ThermaSol
ThermaSol is the premium American sauna and steam brand under the Harvia Group, the Finnish heater and wellness conglomerate listed on the Helsinki exchange. The outdoor cabins on this page are built by Kirami in Sastamala, Finland, on the same FinVision production line that supplies Kirami’s European dealers. The indoor cabins are built in the United States. Every cabin ships with a Harvia heater. We carry the full ThermaSol catalog: ten outdoor cabins, four indoor cabins, and Nordic Misty modular add-ons.
The heritage
ThermaSol was founded in 1958 in California by David Altman, who designed the first electric residential steam shower for a Park Avenue apartment. The company moved to Round Rock, Texas in 2014. In July 2024, Harvia Group acquired ThermaSol for $30.4 million, gaining access to ThermaSol’s distribution network of roughly 2,500 plumbing wholesale, kitchen and bath, and design dealers across North America and Europe. The sauna lineup we sell here launched on that same channel as Harvia’s American premium play.
Built in Finland by Kirami
The ten outdoor cabins in this catalog are produced at Kirami’s factory at Villilantie 2, Sastamala, Finland. Kirami opened a dedicated Sauna Factory in November 2020 with approximately 3,000 square meters of heated production space, adjacent to the wood-fired hot tub line Kirami has run for thirty years. Harvia acquired Kirami in May 2021 for EUR 7 million plus an EUR 4 million earnout. The FinVision line carries the Finnish Key Flag Symbol (Avainlippu), the credential that certifies a product as Finnish-designed, Finnish-manufactured, and built from Finnish materials.
The Kirami connection is visible in Kirami’s own image archive: file names follow the pattern kiramibyharvia_kir-XXXX.png across the FinVision production line. Five of our outdoor cabins map directly to Kirami’s catalog: Nordic Misty Small (FinVision S Misty), Nordic Misty Medium (FinVision M Misty), Nordic Dawn (FinVision M Dawn), Solaris Small (FinVision S Zero), Solaris Medium (FinVision M Zero). The other five (Vue, Ombra, Spectra, Fortis, Vera) are additional configurations of the same production line, branded for the American premium market with different glass treatments and exterior wood species. The Ombra ships under Kirami’s internal working name “Velden XL” in non-US markets.
Awards and recognition
Solaris (S Zero / M Zero): Named to TIME’s Best Inventions of 2025 as the world’s first fully self-sufficient off-grid electric sauna.
Vue: 2026 LUXE RED Award and Hospitality Design Awards finalist for its 34-millimeter mirrored thermal glass facade.
The outdoor catalog (built in Finland by Kirami)
Nordic Misty Small: 2 to 4 people, modular system with optional lounges, terraces, pergolas, and changing rooms.
Nordic Misty Medium: 4 to 5 people, same modular system, 9 kW Harvia Virta or Legend 240 wood-burning heater.
Nordic Dawn: 4 to 5 people, full-front double-glazed argon window, heat-treated Finnish pine, 9 kW Harvia Spirit.
Solaris Small: Off-grid solar sauna, 2 to 3 people, triple-pane argon glass, integrated rooftop and wall solar panels.
Solaris Medium: 4 to 5 people, same off-grid solar system.
Vue: 3 to 4 people, Mirror+ glazing transparent by day and mirrored by night, 9 kW Virta.
Ombra: 4 to 5 people, flagship outdoor, IPE Lapacho wave-pattern cladding, natural skylight, private dressing lounge, 10.5 kW Virta.
Spectra: 3 to 4 people, Thermally Modified Tyrol panels, STEICO insulation, Firestone EPDM roof, 8 kW Virta.
Fortis: 3 to 4 people, eave-style roofline, brushed Tyrol facade, 8 kW Virta.
Vera: 2 to 3 people, smallest outdoor footprint (63 by 87 inches), dual mirrored Parsol glass walls, 8 kW Virta.
The indoor catalog (built in the USA by ThermaSol)
Aalto: Named for Finnish architect Alvar Aalto. 3 to 4 people, Brushed Tyrol walls, RGB color-therapy LEDs, 9 kW Virta.
Astra: 3 to 4 people, disciplined glass-panel front for primary baths, 9 kW Virta.
Lumaria Medium: 2 to 3 people, panoramic transparent glass front, 9 kW Virta.
Lumaria Large: 4 to 5 people, same construction in a larger footprint.
Why we carry ThermaSol
The American premium sauna market has been culturally Finnish for years, but most cabins arriving in American backyards have been built in Estonia (Auroom) or Germany (Klafs). The ThermaSol lineup closed that loop: the outdoor cabins are now built in Finland, by a Finnish manufacturer, with Finnish heaters, and shipped through a 2,500-dealer American distribution network. There is no other premium American sauna brand with this combination of provenance and reach.
Every cabin in this catalog ships with free shipping, a Harvia heater pre-wired at the factory, and access to our Bens-on-site installation program when scheduling aligns. We carry the full lineup, we know the construction in detail, and we will tell you the trade-offs (Solaris winter solar yield, forklift logistics, lead times) before you order rather than after.
