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Recently, there has been a shift toward the embodied energy assessment of buildings. However, the impact of material service life on the life-cycle embodied energy has received little attention. We aimed to address this knowledge gap, particularly in the context of the UAE and investigated the embodied energy associated with the use of concrete and other materials commonly used in residential buildings in the hot desert climate of the UAE.

Using input–output based hybrid analysis, we quantified the life-cycle embodied energy of a villa in the UAE with over 50 years of building life using the average, minimum, and maximum material service life values. Mathematical calculations were performed using MS Excel, and a detailed bill of quantities with >170 building materials and components of the villa were used for investigation.

For the base case, the initial embodied energy was 57% (7390.5 GJ), whereas the recurrent embodied energy was 43% (5,690 GJ) of the life-cycle embodied energy based on average material service life values. The proportion of the recurrent embodied energy with minimum material service life values was increased to 68% of the life-cycle embodied energy, while it dropped to 15% with maximum material service life values.

The findings provide new data to guide building construction in the UAE and show that recurrent embodied energy contributes significantly to life-cycle energy demand. Further, the study of material service life variations provides deeper insights into future building material specifications and management considerations for building maintenance.

The purpose of this paper is to identify the sustainability conditions of primary schools in Turkey within the scope of the life cycle assessment (LCA). It is aimed to develop optimum alternatives to reduce the environmental impact of primary schools and reach environmental sustainability targets of the sustainable development goals in Turkey.

From the construction project of 103 buildings located in Istanbul, 10 case buildings with various typical plans were chosen for analysis. The results regarding their life cycle energy and carbon emission for material production, operation and maintenance stages were calculated for a lifespan of 50 years. Results were evaluated and compared within the scope of environmental sustainability. Optimum alternatives for improving the environmental sustainability and performances of selected case buildings’ facades were developed, and the life cycle energy and carbon emission for proposed conditions were calculated. The obtained results were evaluated for current and proposed conditions.

Results showed that reinforced concrete material contributes the most to the life cycle-embodied energy and CO₂ emission of buildings. Cooling load increases the life cycle operational energy (LCOE) and CO₂ emission of buildings. Using high-performance glazing significantly reduces LCOE and CO₂ emission. Recycled and fiber-based materials have significant potential for reducing life cycle-embodied energy and CO₂ emission.

This study has been developed in response to achieving sustainable development targets on public buildings in Turkey. In this regard, external walls of primary schools were analyzed within the scope of LCA and recommendations were made to contribute to the policies and regulations requested by the Government of Turkey. This study proves that alternative and novel materials have great potential for achieving sustainable public buildings. The study answers to questions about reducing the environmental impact of primary school buildings by using LCA approach with a holistic point of view.

In recent years, fast urban expansion in China has stimulated rapid energy consumption growth and increased environmental pollution. Therefore, it is important to utilize clean and renewable energy in district heating for the sustainable urban development. This study aimed to investigate the environmental and economic impacts of one hot dry rock (HDR) geothermal energy-based heating system in a life cycle framework.

By using the input–output-based life cycle analysis model, the energy consumption, CO₂ emission and other pollutants of the HDR-based heating system were evaluated and then compared with those of other four heating systems based on burning coal or natural gas. The life cycle costs of the HDR-based heating system were also analyzed.

The results showed that using HDR geothermal energy for heating can significantly reduce fossil fuel consumption, CO₂ emission as well as environmental pollution, and its life cycle costs are also competitive.

This study not only evaluated the environmental and economic impacts of the HDR-based heating system in a life cycle framework but also provided a methodological life cycle assessment framework that can estimate both economic and environmental benefits, which can be used in policy making for China’s urban development.

This article surveys the literature dealing with theory and applications of life cycle costing (LCC). It deals with the literature published in the last 25 years and provides 667 references.

The recurrent embodied energy (REE) is the energy consumed in the maintenance, replacement and retrofit processes of a facility. The purpose of this paper was to analyze the relationship of REE with the service life and life cycle embodied energy. The amount of variation in the reported REE values is also determined and discussed.

