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Sustainable building design suffers from a lack of reliable life cycle data. The purpose of this paper is to compare life cycle costs of sustainable building projects, examine the magnitude of various cost drivers and discuss the implications of an emerging shift in cost drivers.

This paper is based on data from 21 office buildings certified in Denmark according to the sustainable certification scheme DGNB.

The paper supports previous findings that construction costs and running costs each roughly make up half of the life cycle costs over a 50-year period. More surprising is the finding that the life cycle costs for cleaning are approximately twice as high as the supply costs for energy and water.

The data set is based on actual construction costs of office buildings constructed in 2013-2017. Although all running costs are calculated rather than measured, they are based on a more detailed, specific and industry-supported set of calculation assumptions than is usual for life cycle costing studies because of extensive collaborative work in a number of concomitant national research and development projects.

Authorities, clients and building professionals heavily emphasise energy-saving measures in new Danish buildings. The paper suggests redirecting this effort towards other more prominent cost drivers like cleaning and technical installations.

This paper provides a notable contribution to the academic understanding of the significance of different cost drivers as well as the practical implementation of life cycle costing.

The architecture, engineering and construction industry faces several challenges when performing life-cycle cost calculations. On the basis of activity theory, this study aims at improving our understanding of the current cost calculation in design practices as an activity system with a number of built-in contradictions.

Drawing on one of the authors’ practical experience from a design office, the research design comprises a paradigmatic case study of a Danish architecture firm, in which data are gathered through documents, observations, interviews and physical artefacts. Moreover, this paper applies a literature review on barriers for adopting life-cycle costing.

The paper identifies a number of primary, secondary, tertiary and quaternary contradictions between practices of design, cost calculations and data management. Thus, hypotheses are formulated on how and to what extent these different contradictions shape cost calculations in design practices to obstruct or support the application of life cycle costing principles in design.

This study is part of an ongoing research project. Thus, additional analysis is required before the authors may conclude on final results.

This paper identifies a number of factors that obstruct or support the implementation of life cycle costing in current design practices.

This paper provides new insights into the various contradictions that shape data management in architectural offices as a prerequisite for improving life cycle design practices.

The aviation industry has seen consistent growth over the past few decades. To maintain its sustainability and competitiveness, it is important to have a comprehensive understanding of the environmental impacts across the entire life cycle of the industry, including materials, processes and resources; manufacturing and production; lifetime services; reuse; end-of-life; and recycling. One important component of aircraft engines, integral rotors known as Blisks, are made of high-value metallic alloys that require complex and resource-intensive manufacturing processes. The purpose of this paper is to assess the ecological and economical impacts generated through Blisk production and thereby identify significant ‘hot-spots’.

This paper focuses on the methodology and approach for conducting a full-scale Blisk life cycle assessment (LCA) based on ISO 14040/44. Unlike previous papers in the European Aerospace Science Network series, which focused on the first two stages of LCA, this publication delves into the “life cycle impact assessment” and “interpretation” stages, providing an overview of the life cycle inventory modeling, impact category selection and presenting preliminary LCA results for the Blisk manufacturing process chain.

The result shows that the milled titanium Blisk has a lower CO₂ footprint than the milled nickel Blisk, which is less than half of the global warming potential (GWP) of the milled nickel Blisk. A main contributor to GWP arises from raw material production. However, no recycling scenarios were included in the analysis, which will be the topic of further investigations.

The originality of this work lies in the detailed ecological assessment of the manufacturing for complex engine components and the derivation of hot spots as well as potential improvements in terms of eco-footprint reduction throughout the products cradle-to-gate cycle. The LCA results serve as a basis for future approaches of process chain optimisation, use of “greener” materials and individual process improvements.

The purpose of this paper is to analyse the production cycle of glazed porcelain stoneware, from the extraction of raw materials to the packaging of the finished product, with the aim of verifying the effects of integrating an environmental impact assessment into the decision-making process for managing the life cycle, to make it economically and ecologically sustainable, in a holistic approach along the supply-chain.

The research is performed using the life cycle assessment and life cycle costing methodologies, to identify environmental impacts and costs, that occur during extraction of raw materials, transportation, ceramic tiles production, material handling, distribution and end-of-life stages within a cradle to grave perspective.

Through the use of a comprehensive analysis of the environmental impact assessment and related externalities, three possible strategic options to improve the environmental performance and costs of ceramic tile production were formulated, leveraging sustainability as a competitive advantage.

This exploratory research opens future lines of investigation, the first of which is to confirm the technological feasibility and market responsiveness to the three strategic solutions hypothesised thanks to the use of an innovative eco-design technique.

The research has allowed testing and validating the tools of environmental impact assessment (life cycle assessment) and economic impact assessment (life cycle costing as structured methodologies in a life cycle management framework, to help companies implement competitive strategies based on sustainability.

