Well designed ventilation is crucial


  • Complete air exchange
  • No unpleasant draught
  • Quick dehumidification with third ventilation duct

Proper air exchange is what makes a pleasant hot air or warm sauna bath. The oxygen level in the air should be high, but the air exchange should not noticeably cool the air or cause an unpleasant draught.

RUKU’s Thermium cabins and Finnish sauna cabins are built with our efficient, patented ventilation system. The system ensures air exchange in every corner of a cabin without causing a draught.

Two ventilation ducts enable continuous air exchange. When necessary, a third ventilation duct can be opened for rapid air exchange, and a cabin can be quickly dehumidified after a steam bath.


RUKU developed an efficient ventilation system with three air ducts (3K-vent-section).

The following features differentiate the system from a conventional air discharge duct:
Air can be discharged at the top or the base of a duct, either simultaneously or separately, depending on demand.

A 3K-vent-Section is part of the cabin wall’s section pattern and can be placed strategically for optimum airflow; if necessary more than one section can be incorporated in the walls of a cabin. The inside and outside cladding of a 3K-vent-section are flush with the wall, the section neither obstructs internal furnishing nor diminishes the outside appearance of the cabin.