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(PE)-UHPFRC, a novel strain hardening ultra high-performance fiber reinforced concrete (UHPFRC) with low clinker content, using Ultra-High Molecular Weight Polyethylene (UHMW-PE) fibers, was developed for structural applications of rehabilitation. A comprehensive life cycle assessment (LCA) was carried out to study the environmental impact of interventions on an existing bridge using PE-UHPFRC compared with conventional UHPFRC and post-tensioned reinforced concrete methods in three categories of global warming potential (GWP), cumulative energy demand (CED), and ecological scarcity (UBP). The results showed 55% and 29% decreases in the environmental impact of the PE-UHPFRC compared with reinforced concrete and conventional UHPFRC methods, respectively, which highlighted the effectiveness of this material for the rehabilitation/strengthening of structures from the viewpoint of environmental impact.

This research explores the carbon removal of a novel bio-insulation composite, here called MycoBamboo, based on the combination of bamboo particles and mycelium as binder. First, an attributional life cycle assessment (LCA) was performed to define the carbon footprint of a European bamboo plantation and a bio-insulation composite, as well as its ability to remove CO2 along its lifecycle at a laboratory scale. Secondly, the Global Worming Potential (GWP) was estimated through a dynamic LCA with selected end-of-life and technical replacement scenarios. Finally, a building wall application was analyzed to measure the carbon saving potential of the MycoBamboo when compared with alternative insulation materials applied as an exterior thermal insulation composite system. The results demonstrate that despite the negative GWP values of the biogenic CO2, the final Net-GWP was positive. The technical replacement scenarios had an influence on the final Net-GWP values, and a longer storage period is preferred to more frequent insulation substitution. The type of energy source and the deactivation phase play important roles in the mitigation of climate change. Therefore, to make the MycoBamboo competitive as an insulation system at the industrial scale, it is fundamental to identify alternative low-energy deactivation modes and shift all energy-intensity activities during the production phase to renewable energy.

The building sector has a significant potential to reduce the material resource demand needed for construction and therefore, greenhouse gas (GHG) emissions. Digitalization can help to make use of this potential and improve sustainability throughout the entire building’s life cycle. One way to address this potential is through the integration of Life Cycle Assessment (LCA) into the building process by employing Building Information Modeling (BIM). BIM can reduce the effort needed to carry out an LCA, and therefore, facilitate the integration into the building process. A review of current industry practice and scientific literature shows that companies are lacking the incentive to apply LCA. If applied, there are two main approaches. Either the LCA is performed in a simplified way at the beginning of the building process using imprecise techniques, or it is done at the very end when all the needed information is available, but it is too late for decision-making. One reason for this is the lack of methods, workflows and tools to implement BIM-LCA integration over the whole building development. Therefore, the main objective of this study is to develop an integrated BIM-LCA method for the entire building process by relating it to an established workflow. To avoid an additional effort for practitioners, an existing structure for cost estimation in the Swiss context is used. The established method is implemented in a tool and used in a case study in Switzerland to test the approach. The results of this study show that LCA can be performed continuously in each building phase over the entire building process using existing Building Information Modeling (BIM) techniques for cost estimation. The main benefit of this approach is that it simplifies the application of LCA in the building process and therefore gives incentives for companies to apply it. Moreover, the re-work caused by the need for re-entering data and the usage of many different software tools that characterize most of the current LCA practices is minimized. Furthermore, decision-making, both at the element and building levels, is supported.

The global shift towards embodied carbon reduction in the building sector has indicated the need for a detailed analysis of environmental impacts across the whole lifecycle of buildings. The environmental impact of heating, ventilation, and air conditioning (HVAC) systems has rarely been studied in detail. Most of the published studies are based on assumptions and rule of thumb techniques. In this study, the requirements and methods to perform a detailed life cycle assessment (LCA) for HVAC systems based on building information modelling (BIM) are assessed and framed for the first time. The approach of linking external product data information to objects using visual programming language (VPL) is tested, and its benefits over the existing workflows are presented. The detailed BIM model of a newly built office building in Switzerland is used as a case study. In addition, detailed project documentation is used to ensure the plausibility of the calculated impact. The LCA results show that the embodied impact of the HVAC systems is three times higher than the targets provided by the Swiss Energy Efficiency Path (SIA 2040). Furthermore, it is shown that the embodied impact of HVAC systems lies in the range of 15–36% of the total embodied impact of office buildings. Nevertheless, further research and similar case studies are needed to provide a robust picture of the embodied environmental impact of HVAC systems. The results could contribute to setting stricter targets in line with the vision of decarbonization of the building sector.