A qualitative approach that is known as the literature based discovery (LBD) was adopted. Existing literature was surveyed to gather case studies and to analyze the reported values of REE.

The reported values of REE showed considerable variation across referred studies. It was also found that the reported REE values demonstrated a moderate positive correlation with the service life but a very strong positive correlation with the life cycle embodied energy of both the residential and commercial facilities.

This review paper pointed out the importance of the maintenance and replacement processes in reducing the life cycle energy use in a facility. Future research could focus on performing case studies to evaluate this relationship.

The findings highlight the significance of REE in reducing the life cycle energy impacts of a facility. As facility managers routinely deal with maintenance and replacement processes, they hold an important responsibility of reducing the life cycle energy.

The findings of the paper would motivate the facilities management professionals to prefer long service life materials and components during the postconstruction phases of a built facility.

The purpose of this study is to evaluate the sustainability performance of modular construction from a life cycle perspective. So far, the sustainability performance of modular buildings has been explored from a life cycle viewpoint. There is no comprehensive study showing which material is the best choice for modular construction considering all three sustainable pillars. Therefore, a life cycle sustainability performance framework, including the three-pillar evaluation framework, was developed for different modular buildings. The materials are concrete, steel and timber constructed as a modular construction method.

Transitioning the built environment to a circular economy is vital to achieving sustainability goals. Modular construction is perceived as the future of the construction industry, and in combination with objective sustainability, it is still in the evaluation phase. A life cycle sustainability assessment, which includes life cycle assessment, life cycle cost and social life cycle assessment, has been selected to evaluate alternative materials for constructing a case study building using modular strategies. Subsequently, the multi-criteria decision-making (MCDM) method was used to compute the outranking scores for each modular component.

The calculated embodied impacts and global warming potential (GWP) showed that material production is the most critical phase (65%–88% of embodied energy and 64%–86% of GWP). The result of embodied energy and GWP shows timber as an ideal choice. Timber modular has a 21% and 11% lower GWP than concrete and steel, respectively. The timber structure also has 19% and 13% lower embodied energy than concrete and steel. However, the result of the economic analysis revealed that concrete is the most economical choice. The cost calculations indicate that concrete exhibits a lower total cost by 4% compared to timber and 11% higher than steel structures. However, the social assessment suggests that steel emerges as the optimal material when contrasted with timber and concrete. Consequently, determining the best single material for constructing modular buildings becomes challenging. To address this, the MCDM technique is used to identify the optimal choice. Through MCDM analysis, steel demonstrates the best overall performance.

This research is valuable for construction professionals as it gives a deliberate framework for modular buildings’ life cycle sustainability performance and assists with sustainable construction materials.

Operational energy use in buildings accounts for 28% of global energy demand. One method to reduce operational energy is upgrading old appliances to more efficient ones. In Australia, the most common residential heating type is reverse-cycle heating, followed by gas heating. This article aims to determine the energy balance resulting from a gas heating upgrade through a life cycle assessment (LCA).

Extensive primary data were collected for operational energy performance of 61 ducted gas heating upgrades. To address the scarcity of data on material composition, one ducted gas heater was deconstructed and assessed in terms of material composition (types and weights). The comparison between embodied energy and operational energy savings allows us to establish whether operational energy savings offset the embodied energy incurred with the upgrade. The end of life stage of the old appliance, as well as the production, construction and use stage of the new appliance were assessed.

The results show that the operational energy savings offset the following impact categories: global warming, ozone layer depletion, aquatic acidification, nonrenewable energy and carcinogens. Only the mineral extraction is not offset by the operational energy savings. The results clearly demonstrate that operational energy savings outweigh the embodied energy and therefore contribute positively to the environment.

This study is the first to focus on the LCA of building services through extensive primary data collection and a focus on a high number of appliances. This supports ongoing energy efficient upgrades in Australia and paves the way for further, similar studies to confirm or disprove these findings in other parts of the world.

