Building Cost Research Articles

ColoriSens: An open-source and low-cost portable color sensor board for microfluidic integration with wireless communication and fluorescence detection

Microfluidic colorimetric biosensors have shown promising potential for detecting metal cations, anions, organic dyes, drugs, pesticides. As for today, most colorimetric sensors are read by a smartphone or professional optical imaging system, and there is still a lack of an affordable and reliable colorimetric detector for the microfluidic chip. Integrating those reading and detection capabilities into a microfluidic system is essential for point-of-care (POC) detection and can enable more complex microfluidic operations, such as lab-on-a-chip experiments or programmable microfluidics. We developed an open-source colorimetric detection sensor board that can be integrated into the existing microfluidic system. This sensor board has a built-in UV source that enables fluorescence detection. With built-in USB and Wi-Fi connectivity and a set of simple APIs, microfluidic systems can communicate directly with this sensor board, even wirelessly. The sensor was designed for low-cost. With a total build cost of less than 12 EUR per unit, it is ideal for low-cost systems and DIY microfluidic users. Along with the sensor board, we also designed a companion microfluidic chip carrier cartridge which can be modified depending on the chip’s dimension. To demonstrate the sensor, we also developed a cross-platform open-source client application to demonstrate the communication APIs and the functionality of the sensor board.

Budget Travel in the Mediterranean: A Methodology for Reconstructing Ancient Journeys through Least Cost Networks

Least cost paths have been used extensively in the archaeological study of ancient routeways. In this paper the principal interest is less in tracing detailed paths than in modelling long-distance travel through an extensive network over land and water. We present a novel, computationally-efficient method for avoiding the direction-dependent, positive biases in least cost paths encountered in standard algorithms. A methodology for generating networks of such paths is introduced based on a trade-off between building and travel costs, minimizing the total cost. We use the Peutinger Table, an illustrated <em>itinerarium</em> of the Roman empire, to calibrate the parameter controlling network complexity. The problem of how to weight land versus sea travel costs in the network is tackled by comparing itineraries of Delphic <em>theoroi</em> of the third century BCE with solutions of the asymmetric travelling salesman problem, a classic graph theory puzzle.

Optimalni projekt drvenih konstrukcija izloženih djelovanju požara uporabom metaheurističkog algoritma

One of the major tasks of structural engineers is to reduce the building cost. Thus, an effective optimization of structural elements is gaining in importance every day. The teaching-learning-based optimization (TLBO), which is one of metaheuristic algorithms, for an optimum design and analysis of timber structures under fire in accordance with EN 1995 1-2 (Eurocode 5: Design of Timber structures - Part 1- 2 General structural fire design), is proposed in this study. The objective function in this algorithm is the building cost of timber structures under fire, considering premature collapse of the structure and limitation of fire spread. A structure made of wood is investigated under different times of fire exposure in order to determine the cross-section and wood type of structural elements. In conclusion, the cross section and strength of structural elements made of wood can be effectively and rapidly optimized with TLBO according to EN 1995 1-2.

Refurbish or replace? The Life Cycle Carbon Footprint and Life Cycle Cost of Refurbished and New Residential Archetype Buildings in London

The environmental performance of existing buildings can have a major role in achieving significant reductions in CO2 emissions: In the UK, around 75% 2050's housing stock has already been built. While building performance improvement efforts mostly focus on operational performance, buildings environmental impact is the result of processes that occur throughout their life cycle.To achieve significant emission reductions in an economically viable way, this study uses Life Cycle Performance approaches to carry a cross-comparison between the refurbishment and replacement of two housing archetypes in London: mid-terrace-house and a bungalow. Specifically, the study integrates Life Cycle Carbon Footprint (LCCF) and Life Cycle Cost (LCC) protocols (EN 15978:2011 and BS ISO 15686–5), thermal simulations (EnergyPlus), building generative design framework (PLOOTO - Parametric Lay-Out Organisation generator) and mathematical optimisation algorithms (NSGA-II).Results show that the optimal refurbishment archetypes generally performed better than replacements (Refurbishments LCCF ranges between 1,100 and 1,500 kgCO2e/m2 and LCC 440-680 £/m2, compared to that of the replacements scenarios, ranging 1,220-1,850 kgCO2e/m2 and 550-890 £/m2). The study also highlights benefit of incentivising re-use to achieve quicker emissions reductions. The study lastly discusses a range of embodied and operational performance issues.

