Between full LCA and energy certification methodology—a comparison of six methodological variants of buildings environmental assessment

Abstract

Purpose Construction, as a sector of the economy, is a significant source of negative environmental impacts. The development of sustainable construction and associated initiatives are meant to reduce that impact. Buildings, for many reasons, are the complex objects of life cycle assessment (LCA) studies, which in this case can be particularly time-, data-and costconsuming. Therefore, an attempt was made to explore the possibility of finding a methodological compromise between a full LCA and the compulsory energy certification. Six methodological variants, so called compromise solutions (CS) were identified and assessed. This article presents the results of the research project financed by the Polish Ministry of Science and Higher Education (N N309 078138) and coordinated by the Wood Technology Institute in Poznan. Methods The proposed CS were hybrids utilising, to various degrees, the environmental life cycle assessment (LCA) and energy certification. Life cycle impact assessments were carried out using IMPACT 2002+. Results and discussion The achieved results showed that the simplifications included in the energy certification lead to a significant drop in environmental impacts (by 77.9 % on average) in relation to the impact calculated for the full LCA. The results closest to the full LCA were achieved by the compromise solution no. 4 (CS4), where simplification included the exclusion from the life cycle of: transport processes, construction site, demolition, final disposal of waste, and the majority of elements associated with the use of the building. CS4 analysed all inventory inputs which were assessed with regard to the entire environmental profile. The following truncation levels were achieved for CS4-10.7 % (conventional masonry building), 9.9 % (passive masonry building), 8.3 % (conventional wooden building) and 7.4 % (passive wooden building), indicating that 90 % of the impact calculated for the full LCA was retained. Conclusions CS4 seems to be a rational compromise between the simplicity of the methodology and the environmental significance. With the exception of the energy usage for heating, hot water and ventilation, CS4 also proposes including, in the analysis, the production of building material and additional elements associated with the use stage, e.g. energy usage for home appliances and lighting, land occupation, water use and wastewater treatment. However, if we were to find a rational minimum, which is close to the energy certification, then a good improvement of this methodology would be to include energy usage for home appliances and lighting as well as introducing conversion indicators, based not only on the depletion of energy resources, but also factoring in global warming and respiratory effects/inorganic compounds. Moreover, it seems that the LCA methodology and, specifically, characterisation factors, are refined to such a degree and scientifically proved that it would be possible to use the knowledge with regard to LCA to establish such indicators for energy certification.

Life cycle assessment of energy generation in Poland

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A comparative cradle-to-gate life cycle assessment of three concrete mix designs

“…Sustainability is becoming more commonly controlled in construction by regulations to prevent the risk of not having a competitive advantage over traditional o ptions (Lewandowska et al 2015); however, regulations occasionally constrain sustainability; this is because some standards limit the use of alternative materials for various concrete constituents. This gives producers little scope for sustainability and deters them from exploring other potential options.…”

Assessment of Environmental Impacts of Limestone Quarrying Operations in Thailand

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