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Using ThermoWoods in Saunas and for Hot Tubs

Image: Dimitris Kiriakakis

Thermally-modified timber (ThermoWood) is an extremely durable, stable and lightweight timber and has often been selected to be used in the creation of saunas and hot tubs. ThermoWood timber has been acclaimed to be one of the best materials for the manufacturing of saunas and hot tubs, as well as for decoration and cladding. This is due to their excellent performance and decorative properties.

Since the moisture content of the timber during the heat treatment process has been almost eliminated, the risk of mould formation is radically reduced. Offering minimal maintenance needed to preserve the hot tub’s appearance. This also makes the hot tub more weather and rot-resistant. The process is also natural, meaning it has no detrimental impact on the environment as no chemicals or additives are used to improve the performance of the timber.

The thermal-modification process improves the insulation properties of the timber by 30%. Resin seepage is eliminated and the timber is a uniform colour all the way through, offering an attractive finish. Since the resins and sugars are removed through the thermal-modification process, the timber will not secrete resin, even in high temperatures, making the material suitable for use in hot tubs and saunas.

This is because, to make a sauna or hot tub long-lasting, the material must have high moisture resistance and be less prone to decay. These properties are carried throughout our ThermoWood timbers.

In saunas, unmodified wood heats up much more harshly than ThermoWoods, so often, sitting or lying on them can feel uncomfortable, even after covering the wood with a sheet or towel. ThermoWood heats up much less, even when heat is set to the maximum limit, this material emits a comfortable temperature for humans and eliminates the risk of burning. Increasing safety of staying in the sauna.

Image: HUUM Sauna

There is a wide range of benefits that using ThermoWoods for saunas and hot tubs carry:

  • The thermal modification process is eco-friendly and does not emit harmful substances into the atmosphere such as harmful chemicals used to preserve unmodified timbers.

  • ThermoWood timber has high wear resistance and durability.

  • ThermoWoods are more resistant to rot and mould compared to untreated wood.

  • Saunas using ThermoWood timber will become less deformed over time compared to unmodified timber in extreme temperatures due to its stability.

  • ThermoWoods have high thermal insulation properties.

  • Various colours and shades are available.

  • The timber is safe to use.

The only disadvantage of using ThermoWood timber for saunas and hot tubs is that the material costs more than unmodified timber, this is due to the technological expertise implemented to achieve the strong, durable properties mentioned above. We believe the cost is entirely justified!

Browse our range of ThermoWoods here and start building your dream sauna or hot tub today!

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