The Energy Efficiency Post-COVID-19 in China’s Office Buildings

China promptly took the leading step to mitigate the spread of COVID-19, producing the first scientific guidelines assuming health above energy consumption and significantly changing HVAC/AHU operation. The research intended to fulfill the gap by measuring the impact of the guidelines on energy use intensity, CO2 emissions, and energy operation costs related to workplaces. The guidelines are long-term sector and industry trends following occupants’ health and safety concerns, and today they are applied to nursing homes. The research extended the study to post-COVID-19 scenarios by crossing those settings with published reports on telework predictions. The methodology resorts to Building Energy Simulation software to assess the Chinese standard large office building on 8 climate zones and 17 subzones between pre- and post-COVID-19 scenarios under those guidelines. The outcomes suggest an upward trend in energy use intensity (11.70–12.46%), CO2 emissions (11.13–11.76%), and costs (9.37–9.89%) for buildings located in “warm/mixed” to “subarctic” climates, especially in colder regions with high heating demands. On the other hand, the figures for “very hot” to “hot/warm” climates lower the energy use intensity (14.76–15.47%), CO2 emissions (9%), and costs (9.64–9.77%).

An Approach to Analyze Reliability Indices in Peer-To-Peer Communication Systems

In this work, the performance of a peer-to-peer (P2P) network has been discussed. As being one of the most promising technology in today’s world, P2P systems exploit computation, bandwidth and other resources at the edge of the Internet, with the lower cost of building and maintenance. In the past, a lot of research has been done to improve the reliability of P2P systems focusing on paradigms like- routing strategies, reliable file exchange, resource location and placement, security. However, not much effort has been focused on studying their overall reliability incorporating essential failure causes altogether. In this research work, the authors have designed a mathematical model for a P2P network using Markov Process to holistically determine the availability, reliability and MTTF (Mean time to failure) and examined the most vulnerable components in the system whose failure rates can be controlled to achieve a more reliable network. In such networks, performance is affected to some degree due to failure or disturbance in any component.

Identification and Categorization of Building Defects

The problem of building defects is one of the common problems that occur throughout the lifecycle of the building. The construction stakeholders consider it a critical issue that led to costs and time implications of reworks. Mostly, repairing construction defects requires a cost approximately ranging from 2.4% to 3.15% of the total cost of building. Therefore, the current study looks forward to discovering and classifying the common factors contributing to construction defects. To achieve this objective, the researcher adopted a qualitative method to collect and analyze the needed data through deep review of several previous studies that focused on the causes of building defects. Accordingly, this study identified 57 common contributing factors of building defects, which are classified into five groups according to their sources. These groups are Factors related to design, Factors related to construction, Factors related to materials, Factors related to human and External factors. Understanding the contributing factors of the building defects can help construction stakeholders take and develop various strategies to reduce the existence of defects in newly constructed buildings. Positively, the findings of this study could upgrade the management efficiency of the building defects assessment process in the future, which will help to avoid them as much as possible.

Challenges in reaching positive energy building level in apartment buildings in the Nordic climate: A techno-economic analysis

