on both sides of the wall create a cohesive, warm character throughout. The exterior panels weather beautifully without treatment; the interior brushed panels contrast naturally with the aspen benches.
STEICO wood fiber insulation
Named-brand, eco-friendly European wood fiber insulation with excellent thermal mass heats up efficiently, retains heat between sessions, and manages moisture vapour within the wall system. Multi-layer construction, floor to ceiling.
Firestone EPDM roof
Commercial-grade single-ply rubber roofing the same system specified on flat commercial roofs built to last decades. UV-stable, cold-flexible, and fully waterproof with no seasonal maintenance or periodic resealing required.
Harvia 8kW Virta with Wi-Fi
Premium Harvia Virta heater black stainless steel, front maintenance hatch, separated elements and stones for longevity. Wi-Fi app control for remote preheating from anywhere. Löyly-compatible: add water to stones for traditional steam.
RGB LED colour therapy
Full-spectrum RGB LED lighting adjustable to any colour and intensity via the included remote. Shift from warm amber to energising green to cool blue or any shade across the spectrum for every session, every mood.
About ThermaSol
American design & engineering
65+ years of steam and sauna expertise colour, light, and artistic form.
ThermaSol has been engineering premium steam and sauna systems since 1958. The Spectra is named for spectrum the full range of light and colour and it earns that name through the combination of its Parsol Dark Grey glass, RGB LED colour therapy system, and thermally modified Tyrol wood that responds to different qualities of light at different times of day. This is a sauna built around the idea that the experience of colour and light is as much a part of wellness as heat and steam.
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34mm Parsol Dark Grey Glass solar protection, diffuse privacy, soft natural light
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Black aluminum framing precise, modern, UV and corrosion resistant
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Tyrol wood exterior and interior thermally modified, warm, natural character
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STEICO wood fiber insulation named-brand, eco-friendly, excellent thermal mass
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Firestone EPDM roof commercial-grade, decades of flat-roof performance
About ThermaSol
Designed and built in the USA where performance meets design intention
ThermaSol designs every product with a specific design intention not just a material list. For the Spectra, that intention is the interplay of light, colour, and natural warmth. The Parsol glass, the Tyrol wood, the STEICO insulation, and the RGB LED system are not arbitrary choices. They are a coherent response to the question of what a modern outdoor sauna should look and feel like when the light changes, the season changes, and the mood of each session is its own.
The Spectra arrives via flatbed trailer completely assembled. ThermaSol notifies customers two weeks before the scheduled delivery date. A forklift or crane is required for off-loading the path from the delivery vehicle to the placement site must be clear and accessible, and the foundation must be firm and level with slight drainage runoff. A licensed electrician must connect the Harvia Virta heater to the 240V circuit before the first session.
Manuals & Documents
Everything you need before and after installation
Download the ThermaSol Spectra Sauna Cabin installation manual below. It covers site preparation, foundation and drainage requirements, placement and clearance specifications, electrical connection for the Harvia Virta heater, RGB LED setup, and ongoing maintenance guidance for the Parsol glass, Tyrol wood panels, and Firestone EPDM roof. Review it before your delivery appointment to ensure the site is correctly prepared and the electrical contractor is briefed on the circuit requirements in advance.
Installation Guide
Warranty
1-year ThermaSol warranty
The ThermaSol Spectra Sauna Cabin is covered by ThermaSol's 1-year limited warranty, covering defects in materials and workmanship under normal residential use for one year from the date of delivery to the original purchaser. ThermaSol will, at its discretion, repair or replace any covered defective component at no cost. The warranty does not cover damage from improper installation, misuse, abnormal weather events, inadequate foundation or drainage, or failure to follow ThermaSol's published installation guidelines. The Harvia Virta heater is covered under Harvia's separate manufacturer warranty. Proof of purchase from an authorized dealer is required for all warranty claims. We are an authorized ThermaSol dealer.
