|
For Western Red Cedar products, the study was based on data obtained from a representative cross section of cedar mills in British Columbia and Washington state in 2007. Secondary publicly available data were used to develop life cycle inventories (LCIs) for clay brick, fiber cement and vinyl siding. Cradle-to-grave LCIs for wood-plastic composite decking made with either virgin or reprocessed plastic were also developed using secondary data sources as well as information collected from experts in the petrochemical and wood-plastic composite fields.
In order to evaluate the environmental impacts of the life-cycle stages of product alternatives, the life cycle was modeled as four distinct life-cycle stages: resource extraction and manufacturing, transportation to customer, installation and use, and end-of-life disposition. This approach helps identify where environmental contributions occur within the life cycle of each product system.
Summary - Decking and Cladding
The following statements summarize the LCA results of the study for decking and cladding products, giving consumers a reliable basis for comparison. Environmental impact measures applied consistently to each product were: total primary energy on a cumulative demand basis, global warming potential, acidification potential, aquatic eutrophication potential, ozone depletion, smog formation potential, and human particulate (respiratory)effects.
DECKING:
Western Red Cedar (WRC) decking substantially outperformed composite decking in each of the seven criteria tested and was by far the product with the least environmental impact when compared with both virgin and recycled wood-plastic composite decking products.
Even after subjecting the cedar decking results to a 'worst case' scenario in which WRC required the replacement of 20% of boards in normal service and periodic application of coatings, the environmental impact results remained strongly favorable to Western Red Cedar over the 'best case' scenario for composite decking.
CLADDING:
Western Red Cedar (WRC) cladding had the best overall performance when compared to vinyl, fiber-cement and brick; it received top marks in five of seven impact criteria, including "global warming potential."
Total life energy of Western Red Cedar cladding can be further improved by altering end-of-life disposal practices away from the assumed practice of 100% landfill, to a mix of reuse, energy recovery and landfilling. This practice, already reality in many communities, results in cedar siding becoming a net "carbon sink;" other products tested remained green house gas contributors.
Cedar siding impact on smog and eutrophication - the criteria in which it was not the leader - can be traced directly to the use of paint, not the natural characteristics of cedar. Use of high quality paints and stains (some of which carry length performance warranties) or the use of the new water borne coatings would have a very positive impact on results.
Western Red Cedar - The Environmental Choice
Western Red Cedar offers unique, natural performance characteristics and exceptional beauty that bring warmth, character and longevity to the interior and exterior of residential and commercial projects around the world. Whether you choose knotty or clear grades, Western Red Cedar offers virtually unlimited versatility and design flexibility in terms of size and profile.
Western Red Cedar is a truly sustainable building material. It has the lowest environmental impact when compared with other materials such as brick and fiber cement. Independenlty certified, it is harvested legally and sustainably from managed forests in British Columbia.
Go Green with Western Red Cedar
|
Print this page
