HUUM Rolls Out Air Tunnel Upgrade Across Its Entire Heater Line
The Estonian manufacturer has made its internal air tunnel a standard feature in all HIVE models, improving heat-up time and protecting heating elements from stone weight.
HUUM, the Estonian sauna heater manufacturer known for its sculptural designs, has completed a significant but understated engineering upgrade. Starting in early 2024, the company made its internal air tunnel a standard feature across all HIVE models. The HIVE Mini followed in 2025. It's the kind of improvement that doesn't photograph well but matters to anyone who cares about heater longevity and steam quality.
What the Air Tunnel Does
The air tunnel is a structural channel inside the heater body that separates the heating elements from the weight of the stones above. This does two things: it improves airflow through the stone chamber, which speeds up heat delivery and improves steam quality when water is thrown on the rocks, and it protects the elements from being crushed or warped by the mass of stones sitting on top of them.
HUUM says the upgrade reduces heat-up time by roughly 15-20% and should meaningfully extend element lifespan, which has historically been one of the main maintenance costs for heater owners.
The upgrade also applies to HUUM's DROP series, the wall-mounted heater line that starts around $850 for the 4.5kW model. HUUM controls all heater connectivity through its proprietary UKU WiFi controller and companion app.
We believe the sauna heater should be the intelligence center of the room, not just the heat source.
Market Context
HUUM has been one of the fastest-growing heater brands in the North American market, built on a combination of striking industrial design (the HIVE's beehive silhouette is instantly recognizable) and competitive pricing for the quality level. The air tunnel upgrade keeps the exterior design unchanged while improving the internals, a move that rewards existing fans rather than chasing headlines.
Founded by Siim Nellis, a third-generation Estonian sauna heater maker, HUUM competes in the premium segment against Harvia, Narvi, and IKI from Finland and the TyloHelo brands from Sweden. The company later expanded its line with the HUUM Core, a bench-embeddable heater that launched in the US in 2026.
Arlene Scott
Senior Wellness Correspondent & Hospitality Consultant
Arlene Scott brings over fifteen years of reporting and consulting experience across energy infrastructure, sustainable design, and thermotherapy-focused hospitality.
Full byline
Arlene Scott is a Senior Wellness Correspondent for SaunaNews.com, bringing over fifteen years of experience at the intersection of energy infrastructure, sustainable design, and thermotherapy. Her work focuses on the physiological benefits of passive heat therapies and the sustainable integration of sauna culture into modern wellness routines.
Arlene's background is rooted in the clean energy transition. She was a founding writer at MicrogridMedia.com, where she covered the technical and economic viability of desalination projects, microgrid deployments, and distributed renewable energy systems. During the mid-2010s, she was a regular contributor to Greentech Media (GTM) during its independent era — prior to the Wood Mackenzie acquisition in 2016 — reporting on the early integration of thermal energy storage and sustainable infrastructure.
Transitioning her focus from macro-energy systems to human-scale wellness, Arlene now applies her technical background to the hospitality sector. She operates as an independent consultant, advising boutique hotels and eco-resorts on the design, energy efficiency, and historical authenticity of commercial sauna and thermal spa installations. Her consulting work ensures that high-end wellness facilities balance traditional Nordic bathing principles with modern sustainable engineering.
Arlene holds a specialized certification in Applied Thermic Wellness from the Nordic Institute of Passive Heat Studies (NIPHS) and is a recognized associate member of the International Sauna Association (ISA). When she isn't reviewing the latest innovations in infrared technology or consulting on a new resort project, Arlene can be found tending to her own traditional wood-fired sauna in the Pacific Northwest. You can read her complete archive of essays on energy, wellness, and sustainable living at www.arlenescott.com.
