Towards indicative baseline and decarbonization pathways for embodied life cycle GHG emissions of buildings across Europe

Abstract Buildings’ construction and operation are major contributors to global greenhouse gas (GHG) emissions, and the substantial reduction of GHG emissions across their full life cycle is required to enable meeting international climate targets. For effective climate change mitigation - as recent studies have shown - a special focus has to be put on lowering embodied GHG emissions, i.e., emissions related to construction production manufacturing and construction processes, maintenance and replacement as well as end-of-life processing. As the importance of reducing embodied GHG emissions rises, so does the need for understanding both the baseline and pathways for reduction across the full life cycle of buildings. In this paper, we offer insights into the data-driven analysis of embodied GHG emissions across the whole life cycle of buildings from recent studies. Our investigation builds on the data collection, processing and harmonisation of around 1.000 building LCA case studies. We offer an integrated perspective on GHG emissions across the life cycle of buildings, considering historical trends, current baselines and indicative reduction pathways for embodied GHG emissions in different countries across Europe. This serves to inform our current ‘decade of action’ and the transformation to a regenerative built environment by 2050.</jats:p

Implications of using systematic decomposition structures to organize building LCA information: A comparative analysis of national standards and guidelines- IEA EBC ANNEX 72

The application of the Life Cycle Assessment (LCA) technique to a building requires the collection and organization of a large amount of data over its life cycle. The systematic decomposition method can be used to classify building components, elements and materials, overcome specific difficulties that are encountered when attempting to complete the life cycle inventory and increase the reliability and transparency of results. In this paper, which was developed in the context of the research project IEA EBC Annex 72, we demonstrate the implications of taking such approach and describe the results of a comparison among different national standards/guidelines that are used to conduct LCA for building decomposition. Methods: We initially identified the main characteristics of the standards/guidelines used by Annex participant countries. The "be2226" reference office building was used as a reference to apply the different national standards/guidelines related to building decomposition. It served as a basis of comparison, allowing us to identify the implications of using different systems/standards in the LCA practice, in terms of how these differences affect the LCI structures, LCA databases and the methods used to communicate results. We also analyzed the implications of integrating these standards/guidelines into Building Information Modelling (BIM) to support LCA. Results: Twelve national classification systems/standards/guidelines for the building decomposition were compared. Differences were identified among the levels of decomposition and grouping principles, as well as the consequences of these differences that were related to the LCI organization. In addition, differences were observed among the LCA databases and the structures of the results. Conclusions: The findings of this study summarize and provide an overview of the most relevant aspects of using a standardized building decomposition structure to conduct LCA. Recommendations are formulated on the basis of these findings

Inventory of the existing residential building stock for the purpose of environmental benchmarking

Abstract The current renovation rate in Belgium is less than 1% and should be increased to 2, 5% to reach the European targets to reduce the GHG emissions by 2050. There is a need to rapidly increase the renovation rate and at the same time guarantee that these renovations reduce the environmental impact on our planet. In order to define environmental benchmarks for existing buildings and their renovation targets, a better understanding of the existing building stock is needed. In this paper, the approach used to model the existing building stock is presented for the specific case of Leuven. The methodological steps, challenges and data gaps are presented in detail. The proposed building stock model uses GIS data in order to gain insights in the geospatial distribution of the impacts of the stock. These spatial maps moreover allow to clearly visualise the impacts which can improve communication and contribute to policy actions.</jats:p

Turning the existing building stock into a resource mine: proposal for a new method to develop building stock models

Abstract The construction sector is facing an important challenge to reduce its resource consumption. A promising strategy is to reduce the need of virgin resources by using the existing building stock as a resource mine. Various insights are needed to enable this. It should be clear how many materials are in the stock, when these will become available and to what extent these can be reclaimed in an environmentally and economically viable way. For this purpose a spatio-temporal building stock model is being developed and tested on the city of Leuven, Belgium. In a next step it will be assessed how these flows can be reclaimed in an environmentally and economically viable way. This paper provides a review on the methods used for building stock modelling and proposes improvements on the bottom-up archetypes scaling method. Building parameters relevant to material reuse and are introduced and a new methodology for upscaling is presented, using two data analysis techniques: a clustering algorithm and an artificial neural network.</jats:p

Architecture and Sustainability: Critical Perspectives for Integrated Design

info:eu-repo/semantics/publishe

Integrating climate change in life cycle assessment of buildings: literature review

Abstract The operational energy use and related greenhouse gas emissions of buildings are typically influenced by changes during the building service life such as climate change, technological evolution and energy mix evolution. Only few LCA studies consider these temporal variations. This paper investigates how climate change is currently considered in LCA studies. Three aspects related to the influence of climate change on the life cycle impact of buildings are focused on: (1) changes in operational energy use (heating and cooling) due to changes in the climatic context of the building, (2) changes in operational energy use due to technological evolution or climate regulations and (3) changes in energy mix due to climate regulations. All three influence the energy use and related environmental impact but the extent of the effect depends on the considered region, time step and environmental indicators. It is hence recommended to choose an appropriate time period when considering climate change in LCA and consider variations within a time period via dynamic building simulations or to include a static correction. A holistic set of impact categories should be focussed on to avoid burden shifting and the most influencing parameters should be checked via a sensitivity analysis.</jats:p