Frequently asked questions
Are ThermaSol outdoor saunas really made in Finland? Yes. The ten outdoor cabins on this page are built at Kirami’s factory in Sastamala, Finland, on the same FinVision production line that supplies Kirami’s European customers. Final delivery and installation happen in the United States.
Who is Kirami? Kirami is a Finnish wood-fired hot tub and sauna manufacturer founded in 2001, based in Sastamala. Harvia Group acquired Kirami in May 2021. Kirami opened a dedicated Sauna Factory in November 2020 and has been shipping FinVision cabins to European dealers ever since.
What is the warranty on a ThermaSol outdoor cabin? The Nordic Misty Small and Medium carry a 2-year warranty. The other outdoor cabins (Nordic Dawn, Solaris Small/Medium, Vue, Ombra, Spectra, Fortis, Vera) carry a 1-year warranty. Heaters carry the standard Harvia 1-year warranty. Indoor cabins carry a 1-year warranty.
Does ThermaSol still sell steam generators? Yes. ThermaSol’s original product line is residential steam generators and steamhead systems. The sauna cabin lineup is a 2024 launch and runs alongside the steam catalog. We focus on the sauna cabins on saunamarketplace.com.
Is the ThermaSol indoor line also Finnish-built? The indoor cabins (Aalto, Astra, Lumaria Medium/Large) are built in the United States by ThermaSol. They ship as components for on-site assembly rather than as the fully-assembled outdoor modules.
ThermaSol Ombra | Prebuilt Outdoor Sauna by Harvia
$75,028.00This is the cabin Kirami builds when they want to show what Kirami can do. Named for the Italian word for shadow, The Ombra is the largest outdoor in the ThermaSol line: 130 inches long, four to six people, full-height Stopsol Bronze glass walls with a natural skylight. Thermally Modified Ipe Lapacho exterior, Canadian Hemlock interior with brushed Tyrol panels and Aspen benches. 10.5 kW Harvia Virta with Wi-Fi, CX45 controller, sloped weatherproof roof. Twelve-week build, free shipping included.
ThermaSol Medium Solaris Sauna Cabin | Hybrid or Solar Powered Sauna
$70,714.00The cabin you’d hand your kids twenty years from now. The Solaris is Kirami’s solar-powered, off-grid electric sauna line, named to TIME’s Best Inventions of 2025. The Medium is the bigger of the two cabins in the line: a 3 kW Harvia KIP heater running off rooftop solar and a battery bank, with no electrical service to maintain. 86 by 86 inches, four to five people, 415 cu ft. Tile Oak cladding inside and out, Brushed Alder benches, solar-tinted panoramic glass, RGB LED light therapy. Built in Finland by Kirami. Twelve-week build, shipping included free.
ThermaSol Vue Sauna Cabin | 9.0 kW
$51,071.00A glass front that reads two ways. Named for the French word for view, the Vue won the 2026 LUXE RED Award and was named a finalist in the Hospitality Design Awards. The Vue’s 34mm Mirror+ glazing is transparent during the day and a privacy mirror at night, which is the spec that makes a glass-front outdoor cabin practical for a yard with neighbors. 87 by 79 inches, three to four people, 354 cu ft. 9 kW Harvia Virta with Wi-Fi, CX45 controller. Rustic Tyrol interior with Aspen benches. Pick door side at checkout. Built in Finland by Kirami. Twelve weeks to build, ships free.
ThermaSol Spectra Sauna Cabin | 8.0 kW
$36,092.0034mm Parsol dark grey glass, 8 kW Harvia Virta, one configuration. The Spectra is the Cube cabin for buyers who do not want to spec a cabin. Finished entirely in Thermally Modified Tyrol panels, 90 by 82 inches, three to four people, 389 cu ft. Wi-Fi controller, RGB LED light therapy, Firestone EPDM roof, multi-layer insulated walls, black aluminum frame. No door-side choice, no heater swap. Twelve weeks Finland-built, free shipping.
ThermaSol Vera Sauna Cabin | 8.0 kW
$49,101.00Want a real sauna on a small balcony or a rooftop? The Vera is sized for that. Inspired by the Italian word veranda, the Vera packs panoramic glass into the smallest outdoor footprint in the line. 87 by 63 inches, two to three people, 282 cu ft, with dual 34mm Parsol dark grey mirrored glass walls inside a black enamel frame. 8 kW Harvia Virta heater with Wi-Fi, CX45 controller. Thermally Modified Tyrol interior, Aspen benches, multi-layer insulated walls. Pick door side at checkout. Built in Finland by Kirami. Twelve-week build, free shipping included.
