
Faster sauna heating
A well-insulated sauna heats up faster and is energy efficient. PIR is a rigid thermal insulation material and one of the most efficient insulation materials currently available. Because PIR performs so well in insulating heat, it’s the preferred material at Harvia.
PIR is cut into insulation boards and used within the internal walls and ceiling of Harvia’s highly-customisable Block and Ventura sauna cabins. Because it’s such an excellent insulator, PIR requires half the usual thickness of other insulation materials to reach the same level of thermal performance. Harvia uses 30mm thick PIR insulation boards which is equivalent to approximately 60mm of conventional rock wool insulation.
A faster-heating sauna means you can start enjoying the healing benefits of heat sooner whilst also saving on the costs of energy.

Moisture-resistant insulation
Whilst sauna habits vary, many people enjoy the feeling of löyly – the steam created when you throw water onto the rocks of the sauna heater. This creates humidity. As such, the insulation of the sauna must be moisture-resistant to ensure it remains dry and long-lasting.
PIR is highly water resistant because of its compact cell structure. The hydrophobic, compact cell structure of PIR means that it doesn’t shrink, expand or mold.
Here at Harvia we use foil-coated PIR insulation boards. The foil coating provides the PIR insulation boards with excellent moisture resistance and further improves their performance.

Made to last
Insulation that shrinks and expands with the fluctuating heat will, over time, undermine and weaken the structure of the sauna. Constant shifts in temperature can cause insulation materials other than PIR to leak energy. This wastes money and means the heating of the sauna is slower and less effective.
PIR tolerates heat fluctuations well which makes it a great choice for a sauna structure. PIR is a rigid material with tightly-packed cells which mean it cannot shrink or expand. This also means the structure of the sauna remains strong and will endure for many years to come.