Modified wood – heat treatment

Heat treated wood is a different approach to enhancing the durability of softwoods, and is ideal for decking, garden furniture and external cladding.

The process involves steam heating softwood to very high temperatures in a kiln. The heat goes to the core of the wood, driving out moisture and resin.

Heat treated wood can be 50% more stable than untreated softwood, is easy to work with and lightweight.

Examples include Stora Enso’s and Finnforest’s Thermowood®. For more information visit www.finnforest.co.uk or www.storaenso.com

Modified wood - acetylation

Another new way of achieving enhanced durability is acetylation, a process which uses naturally occurring acetic acid to modify the molecular structure of the wood.

The process is effective throughout the section of treated timber and provides durability (it can achieve Class 1 durability) and enhanced stability, along with an unchanged visual appearance.

Known as AccoyaTM, and available in the UK solely through BSW, it is particularly suitable for exterior joinery products – windows, doors, conservatories and cladding. It has a life of at least 50 years in such exterior joinery applications. Furthermore, its stability and compatibility with coatings allow a service life of up to 12 years before any brush applied maintenance is required. These guaranteed periods are impressive levels of performance for not just wood, but any building product.

For more information visit www.bsw.co.uk

Osmose have developed a product called Indurite, which uses a water-based impregnation system and a modified natural polysaccharide, similar to wood’s own cellulose, to endow softwoods with the hardness and strength of hardwoods. Indurite is mainly suitable for indoor products like flooring, furniture, doors and windows.

For more information visit www.protimsolignum.com/osmose/indurite.htm