• Heat Treatment of Wood Since 1997

  • Heat Treatment of Wood Since 1997

  • Heat Treatment of Wood Since 1997

  • Heat Treatment of Wood Since 1997

  • Heat Treatment of Wood Since 1997

  • Heat Treatment of Wood Since 1997

Best of Wood

– Heat Treated Wood

Are you looking for high-quality heat treated wood for indoor or outdoor use? Finnish HJT-Holz Oy, a company specialized in the production and further processing of heat treated wood, offers a solution to meet your needs.

Extensive experience, patented production technology and the best raw material from trusted partners guarantee the quality of our products. Contact us and tell us what you need! »

Thermowood®, or heat treated wood, is suitable for many purposes. In the interior, it can be used in, e.g., walls, ceilings, floors, saunas, fittings, and furniture. On the exterior, it is suitable for use in, e.g., facades, terraces, doors, and windows.

Heat treatment improves both the qualities and the appearance of the wood. The beautiful brown color gives it a stylish, almost hardwood-like look.

HJT-Holz Oy/Thermowood -brochure.pdf

Heat Treatment of Wood

– Protection without Chemicals

Heat treating wood is a natural way of protecting it. It improves its rot, weather and thermal resistance, and reduces the movement of wood due to moisture. No chemicals are used in the treatment, since it is based on high temperature and water vapor.

During the heat treatment, the temperature of the wood is first increased to over 160 °C, and then deceased back to the normal temperature. The treatment lasts from 1.5 to 3 days, and it is regulated with the help of hot air and water vapor. The structure of the wood changes as water and extractives, such as pitch (terpenes), are removed from it.

On the Terms of Quality and the Environment

Taking quality and the environment into consideration is a matter of honor for us. It applies to all that we do. We are committed to following the principles of financially, ecologically and socially sustainable forestry. We comply with legislation and other regulatory requirements, and we also expect our contractual partners to do the same. It is of paramount importance to us that we know the origin of the lumber we acquire.

Our company has been granted the Finotrol-PEFC-COC-1505 certificate. The certificate attests that the management of the origin of the wood has been assessed and it follows the international PEFC standard PEFC ST 2002:2013. The certificate covers lumber acquisitions, sales, data systems, internal control and files. On the basis of the certificate, the Finnish Forest Certification Council has granted us the right to use the PEFC mark.


We have supplied heat treated wood for different needs and to various locations both in Finland and abroad.

Heat Treatment of Wood Since 1997

Finnish HJT-Holz Oy is a company specialized in the production and further processing of heat treated wood. We have operated in the field since 1997, and we have been a member of the Finnish Thermowood Association since 2000. We are entitled to use the association’s ThermoWood® trademark. It means that we co-operate in, for instance, quality control and research.

We have 7 heat treatment facilities for wood, 4 in Vilppula and 2 in Kolho, Finland. In addition to those, we have our own planing mill and surface treatment line. In total, our capacity is approx. 40,000 m3. Some 95% of our products are exported.


heat treatment facilities for wood

~40 000

m3 capacity

95 %

of production exported

Contact us

Johannes Salo
+358 44 3147 566
Sales (English)
Ville Salo
+358 44 2572 884
CEO (Deutsch)
Hannu Salo
mobile +358 50 5542 965
tel. +358 3 4718 138
fax +358 3 4718 137
Jarkko Salo
+358 50 5253 548

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