Buildings consume significant amount of final energy and they emit large amount of CO2 emissions. To address this issue, nearly zero energy buildings is becoming a common in many countries, while research is advancing towards the positive energy building (PEB) target by utilizing renewable energy that can support reducing the emissions from the building stock. The aim of this study, is to design and model a renewable-based energy system for a real demo apartment building in Nordics (Finland) in order to be a PEB, by exceeding the building’s heating, cooling and plug load demands. The novelty of this study is to assesses the fulfillment of the PEB level in cold climate, by simulating various technologies (such as photovoltaic-thermal (PVT) system, heat pump (HP), wind turbines, seasonal thermal energy storage etc.) their integration with the building, its controls strategies, types of load included in the energy balance and definition of building boundaries across which the balance is calculated. TRNSYS simulation software is mainly used for dynamic simulation of the energy system. The electricity import and export, the life cycle cost (LCC), and the onsite energy matching factors are calculated to estimate the performance of the proposed system. In addition, the challenges related to the building’s limited physical boundary are discussed. The results of this study shows that, if all the demands are included, i.e. heating, cooling and plug loads, then it is difficult to reach the PEB level. In this case, the investment cost in the energy system is around 47–62% of the LCC and the rest is the operational cost. On the other hand, the PEB level is relatively easier to achieve if the plug loads are excluded, then the investment cost is around 88–100% of the LCC and there can be positive cash flow due to larger energy export than import. The PEB level is possible to be achieved when all the demands are included if the building boundary is extended to a virtual boundary outside its physical boundary that allows the addition of more renewable generations or by changing the building’s shape that allows the more installations of renewables on the roof. In this scenario, the investment cost on the energy system is around 62–91% of the LCC. Compared to the building cost, the energy system cost is generally low, i.e. around 1.2–4.3% of the building cost.. It can be concluded that in the Nordic conditions, it is difficult to reach the PEB level for the buildings in urban areas if the all the building’s energy demands are included. Renewable energy generations, such as additional PVT and wind turbines, are needed to be installed in an extended (virtual) boundary of the building if the PEB criterion has to be met when considering all the energy demands. Investment cost of the renewable energy system is low compared to the building’s cost, therefore, such renewable-based solutions can be provided with small additional cost, along with the new building’s cost, so that PEB and carbon neutrality targets can be achieved.

Policy-Induced Suburbanization: Mass-Produced Housing and Location Choices in Tijuana, Mexico

ABSTRACT Mexican cities began an urban expansion process fueled principally by public mortgage supply in the early 2000s. The new urban landscape, comprising mass-produced suburban housing developments for low-income families, deepened socioeconomic differences. For years, developers have claimed land prices are the reason for suburban expansion in Mexico, not policy-enabled construction economies. This study tests the hypothesis that cost reduction strategies through scale economies explain the suburban location and the homogeneous landscape built under the reformed mortgage system. Using data on housing production costs for Tijuana, the results show that building homes using technology developed during policy implementation yields scale economies and reduces building costs. Additionally, statistics on housing developers’ location decisions illustrate how production economies have contributed to a landscape that increased segregation, exclusion, and housing vacancy in Mexican cities.

POS-652 THE DIRECT COST OF DIALYSIS IN SRI LANKA

Sri Lanka is a welfare country providing all healthcare facilities free of charge including dialysis. We assessed the direct cost of dialysis (haemodialysis-HD, continuous ambulatory peritoneal dialysis-CAPD and automated peritoneal dialysis-APD) in different settings of the country. For the government sector the consumables required for HD, CAPD and APD is uniform throughout all government institutions. We enlisted the consumables required for all dialysis types and obtained the cost from State Pharmaceutical Cooperation (SPC) and State Pharmaceutical Manufacturing Cooperation (SPMC). Calculation of machinery, water, electricity, building and human resource cost for HD in government institutions is shown in Table 01. For CAPD and APD as these are home based treatment modalities the contribution of human resources, electricity, water and building cost for government institutions is negligible. National Hospital Kandy (NHK) is the only government institution that carries out session by session (per cycle) payment scheme (which is also incurred by government) for HD. The payment for a HD session is LKR 3,750/=, which includes Dializer 1.5, Blood line and transducer, Bicarbonate 1A 5L, Bicarbonate 1B 10L, Fistula Needle 16G, disinfectants and HD machine cost. The charges for HD in the private sector was obtained from the 5 private sector hospitals and the mean value was obtained per session. However this does not include the labour cost part. Peritoneal dialysis is currently not carried out in private sector. For the government sector the consumables required for A digital treatment data management system exists only for APD. The costing for the initiation of HD, CAPD and APD was excluded. The LKR values for the final costs are converted to US$ considering exchange rate as 1US$=203.00 LKR.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Results attached (Tables 2 to 7) In Sri Lanka HD is the most expensive dialysis method for government institutions while APD is the cheapest. Per cycle payment method is the cheapest among HD costs. The requirement for a health center in institutions contribute for the high HD cost.