ThermaSol Medium Lumaria Sauna Cabin | 9.0 kW
$21,276.00Two to three regulars, indoor footprint. The Lumaria Medium is the mid-size ThermaSol indoor: 86.6 by 66.9 inches, 278 cu ft, with a transparent panoramic glass front and a 9 kW Harvia Virta paired with the CX45 controller. Brushed Tyrol panel walls, 24-inch Thermo-Aspen benches. Lives inside a finished room: no foundation pour, no demo. Pick door side at checkout. Designed and crafted in the USA by ThermaSol. Four-to-eight-week build, free shipping.
ThermaSol Large Lumaria Sauna Cabin | 9.0 kW
$23,648.00Honest take: most indoor sauna kits do not look like the renderings. The Lumaria Large is the exception. ThermaSol’s biggest indoor footprint, 86.6 by 86.6 inches, 360 cu ft, four to five people. Brushed Tyrol panel interior with Thermo-Aspen benches, panoramic transparent glass front, 9 kW Harvia Virta paired with the CX45 controller. Flat-packed for a finished-room install with no drywall demo. Pick door side at checkout. Four-to-eight-week build, free shipping included.
ThermaSol Nordic Misty Small Sauna Cabin
Price range: $31,883.00 through $32,583.00For the buyer with a side yard and two or three regulars, the Nordic Misty Small is the right Kirami footprint. 91 by 60 inches, 316 cubic feet, heat-treated spruce exterior, heat-treated aspen interior. Tinted panoramic glass front. Choose door side and heater at checkout: 6 kW Harvia Spirit electric with Wi-Fi or Legend 150 wood-burning. CX45 controller, plug-and-play wiring. Distributed by ThermaSol. Twelve-week lead time, ships free.
ThermaSol Small Solaris Sauna Cabin | Solar Off-Grid
$66,645.00Most outdoor saunas require a 240V trench. This one does not. The Solaris Small is the world’s first solar-powered, off-grid electric sauna: 3 kW Harvia KIP heater running off integrated rooftop panels and an onboard battery bank. Named to TIME’s Best Inventions of 2025 list. 86 by 60 inches, two to three people, Tile Oak cladding inside and out, Brushed Alder benches, solar-tinted panoramic glass, RGB LED therapy. No chimney, no service drop, no wood pile. Built in Finland by Kirami. Twelve-week build, ships free.
ThermaSol Nordic Dawn Prebuilt Sauna
$33,467.00Does the heater sound like a leaf blower when it ramps up? Not the Spirit. The Nordic Dawn is built around Harvia’s quieter 9 kW Spirit element paired with the Wi-Fi-enabled CX45 controller, so a cabin within earshot of the house stays bearable. 86.8 by 85.4 inch footprint, 424 cu ft, four to five people. Heat-treated spruce exterior, aspen interior, full glass front. Built in Finland by Kirami. Twelve-week build, free shipping included.
ThermaSol Fortis Sauna Cabin | 8.0 kW
$36,619.00Honest disclosure: most outdoor cabins are spec’d for a mild fall, not a Manitoba winter. The Fortis is built differently. Thicker multi-layer insulated walls, full Thermo-Aspen framing, 8 kW Harvia Virta heater rated for repeated minus-thirty cycles. 90 by 87 inches, three to four people, dark grey glass front with hidden-hinge aluminum frame. Heat-treated spruce exterior. Built in Finland by Kirami. Twelve weeks to build, free shipping.
ThermaSol Astra Sauna Cabin | 9.0 kW
$23,604.00Hall closet or guest-room corner? The Astra is the indoor ThermaSol model built for households that have closet-conversion space rather than a dedicated room. 85.4 by 85.4 inches with corner glass and an L-bench, so it tucks into a finished-basement nook. Same 9 kW Harvia Virta as the larger Aalto in 350 cu ft, so heat-up is faster. Brushed Tyrol panel interior, Thermo-Aspen benches, CX45 controller. Pick door side at checkout. Four-to-eight-week build, free shipping.
ThermaSol Aalto Sauna Cabin | 9.0 kW
$23,455.00Named for Finnish architect Alvar Aalto, the cabin is ThermaSol’s design-forward indoor option. The Aalto is an indoor sauna sized for transformation: 87 by 87 inches, 83 inches tall, drops into a finished basement or spa room without drywall demo or a foundation pour. Full-height transparent panoramic glass front, 9 kW Harvia Virta behind safety rails, brushed Tyrol panel interior with Thermo-Aspen benches. Pick door side at checkout. Designed and crafted by Finland’s best, most experienced team.
ThermaSol Nordic Misty Medium Sauna Cabin
Price range: $35,644.00 through $36,062.00Tinted glass, four-to-six bench, Finnish build. The Nordic Misty Medium is Kirami’s pre-cut outdoor cube with floor-to-ceiling Parsol glass and a Harvia heater wired at the factory. 91 by 87 inches, heat-treated spruce exterior, heat-treated aspen interior. Choose door side and heater at checkout: 9 kW Harvia Virta electric with Wi-Fi or Legend 240 wood-burning. CX45 controller, plug-and-play wiring. Twelve-week Finnish build, free shipping.
Prebuilt
Sauna Brushes
Vents