Frequently asked questions Archive - Thermory

Frequently asked questions

  • Thermally modified wood
  • Cladding
  • Decking

How to take care of thermally modified wood decking?

Terraces with thermally modified wood must be cleaned thoroughly at least once a year. It’s important that you keep the surface free of leaves, needles and other moisture-retaining debris that can promote mold.

How to take care of thermally modified wood cladding?

Thermory’s cladding and decking materials are low maintenance, especially when you choose to let the wood turn naturally gray. If you wish to keep the original thermally modified wood colors, treat the wood with penetrating oil with colourtone.

Why does thermally modified wood turn gray over time?

If wood is exposed to ultraviolet light it begins to break down the wood’s natural color and the wood begins to fade and then grey. This is common for all types of wood. Thermally modified wood seems to grey more quickly due to the process of extracting the wood’s natural tannins during the thermal modification process.

Will thermally modified wood fade or can i keep the colour?

Yes, it will fade if left untreated – as all wood products do – but this will not impact rot resistance or stability.

Treat with penetrating oil (not a sealer) with colourtone to reflect the UV rays of the sun to allow the wood color to last longer or allow to age naturally to a beautiful silver-gray.

The aging process typically happens within 6 months. Keep in mind that wood is a natural material and so any color changes may be uneven. Each board ages in its own way and different sides of the building’s facade will also age differently depending on the sun and rain they’re exposed to.

Why prefer painted thermowood to regular painted wood cladding?

Choosing thermally modified wood for your painted cladding is a more durable and low-maintenance option. Unlike chemical impregnation, thermal modification enhances the wood throughout, not just the outer surface. The result is boards that are stable and durable in the long run.

Is thermally modified wood fire resistant?

Thermory’s wood products’ fire classes are indicated on declarations of performance.

Higher fire resistance classes can be achieved with special treatments. Contact us for more information as requirements may differ for each country. 

How is thermally modified wood different from kiln dried wood?

Kiln dried wood is not thermally modified wood. It is simply dried in a kiln to a certain moisture content to help it perform better for its final usage. Kiln drying doesn’t change the cellular structure of the wood as does thermal modification, just the moisture content.

Thermal modification is a scientific process that changes the characteristics, chemistry, structure and performance of wood at the cellular level. Thermally modified woods are super-heated, at much higher temperatures than kiln-dried woods, in a highly controlled manner.

What is thermal modification?

Thermal modification is a non-toxic treatment process that is used to improve wood’s material properties, including its dimensional stability and biological resistance. Only heat and steam are used for this process, no chemicals.

Thermal modification is a scientific process that changes the characteristics, chemistry, structure and performance of wood at the cellular level.