Challenges Faced in Prefabrication or Modular Construction

Abstract: The prefabricated materials used in construction has indeed been hailed amongst the most efficient approaches, there is a difficulty in implementing this process in the construction industry. The article included an outline of the obstacles and factors that influence prefabrication or modular construction in India. The issues of prefabrication and modular construction were investigated through case studies. Prefabricated elements have been demonstrated to be an efficient and efficient approach for improving productivity and the process of construction, as well as assuring the quality of construction &amp; reducing time and cost. However, there are a number of issues with this strategy in practise, including initial high building costs, lack of understanding of the prefabricated method of construction, technical and installation hurdles, and the inability to find prefabrication businesses locally. Because of the nature of the city and also the growing population, the use of such prefabricated materials in the construction of buildings is beneficial. Keywords: Prefabricated construction, Challenges, fabricated elements, Installation hurdles

Design morphology complexity and conceptual building project cost forecasting

PurposeThis research aims to develop conceptual phase building project cost forecasting models by exploring the relationship of existing plan shape complexity indices and general design morphology parameters with total construction cost.Design/methodology/approachPlan shape indices proposed to date by the literature for measuring building design complexity are critically reviewed. Building morphology is also dictated by town planning restrictions such as plot coverage ratio or number of storeys. This study analyses historical data collected from 49 residential building projects to develop multiple linear regression (MLR) and artificial neural network (ANN) models for forecasting construction cost. Existing plan shape coefficients are calculated to evaluate the geometrical complexity of sampled projects. Ten regression-based cost estimating equations are totally derived from stepwise backward and forward methods, and their predictive accuracy is contrasted: to performance levels reported in past studies and to ANN models developed in this research with multilayer perceptron architecture.FindingsAnalysis of plan shape indices revealed that 85.7% of examined past projects possess a high degree of design complexity, hence resulting in expensive initial decisions. This highlights the need for more effective early design stage decision-making by developing new building economic tools. The most accurate regression model, with a mean absolute percentage error (MAPE) of 19.2%, predicts the log of total cost from wall to floor index and total building envelope surface. Other explanatory variables resulting in MAPE values in the order of 20%–22% are total volume, volume above ground level, gross floor area below ground level, gross floor area per storey and total number of storeys. The overall MAPE of regression-based equations is 24.3% whilst ANN models are slightly more accurate with MAPE scores of 21.8% and 21.6% for one hidden and two hidden layers, respectively. The most accurate forecasting model in the research is the ANN with two hidden layers and the sigmoid activation function which predicts total building cost from total building volume (19.1%).Originality/valueThis paper introduces MLR-based and ANN-based conceptual construction cost forecasting models which are founded solely on building morphology design parameters and compare favourably with previous studies with an average predictive accuracy less than 25%. This paper is expected to be beneficial to both practitioners and academics in the built environment towards more effective cost planning of building projects. The methodology suggested can further be implemented in other countries provided that accurate and relevant data from historical projects are used.

Operational Energy and Carbon Cost Assessment Model for Family Houses in Saudi Arabia

In Saudi Arabia, housing projects account for almost half of the total electricity consumed by the construction industry because of the large number of housing projects compared to other types of buildings. This paper proposes a quantitative approach using a multiple linear regression assessment model to predict the energy cost and environmental cost of housing building in Saudi Arabia. It was developed to assist house owners in Saudi Arabia in estimating the monthly energy cost and associated operational carbon cost according to several predictor parameters. Based on related literature, these parameters were reviewed and discussed by experts from the Ministry of Housing. They included building location, wall type, number of occupants, window type, envelope insulation, building age, building area, number of air-conditioning units and their systems, and lighting system. The model development process included five main stages: collecting the energy and carbon cost data from completed operating housing units, categorizing the collected data based on parameters, diagnosing the quality of gathered data and filtering outlier data if any, building and generating a model, and lastly, testing and validating the model. More than 77 datasets were collected across the country during different times of the year. The findings of this study reveal that the relationship between the number of users and the building area with the energy cost is significant and that the number of users is more correlated to the energy cost than the age of the building or the number of central air conditioners installed. Moreover, the results show that the developed model has the ability to predict energy and carbon costs with high accuracy. The developed model serves as a decision support tool for householders and decision makers in the Ministry of Housing to control the predicted parameters. This would be beneficial for the housing unit owners for allocating constrained budgets.