Low temperatures and high humidity often occur in the northern basins and mountainous regions of China. This research reveals a common winter indoor environment in this rural areas characterized by low-temperature and high-humidity indoor thermal conditions. Improving this environment directly with equipment would inevitably result in significant energy consumption. Therefore, comprehending the thermal performance mechanisms of different structural building materials is of vital importance as it provides crucial baseline values for environmental improvement. This study conducted a survey utilizing user questionnaires, resulting in the collection of 214 valid responses. Additionally, a local experiment regarding thermal comfort was conducted. Simultaneously, this study monitored the indoor physical environments of these houses (a sample of 10 rooms was taken from earth houses and 12 rooms from brick houses). Parameters measured on site included air temperature, relative humidity, light illumination, and CO2. The results showed that the humidity inside the earth houses is more stable and regression models can be developed between thermal sensations and temperature for long-term residents. The residents of these earth houses are more sensitive to temperature step. In contrast, the residents of brick houses, experiencing greater environmental variability, demonstrated lower sensitivity and greater adaptability to temperature changes. In addition, heating from bottom to top is more comfortable and healthier for the residents of brick houses in Gansu. Moreover, it is more favorable for the inhabitants’ livelihood to regulate the temperature steps to a maximum of 4 °C. This study provides valuable reference information for the future design of houses in low-temperature and high-humidity environments.

Building demolition is one of the main sources of waste generation in urban areas and is a growing problem for cities due to the generated environmental impacts. To promote high levels of circular economy, it is necessary to better understand the waste-flow composition; nevertheless, material flow studies typically focus on low levels of detail. This article presents a model based on a bottom-up macro-component approach, which allows the multiscale characterization of construction materials and the estimation of demolition waste flows, a model that we call the BTP-flux model. Data mining, analytical techniques, and geographic information system (GIS) tools were used to assess different datasets available at the national level and develop a common database for French buildings: BDNB. Generic information for buildings in the BDNB is then enriched by coupling every building with a catalog of macro-components (TyPy), thus allowing the building’s physical description. Subsequently, stock and demolition flows are calculated by aggregation and classified into 32 waste categories. The BTP-flux model was applied in Île-de-France in a sample of 101,320 buildings for residential and non-residential uses, representative of the assessed population (1,968,242 buildings). In the case of Île-de-France, the building stock and the total demolition flows were estimated at 1382 Mt and 4065 kt, respectively. For its inter-regional areas—departments—, stock and demolition waste can vary between 85 and 138 tons/cap and 0.263 and 0.486 tons/cap/year, respectively. The mean of the total demolition wastes was estimated at 0.33 tons/cap/year for the region. Results could encourage scientists, planners, and stakeholders to develop pathways towards a circular economy in the construction sector by implementing strategies for better management of waste recovery and reintegrating in economic circuits, while preserving a maximum of their added value.

Climate policies such as sectoral carbon budgets use national greenhouse gas emissions inventories to track the decarbonization of sectors. While they provide an important compass to guide climate action, the accounting framework in which they are embedded lacks flexibility for activities that are international and at the crossroads of different sectors. The building activities, being largely linked with important upstream emitters such as energy production or industrial activities, which can take place outside of national borders, are such an example. As legislation increasingly addresses the whole-life carbon emissions of buildings, it is vital to develop cross-sectoral accounting methods that effectively measure and monitor the overall impact of buildings. Such methods are essential for creating sound and holistic decarbonization pathways that align with sustainability policies. This article aims to provide a consistent approach for depicting the life-cycle emissions of buildings at the national level, using France as a case study. By integrating the different emission scopes with decarbonization pathways, this approach also enables the creation of comprehensive whole-life carbon budgets. The results show that the French building stock footprint reached 162 MtCO2eq in 2019, with 64% attributed to operational emissions, primarily from fossil fuel combustion, and the remainder to embodied emissions, mainly from upstream industrial and energy sectors. Overall, 20% of the emissions occurred outside the national borders. Under various global decarbonization pathways, the significance of embodied emissions is projected to increase, potentially comprising 78% of the life-cycle emissions by 2050 under the current policies. This underscores the necessity for climate policies to address emissions beyond territorial and operational boundaries.

The past five decades have witnessed an unprecedented growth in population. This has led to an ever-growing housing demand. It has been proposed that the use of bio-based materials, and specifically bamboo, can help alleviate the housing demand in a sustainable manner. The present paper aims to assess the environmental impact caused by using four different construction materials (bamboo, brick, concrete hollow block, and engineered bamboo) in buildings. A comparative life cycle assessment (LCA) was carried out to measure the environmental impact of the different construction materials in the construction of single and multi-storey buildings. The LCA considered the extraction, production, transport, and use of the construction materials. The IPCC2013 evaluation method from the Intergovernmental Panel on Climate Change IPCC2013 was used for the calculations of CO2 emissions. The assessment was geographically located in Colombia, South America, and estimates the transport distances of the construction materials. The results show that transportation and reinforcing materials significantly contribute to the environmental impact, whereas the engineered bamboo construction system has the lowest environmental impact. The adoption of bamboo-based construction systems has a significant potential to support the regenerative development of regions where they could be used and might lead to long-lasting improvements to economies, environments, and livelihoods.