The Potential Contribution of Wood in Green Building Certifications

Abstract

The building sector has a significant impact on the environment, accounting for 36% of CO2 emissions and about half of material consumption in Europe. Residential buildings dominate the European building stock. In Finland, residential buildings account for up to 80% of the existing buildings and the rate of construction is higher compared to other building types. Therefore, residential buildings play an important role in the transition to a sustainable built environment. A number of studies show that increasing the use of wood can lower the life cycle environmental impacts of buildings. In Scandinavia, the use of wood in small houses is well established, used in 90% of cases. Furthermore, the increasing number of high-rise wooden buildings suggests a growing interest in the potential of wood in large-scale buildings. Green building certification provides criteria to assess the sustainability level of buildings and is expected to influence the building sector in the near future, by promoting the use of sustainable technologies. The aim of this study was to investigate how green building certification schemes assess wood materials and how wood materials can help fulfil sustainability criteria for green buildings. We analyse the sustainability criteria adopted by the most common certification schemes in Finland, BREEAM, LEED and the Nordic Swan Ecolabel, as well as the upcoming Level(s) certification promoted by the European Commission. The analysis shows that the contribution of wood materials to the overall score of green building certifications accounts for between 10 and 36%. Wood is advantageous as a renewable and low-carbon material. Furthermore, wood can offer indirect benefits due to its recycling potential and to water saving in the construction stage. However, wood materials have to comply with some requirements, such as sustainable forest management and low volatile organic compound content. The new European certification suggests a comprehensive assessment including circular material life cycles.