Australian Life Cycle Assessment Society conference
The use of timber construction products and their environmental impacts is growing in Europe. This paper examines the LCA approach adopted in the European CEN/TC350 standards, which are expected to improve the comparability and availability of Environmental Product Declarations (EPDs). The embodied energy and carbon (EE and EC) of timber products is discussed quantitatively, with a case study of the Forte building illustrating the significance of End-of-Life (EoL) impacts. The relative importance of timber in the context of all construction materials is analysed using a new LCA tool, Butterfly. The tool calculates EE and EC at each life cycle stage, and results show that timber products are likely to account for the bulk of the EoL impacts for a typical UK domestic building.
This study provides a comparative life cycle assessment (LCA) of a 4060 m2, 4-storey cross laminated timber (CLT) apartment building located in Quebec City, Canada and an equivalently designed building consisting of reinforced concrete slabs and columns with light gauge steel studded walls (CSSW)...
The environmental footprint of CLT is frequently discussed as potentially beneficial when compared to functionally equivalent non-wood alternatives, particularly concrete systems. In this Chapter, the role of CLT in sustainable design is addressed. The embodied environmental impacts of CLT in a mid-rise building are discussed, with preliminary results from a comprehensive life cycle assessment (LCA) study. We also discuss other aspects of CLT's environmental profile, including impact on the forest resource and impact on indoor air quality from CLT emissions. The ability of the North American forest to sustainably support a CLT industry is an important consideration and is assessed from several angles, including a companion discussion regarding efficient use of material. Market projections and forest growth-removal are applied to reach a clear conclusion that CLT will not create a challenge to the sustainable forest practices currently in place in North America and safeguarded through legislation and/or third party certification programs. To assess potential impact on indoor air quality, CLT products with different thicknesses and glue lines were tested for their volative organic compounds (VOCs) including formaldehyde and acetaldehyde emissions. CLT was found to be in compliance with European labeling programs as well as the most stringent CARB limits for formaldehyde emissions. Testing was done on Canadian species, as there was no U.S. supplier of CLT at the time of this writing; because VOC emissions are affected by species, this work should be repeated from products made from different species.