Transportation infrastructure asset management has long been an active but challenging problem for agencies, which urges to maintain a good state of their assets but faces budgetary limitations. Managing a network of transportation infrastructure assets, especially when the number is large, is a multifaceted challenge. This paper aims to develop a life-cycle cost analysis (LCCA) based transportation infrastructure asset management analytical framework to study the impacts of a few key parameters/factors on deterioration and life-cycle cost. Using the bridge as an example infrastructure type, the framework incorporates an optimization model for optimizing maintenance, repair, rehabilitation (MR&R) and replacement decisions in a finite planning horizon.

The analytical framework is further developed through a series of model variations, scenario and sensitivity analysis, simulation processes and numerical experiments to show the impacts of various parameters/factors and draw managerial insights. One notable analysis is to explicitly model the epistemic uncertainties of infrastructure deterioration models, which have been overlooked in previous research. The proposed methodology can be adapted to different types of assets for solving general asset management and capital planning problems.

The experiments and case studies revealed several findings. First, the authors showed the importance of the deterioration model parameter (i.e. Markov transition probability). Inaccurate information of p will lead to suboptimal solutions and results in excessive total cost. Second, both agency cost and user cost of a single facility will have significant impacts on the system cost and correlation between them also influences the system cost. Third, the optimal budget can be found and the system cost is tolerant to budge variations within a certain range. Four, the model minimizes the total cost by optimizing the allocation of funds to bridges weighing the trade-off between user and agency costs.

On the path forward to develop the next generation of bridge management systems methodologies, the authors make an exploration of incorporating the epistemic uncertainties of the stochastic deterioration models into bridge MR&R capital planning and decision-making. The authors propose an optimization approach that does not only incorporate the inherent stochasticity of bridge deterioration but also considers the epistemic uncertainties and variances of the model parameters of Markovian transition probabilities due to data errors or modeling processes.

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.

Recent legislation resulted in an elevation of operating and support (O&S) costs’ relative importance for decision-making in Department of Defense programs. However, a lack of research in O&S hinders a cost analyst’s abilities to provide accurate sustainment estimates. Thus, the purpose of this paper is to investigate when Air Force aircraft O&S costs stabilize and to what degree. Next, a parametric O&S model is developed to predict median O&S costs for use as a new tool for cost analyst practitioners.

Utilizing the Air Force total ownership cost database, 44 programs consisting of 765 observations from 1996 to 2016 are analyzed. First, stability is examined in three areas: total O&S costs, the six O&S cost element structures and by aircraft type. Next, stepwise regression is used to predict median O&S costs per total active inventory (CPTAI) and identify influential variables.

Stability results vary by category but generally are found to occur approximately five years from initial operating capability. The regression model explains 89.01 per cent of the variance in the data set when predicting median O&S CPTAI. Aircraft type, location of lead logistics center and unit cost are the three largest contributing factors.

Results from this research provide insight to cost analysts on when to start using actual O&S costs as a baseline for estimates in lieu of analogous cost program data and also derives a new parametric O&S estimating tool designed as a cross-check to current estimating methodologies.

Quality in the construction industry is an important issue yet ignored during the initial stages of the life cycle of a project, that is, the design and construction stage. The contribution of stakeholders, especially the architects is generally suspended though it has huge significance in terms of cost and time related to quality. This research endeavors to examine the issues related to the design and construction stages of the project from architects' purview, to understand the relative importance of these issues in the Indian construction industry.

The study of qualitative data conducted formed a basis for online quantitative data collection that was further analyzed with the help of cross-tabulation and multiple correspondence analysis methods.

The study concludes that the budget of a project is a corresponding factor related to quality concern for architects. The study also established that the quality issues corresponding to high budgets are closely related to the construction stage and are identified as preparation of checklist, and bidding process of hiring the contractor on the lowest bid.

The study is limited to analyzing the perspective of architects; however, other stakeholders of the construction industry may represent a different opinion.

This research emphasizes the importance of the client's role, and need for integration and coordination among stakeholders in the construction industry for effective quality control and management.

The research presents an exhaustive literature review on quality issues and its importance with respect to cost implications, standard practices, sustainability and the life cycle of the project.

This study describes how maintenance capability should be created during the design and construction phases of construction projects. Purpose of the abstract to define the elements for creating the maintenance capability and the process to be used in construction life cycle projects for buildings.

An inductive and qualitative research method was used to construct the proposed process based on the literature and 18 interviews in two large construction companies.

The results indicate that the maintenance phase is usually overlooked during the design and construction phases, and capabilities are not systematically built. In particular, processes are lacking in data management, causing severe problems in maintenance.

This study presents a process including key requirements and activities for creating maintenance capability in conjunction with the design and construction phases, which is novel to the literature. The validated process can be adapted based on the needs of the construction company.