Novawood Thermo Ash

Thermal modification enhances the natural characteristics of American ash to create a product which is extremely durable and stable with an attractive appearance. 

The kiln dried timber is heated to 212°C at which point the timber’s natural properties change and it turns a rich walnut brown colour. 

The process uses only heat and water and is completely chemical free with the energy for the kilns generated from wood waste. 

All the timber used to produce Thermo Ash is FSC certified, achieving the highest environmental standard.

Technical Information

Durability – Class 1 – Suitable for Exterior use, in ground contact without protection (in accordance with En prCENT/TS 15679) 

Stability – As a result of the Thermowood process the stability is vastly improved in comparison to un-modified wood.



Thermo Ash is available in two grades: FAS and Extra. 

FAS – graded in accordance with the NHLA grading rules 

Extra grade is 3 sides clear and is only available in a skipped / dressed finish. Extra grade is selected after the modification process to provide the highest quality product.


Machined profiles are available to order on a forward basis

Additional Services

Laminated sections available for bespoke large dimension requirements.

Surface treatments including oiling and charring are available to order.

Contact Us

If you have any questions, feel free to contact us below.

Scroll to Top