• Energy Research

The construction industry adds a high share to global CO2 emissions and, thus, to the global climate crisis. Future buildings need to be planned, constructed, operated, and deconstructed in a lifecycle-oriented manner so that the building stock represents a capital asset for future generations. The greatest leverages for reducing a building’s CO2 emissions lie in the early project phase and subsequently in the tendering and awarding process, which makes early Life Cycle Assessment (LCA) indispensable. In this study, we set a sociological research framework consisting of (i) choosing a research topic, (ii) conducting a literature review, (iii) measuring variables and gathering data, (iv) analyzing data, and (v) drawing a conclusion. Since there are countless studies that apply LCA in the construction sector for environmental assessment, emission reduction, or decision support, we posed the question of whether LCA was also applied in the public building tendering and awarding process. Furthermore, we focused on identifying obstacles to LCA implementation in this early project phase. Therefore, we applied the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and conducted a Systematic Literature Review (SLR). The results show that numerous articles focused on sustainable tendering or green public procurement in the construction industry; however, the LCA method is scarcely used in the procurement processes (19 articles in the final sample). Based on our findings, the main obstacles to LCA implementation in the procurement process are highlighted in the study. In the future, the mandatory integration of LCA into the procurement process will be crucial to reduce the CO2 emissions generated by the construction industry and thus contribute to the EU climate target plan to ensure carbon neutrality by 2050.

Abstract The building sector is responsible for 39% of greenhouse gas (GHG) emissions; thus, it has a significant amount of potential to reduce the effects of climate change. Several active- and passive solutions and strategies have been developed and proposed in the literature. Among them, wood is highlighted as a promising solution to minimize GHG from buildings. However, the benefits, especially in the circular economy, are not fully evaluated due to methodological choices. Motivated by this knowledge gap, this article aims to evaluate the benefits of wood reuse compared to traditional building construction solutions. For this purpose, we have calculated the environmental impacts of a building situated in Graz, Austria. Four different scenarios are considered. The first scenario is a fully reinforced concrete building. The second scenario is a structural beam-column made from reinforced concrete with walls made of concrete blocks. The third scenario is a beam-column made from reinforced concrete with external walls based on clay blocks. Finally, the last scenario is a full wooden building. Following the standardized life cycle assessment (LCA) method, global warming potential (GWP) is calculated through a 0/0 approach. These evaluations were made possible by correlating the impacts released from producing wooden elements and the uptake of biogenic carbon from the forest. Without considering the possibility of material reuse, the wooden structure has a 5 % lower GWP value than the reinforced concrete building. Comparatively, the other building scenarios have almost similar impacts as the building in reinforced concrete. In the case of material reuse, the wooden structure building shows potential to develop projects with 44% lower environmental impacts.

Air pollution is a global concern, especially in cities and urban areas, and has many implications for human health and for the environment. In common with other industrial sectors, the construction industry emits air pollutants. In scientific literature, the contribution the construction industry makes to air pollution is underexposed. This systematic literature review (SLR) paper gives an overview of the current literature regarding air pollution within the construction industry. Air pollution is discussed focusing mainly on three levels: (i) buildings and their building life cycle stages, (ii) construction processes and components, and (iii) building material and interior. The final sample of the SLR comprises 161 scientific articles addressing different aspects of the construction industry. The results show that most articles address the use stage of a building. Particulate matter in different sizes is the most frequently examined air pollutant within the SLR. Moreover, about a third of the articles refer to indoor air pollution, which shows the relevance of the topic. The construction industry can help to develop a healthier built environment and support the achievement of cleaner air within various life cycle stages, e.g., with optimized construction processes and healthier materials. International agreements and policies such as the Sustainable Development Goals (SDGs) can support the sustainable development of the construction industry.

Abstract Purpose The greenhouse gas (GHG) emissions caused by the construction industry account for an enormous share of total global CO2 emissions. The numerous construction activities therefore continue to reduce the remaining carbon budget. One lever for the reduction of these GHG emissions lies in the procurement process of buildings. For this reason, a process model was developed that takes embodied and operational emissions into account in the tendering and awarding phase of buildings. Methods To validate the developed theoretical framework, environmental life cycle costing (eLCC) was conducted on a single-family house case study, taking into account external cost caused by GHG emissions. Various shadow prices were defined for the calculation of external cost to identify changes in award decisions. We further investigated a results-based climate finance (RBCF) instrument, i.e., the GHG emission bonus/malus, to demonstrate an approach for calculating Paris-compatible cost (PCC) scenarios. Results We show that an award decision based on life cycle costing (LCC) leads to a 12% reduction in GHG emissions. A further reduction in GHG emissions can be achieved by awarding contracts based on eLCC. However, the required shadow prices within the eLCC awards to influence the award decision are quite high. With the development of the LCA-based bonus/malus system, PCC scenarios can be determined at sufficient shadow prices, and further GHG emission reductions can be achieved. Conclusions Since the implementation of LCA and LCC in the tendering and awarding process is currently not mandatory, in this context, the next step towards Paris-compatible buildings must first be taken by the awarding authorities as well as the policy-makers. However, the application of the LCA-based bonus/malus system and thus the awarding of contracts according to PCC scenarios show the enormous GHG emissions reduction potential and thus represent an innovative and sustainable framework for an adapted procurement process.

Over the past decades, it has become apparent that increasing demands in the construction industry have repeatedly led to project delays and increased project costs in practice. These demands have increased as a result of international and national action plans that have been developed to achieve the climate target paths and, therefore, the necessary reduction of CO2 emissions in the construction industry. We address this problem by developing a sustainable construction maturity model (SCOMM) to answer the following research question: “What is a holistic quality assurance tool for the early design phase of buildings to monitor (sustainable) planning practices in order to achieve better certification results?”. The model includes a self-assessment procedure for the building design process, based on Software Process Improvement and Capability dEtermination (SPiCE) and the German Sustainable Building Council (DGNB) building certification system. The results show that systemic interactions between sustainability criteria can be identified in the early design phase, allowing the quality of planning practices to be evaluated and early project management to be implemented to achieve the best certification results. Our findings will enable clients and users of the construction industry to better manage the complexity of the sustainable design process and avoid undesirable developments in building projects.

As part of the European Green Deal, the European Commission recently launched the project “New European Bauhaus of the 21st Century” to promote climate-neutral, affordable, and creative design approaches and transform the built environment towards sustainability. Based on a forecasting and backcasting approach, we developed three sets of measures containing eighteen individual measures, with the overall aim of reducing the consumption of mineral raw materials in line with the sustainability strategies (consistency, efficiency, and sufficiency) from exploration through material processing, to semi-finished product production. The developed measures address in detail the reduction of primary raw material consumption, the increased use of secondary raw materials, and the intensification of access to important domestic raw material sources, as well as the efficiency and productivity progression of the Austrian raw material industry. The implementation of the measures will raise the transparency and traceability of raw material routes, material flows, and supply chains through improved and comprehensive data collection and processing. The developed measures were handed over to the Austrian Federal Government in February 2022 to push the achievement of Sustainable Development Goal (SDG) 12 in Austria.