Energy analysis (EA) within a building information modelling (BIM) enables consistent data integration in central repositories and eases information exchange, reducing rework. However, data loss during information exchange from different BIM uses or disciplines is frequent. Therefore, a holistic approach for different BIM uses enables a coherent life cycle information flow. The life cycle information flow drives the reduction of data loss and model rework and enhances the seamless reuse of information. The latter requires a specification of the EA key performance indicators (KPIs) and integrating those in the process.

The paper presents a set of KPIs extracted from the developed EA process maps and interviews with expert stakeholders. These KPIs stem from the literature review and link to the benefits of EA through industry expert review. The study includes (1) development and validation of EA process maps adjusted to requirements from different stakeholders. (2) KPIs aligned with the EA process map, (3) identification of the drivers that can facilitate life cycle information exchange and (4) opportunities and obstacles for EA within BIM-enabled projects.

This paper depicts a viable alternative for EA process maps and KPIs in a BIM-enabled AEC design industry. The findings of this paper showcase the need for an EA within BIM with these KPIs integrated for a more effective process conforming to the current Open BIM Alliance guidance and contributing towards sustainable life cycle information flow.

The limitation of the research is the challenge of generalising the developed EA process maps; however, it can be adjusted to fit defined organisational use. The findings deduced from the developed EA process map only show KPIs to have the ability to facilitate adequate information flow during EA.

The AEC industry will benefit from the findings of this primary research as the industry will be able to contrast its process maps and KPIs to those developed in the paper.

This paper benefits the societal values in EA for the built environment in the design stages. The subsequent life cycle information flow will help achieve a consistent information set and decarbonised built environment.

The paper offers a practical overview of process maps and KPIs to embed EA into BIM, reducing the information loss and rework needed in the practice of this integration. The applicability of the solution is contrasted by consultation with experts and literature.

The energy required to operate office buildings has been the focus of much research in the past three decades. There have been limited attempts to quantify the embodied energy consumed in construction. Some embodied energy studies have been relatively detailed. But the energy embodied in fixtures, fittings and furniture which is used by occupiers of buildings is rarely mentioned. The potential significance of the energy embodied in fixtures, fittings and furniture has yet to be established. Aims to establish the likely importance of the energy embodied in fixtures, fittings and furniture relative to other life cycle energy requirements of office buildings in temperate climates. Implementation actions are suggested for the optimisation of the energy embodied in fixtures, fittings and furniture used in buildings. Assists facility managers and businesses with their decision making with respect to the environmental impacts associated with energy use throughout the life cycle of their buildings.

Crucial transition of the Indian residential building sector into a low-emission economy require an in-depth understanding of the potentials for retrofitting the existing building stock. There are, however, limited studies that have recognised the interdependencies and trade-offs in the embodied energy and life cycle impact assessment of retrofit interventions. This research appraises the life cycle assessment and embodied energy output of a residential building in India to assess the environmental implications of selected retrofit scenarios.

This study utilises a single case study building project in South India to assess the effectiveness and impact of three retrofit scenarios based on life cycle assessment (LCA) and embodied energy (EE) estimates. The LCA was conducted using SimaPro version 9.3 and with background data from Ecoinvent database version 3.81. The EE estimates were calculated using material coefficients from relevant databases in the published literature. Monte Carlo Simulation is then used to allow for uncertainties in the estimates for the scenarios.

The three key findings that materialized from the study are as follows: (1) the retrofitting of Indian residential buildings could achieve up to 20% reduction in the life cycle energy emissions, (2) the modification of the building envelope and upgrading of the building service systems could suffice in providing optimum operational energy savings, if the electricity from the grid is sourced from renewable plants, and (3) the production of LEDs and other building services systems has the highest environmental impacts across a suite of LCA indicators.

The retrofitting of residential buildings in India will lead to better and improved opportunities to meet the commitments in the Paris Climate Change Agreement and will lead to enhanced savings for building owners.