ThermoWood®: thermally modified wood

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High-quality, long-lasting and affordable

ThermoWood® is the result of an innovative process in which heat treatment plays a central role. Thermal modifications ensure that the durability of the wood increases and its quality improves.

The first thermally treated wood was produced in the 1930s by the German scientists Stamm and Hansen, and in the 1940s by the American scientist White. Bavendam, Runkel and Buro then continued the research in the 1950s. At the beginning of 1990s the term ThermoWood® was coined for the first time when the VTT (Technical Research Center in Finland) further expanded the research to heat treatment, and thus the ´ThermoWood® method´ was developed.

The ThermoWood® production process uses heat, steam and water. Wood is heated for a long period at temperatures up to 208°C. This heat treatment also produces specific chemical changes of the wood, giving rise to a long-lasting and stable product.

Applications with Thermowood®

LDCwood is a member of the International ThermoWood Association. This quality label offers the best guarantee for the quality of the various products, amongst others because they collaborate on research and quality control in order to improve the application of the products.

In principle, the ThermoWood® process can be applied to all types of wood, but in the initial phase LDCwood concentrates on ayous, fraké from Cameroon, ash and pinewood. Thanks to the process, the wood is better protected against water and decay, it is better insulated and it will shrink or expand less quickly.

Ayous is a hardwood from tropical West Africa. Depending on the origin, the colour and quality can vary, but the hardwood is always whitish to creamy yellow.

Fraké is also a type of hardwood from West Africa. The colour ranges from light yellow or yellow grey to dark brown, and sometimes even greenish. Locally discoloration can also arise in the form of brownish flames.

Pine is a type of wood from Europe or Northern Asia. This softwood displays a white to pale yellow-brownish colour, which after long-term exposure to light and air turns to yellow brown.


ThermoWood® has many benefits. It’s for example cheap, tough and good for the environment. Discover all the unique characteristics of our ThermoWood® here.

Durability ThermoWood ® lasts longer
Biological durability The thermal modification has an effect on the durability of the wood.
Resistant to all types of insects
Thermal properties The thermal conduction is 20-25% lower
100% natural Free of resin and chemicals
Emissions Volatile organic substances by 55-82%
Hardness The higher the temperature, the higher the hardness value
Moisture content The moisture content can be 40-50% lower 

Thermal modification

Technical details

Wood is already very long-lasting, and its thermal treatment ensures an even higher stability and durability.

Wood is composed of 50% cellulose, 23% hemicellulose, 20% lignin and 7% other organic substances, named extraction residues. The thermal treatment removes resin, other extracts and their attached OH or Hydroxyl groups from the wood.

This treatment process reduces the water absorption of wood and counters expansion and shrinkage, and simultaneously increases the resistance to decay. Another factor that contributes to the durability of the wood is the crystallisation of the cellulose. The change into hemicellulose increases the durability. Hemicellulose breaks down into furfural and carboxylic acid. The caramelisation of lignin, which is caused by the heat, gives the wood a darker colour.