All the natural wood boards we have selected for the GRAD system have distinct advantages over traditional softwood or the tropical timber alternatives. The different treatment processes involved are all sustainable and environmentally friendly – and they create finished boards that have exceptional levels of dimensional stability, are easy to clean and maintain, have improved compression strength, and are extremely resistant to rot or decay – some with ‘rot free’ warranties of over 50 years.
Thermo Treated Softwoods
First developed in the 1930’s, the thermal modification of timber is now a computer controlled kiln based process that preserves wood in its most natural and flawless state, using just heat and water – no nasty chemicals at all. Our raw softwood (all from managed forests) is dry heated to around 130c to remove all the moisture, then steam heated to over 200c and held at that temperature for several hours. Finally, it is water spray cooled to ensure a final moisture content of just 5%. All this careful and precise attention triggers three important changes in the resulting timber: Firstly, caramelisation of Lignin in the wood causes colour change throughout each plank, creating the rich browns of more tropical timber to appear. Secondly, the actual cellular structure of the wood is physically altered to significantly reduce all moisture induced movement. Finally, the rot resistance of the timber is dramatically improved, because the sugar content burns away – this eliminates the food source for all the mould, fungus or biological decay which would normally cause deterioration. Our thermo-treated timbers are much lighter to handle than hardwoods, much less destructive to any tools required during the installation, they create non-toxic sawdust, and they have a low thermal conductivity – so no hot deck boards. After exposure to moisture and sunlight (and without any UV protectant oil) thermo-treated timbers will naturally weather down to a soft platinum-grey colour. For further technical information visit http://www.thermotreatedwood.com/what.html
Developed in Norway (and researched for over a decade before launch) kebonisation is an environmentally friendly process which enhances the properties of softwood by injecting it with a water based, toxin free formula which includes Furfuryl Alcohol, a waste by-product of sugar cane. The wood is subjected to both vacuum and pressure to ensure complete absorption of the treatment solutions and then dried, before being cured at temperatures between 70-120 degrees C. The resulting timber is sustainable, durable and requires no maintenance beyond normal cleaning. Kebony’s environmental credentials have been endorsed with the receipt of the Nordic region’s ecolabel, the Swan. It’s also received Norway’s national environmental prize, the ‘Glass Bear’. The process permanently modifies the wood cell walls giving Kebony premium hardwood characteristics and a rich brown colour. Our Kebony boards are made from knot free Clear Grade New Zealand Radiata Pine. Left to weather in the Sun (without UV protectant oils) Kebony eventually develops a natural silver-grey patina. For further technical information visit www.kebony.com
Accoya Treated Timber
Using knot free, sustainably-sourced Radiata Pine, Accoya is created by a non-toxic acetylation process that permanently modifies the wood to its core. The result is an environmentally friendly light toned wood with the durability and dimensional stability that matches or exceeds the performance of nature’s most durable hardwoods – such as Oak, Teak, Iroko and Sapele. Accoya wood is sourced from sustainable FSC accredited forests in New Zealand and has class-leading environmental credentials. The process creates timber with unparalleled levels of rot resistance and durability and comes with performance warranties of up to 60 years. Every batch of Accoya wood is tested after production to ensure that this durability can be guaranteed. For further technical information visit https://www.accoya.com/