Gulf Construction Online - AHEC extols green credentials of wood

Green buildings

Virgin Atlantic’s Sunken Lounge at Heathrow Airport, London. BELOW: Wiles.

AHEC extols green credentials of wood

Despite not being backed by formal certification, Roderick Wiles of Ahec argues that American hardwoods are inherently sustainable and an environment-friendly alternative to many other building materials commonly used in the Gulf.

01 June 2011

THE American Hardwood Export Council (AHEC) is making all-out efforts to prove the inherent green credentials of American hardwoods, refusing to be stymied by the absence of formal certification such as the FSC (Forest Stewardship Council) stamp for sustainability that appears on many wood products nowadays.

Roderick Wiles, director for the Middle East, India and Oceania at AHEC, says he is trying very hard to prove to architects and engineers that American hardwoods are not only aesthetically pleasing but have the assured environmental and sustainability credentials that are increasingly required by developers, interior designers and even furniture retailers around the world.

The absence of the FSC endorsement is not ignorance, obduracy or oversight on the part of AHEC and its members, he points out. “Rather, it is a reflection of the unique circumstances of hardwood cultivation in the US, where there are more than 10 million individually-owned forestry plots producing hardwood, which have been managed sustainably for generations,” Wiles explains. “Indeed for the owners of many of these plots, the primary reason for engaging in forestry is not for wood production but rather the pleasure of having a beautiful natural vista, for recreation and for hunting. The fact that stock can be harvested and sold is really a bonus rather than an economic necessity – and certification is expensive and complex and many owners simply cannot justify that kind of trouble and expense.”

Emphasising that American hardwoods are inherently sustainable, Wiles also cites another instance of formal certification for proving sustainable qualities – the Leed (Leadership in Energy and Environmental Design) green building rating system where timber in general and American hardwoods, in particular, get a rap, as the systems require an FSC logo.

According to him, the current ratings systems do not give due consideration to the type of materials used. “It is ironic that even if you do use FSC-certified wood products in a building you may only get one Leed point, whereas you can get the same one point for having a bike rack outside – and that’s probably made from aluminium, which is much more energy intensive,” he says.

In addition, one of the ingrained assumptions he definitely wants to change in green building design and specification is the idea that buying locally is inherently ‘greener’ and therefore better, pointing out that transport of materials for 500 km by truck can quite possibly create a larger carbon footprint than the transport of the same materials many thousands of kilometres by sea.

Nevertheless, AHEC has a card up its sleeve when dealing with Leed and green building councils and that is life-cycle assessment (LCA) – the scientific method that has been designed to measure and evaluate the environmental burdens associated with a product or activity.

Wooden beacons ... complement the architecture.

LCA does this by systematically identifying and assessing the energy and materials used and carbon dioxide and other emissions released into the environment over the life cycle of a particular product. To that end, AHEC has commissioned probably the largest LCA study undertaken in the international hardwood sector, which is being taken up by PE International, a leading LCA consultant headquartered in Germany. This report is due out towards the end of this year but, as an interim measure, AHEC is promoting a ‘Preliminary assessment of the carbon footprint of American hardwood kiln dried lumber supplied to distributors in the UAE’, written by Rupert Oliver of Forest Industries Intelligence. The assessment itself, which is based on a number of well-founded assumptions drawn from other studies, seems to indicate that the process of growing, cutting, sawing and transporting American hardwoods to the UAE is actually carbon-negative and that hardwood from the US is an environment-friendly alternative to many other building materials commonly used in the Gulf.

The key is carbon sequestration during photosynthesis as the tree absorbs carbon dioxide (CO2) from the atmosphere and the fact that the amount of carbon stored in dried wood is approximately 50 per cent by weight. This gives a carbon dioxide equivalent value of 1.835 kg CO2e per kg of dry wood. The estimated CO2 emissions generated in cutting, hauling the trees to the saw mill in the US, mill processing and then sea and land transportation from the mill to the distributor in the UAE amounts to approximately 0.4498 kg CO2 per kg weight. Thus the carbon sequestration more than offsets the total carbon emissions resulting from harvesting, processing and transporting of American hardwoods to UAE distributors. Furthermore, says Oliver, “even if the considerable benefits of carbon sequestration in American hardwood products were not considered, emissions of 0.45 kg CO2e per kg are likely to compare favourably against other materials – including most domestic UAE wood and non-wood products and even recycled materials.”

Wiles comments: “Eventually, we should be able to produce environmental product declarations for American hardwoods. These are like nutrition labels – they tell you exactly what it contains, what its environmental footprint is and then you can compare that directly with any other material on a level playing field. And it is science based and fact.”
Some of the ratings systems are gradually starting to recognise the wider benefits of using timber, Wiles points out. “In Europe, the Germans, French and British rating systems are recognising LCA now and the Australian one will recognise LCA next year,” he says.

And not before time in Wiles’ opinion: “When you think about it, the only truly sustainable building material is timber – you can’t say the same for any other material,” he says.

The industry is also looking at widening the area of application for American hardware beyond its traditional use in flooring, cabinetry and other interior applications.

“AHEC is not really a technical organisation, but we are exploring ways of thermally modifying American hardwoods to make them applicable in cases of outdoor decking and window frames. We are also looking at structural applications – some architects have been interested in using timber in this way as opposed to steel,” Wiles says.

A number of interesting structural projects have already been undertaken, notably Portcullis House near the Houses of Parliament in London. The building has a large glass dome, which was originally due to be supported by steel struts. However, it is actually supported by American white oak, which has been found to be stronger than steel in certain applications, according to Wiles.

In the Gulf region, AHEC is confident of seeing an increase in demand for American hardwood. “The year 2009 was a difficult one for American hardwood exports to the Middle East in general and Dubai in particular. But exports to the region have rebounded, reaching a value of almost $73 million in 2010 and we look forward to further growth particularly in the key markets of Egypt and Saudi Arabia,” he concludes.