New treatment could eliminate demand for tropical hardwoods

An alternative to tropical hardwoods, which are often unsustainably harvested and increasingly endangered, comes from Kebony, a Norwegian company that has developed a process for treating woods such as pine, ash, and maple to make them suitable for exterior uses in a more sustainable manner.

The process of kebonization is similar to pressure treating wood (which is another way to make soft woods usable for exterior use). But, instead of soaking the wood in toxic chemicals like chromated copper asrsenate (CCA, which is now banned for most uses in the US and the EU) or alkaline copper quaternary compounds (ACQ, the most widely used replacement for CCA after the ban), it is instead soaked in furfuryl alcohol, a waste byproduct from sugar cane which is also sometimes used as a food additive. There are no special handling requirements or precautions needed to deal with waste from this wood, and it can be disposed of just like any other untreated wood.

During the kebonization process, the alcohol becomes a resin that reinforces the cells of the wood. The result is a wood with excellent outdoor exposure tolerance like teak or mahogany, but with a harder surface than many of the tropical woods that it replaces. The wood also naturally fades to a silvery-grey color much like those tropical woods, as well.

The wood that is used in this process can be any of a number of non-tropical species that are already being produced in more sustainable manner. (Whether FSC certified or merely conventionally farmed, the wood does not need to be harvested out of rainforests.)

Kebony wood can also be used for building siding, and it is so water and weather resistant that it has even been used for building roofs and for boat decking. The process also makes the wood less prone to swelling due to moisture. There is no necessity to paint Kebony wood, and it can withstand decades of exposure to the weather before any maintenance is necessary.

via: The Economist and thanks, Kat