Synergistic development of green building market under government guidance: A case study of Tianjin, China

Under the restriction of carbon neutral and carbon peak, the development of green building has become the strategic demand of most countries in the world. Despite the rapid development of green building in China, there are still some problems, such as insufficient market development force under the government's leadership, emphasizing design and neglecting operation. In order to realize high-quality synergistic development of green building market, this paper constructs a new synergistic development framework of green building market, establishes a tripartite evolutionary game model including local governments, developers and consumers, uses the analysis tool of evolutionary game theory and synergistic theory to explore the unilateral ESS and the system ESS of green building market. In order to verify the model, this paper adopts a case study method, takes a residential building project in Tianjin, China which has awarded a three-star mark in green building design evaluation as an example for numerical simulation, discusses the influence of government guidance on the system evolution trajectory, demonstrates the interactive process of stakeholders' behavior, and finds out the key factors affecting the system equilibrium strategy. The result shows that (1) the means of government guidance will affect the speed and result of system evolution; (2) the strategy of stakeholders depends on the comparison of costs and benefits; (3) the probability of ideal events is positively correlated with the economic benefits and negatively correlated with incremental cost of green building. This study can provide theoretical guidance for local governments, developers and consumers to make scientific decisions, and provide practical enlightenment for government to play a more active role in green building market.

Strengthening Taiwan’s Green Building Certification System from Aspects of Productivity and Energy Costs to Provide a Healthier Workplace

This study estimates the relationship between poor indoor environmental quality (IEQ) and the increasing labor costs in green buildings in Taiwan. Specifically, poor performance of IEQ including HVAC, lighting, and indoor air quality, influences the health and well-being of occupants and leads to worse productivity, ultimately causing increased personnel cost. In Taiwan’s green building certification (GBC) system, the energy-savings category is mandatory while the IEQ category is only optional. It means that certified building cases may not reach the expected level in IEQ. Thus, this study reviews the thermal environment, indoor air quality (IAQ), and illumination performances of IEQ-certified and non-IEQ-certified buildings in 20 green buildings. Building energy and IEQ simulations were conducted to analyze the relationships between indoor comfort, energy cost, and personnel cost in green buildings. The results show that IEQ-certified green buildings averagely perform better than non-IEQ-certified ones in the aspects of IEQ and building costs. Besides, 3 of 13 non-IEQ-certified green buildings undertake extremely high additional expenditure for the poor IEQ. The results correspond to some previous findings that green-certified buildings do not necessarily guarantee good building performance. This study further inspects the pros and cons of Taiwan’s GBC system and proposes recommendations against its insufficient IEQ evaluation category. As the trade-off of energy-saving benefits with health and well-being in green buildings has always been a concern, this study aims to stimulate more quantitative research and promote a more comprehensive green building certification system in Taiwan.

Comparison of the Embodied Carbon Emissions and Direct Construction Costs for Modular and Conventional Residential Buildings in South Korea

Modular construction is an innovative new construction method that minimizes waste and improves efficiency within the construction industry. However, practitioners are hampered by the lack of environmental and economic sustainability analysis methods in this area. This study analyzes the embodied carbon emissions and direct construction costs incurred during the production phase of a modular residential building and provides comparison to an equivalent conventional residential building. Major drawings and design details for a modular residential building in South Korea were obtained, and the quantity take-off data for the major construction materials were analyzed for a modular construction method and a conventional construction method using a reinforced concrete structure under the same conditions. Focusing on major construction materials during the production phase, the embodied carbon emissions assessment revealed that adopting a modular construction approach reduced the environmental impact by approximately 36%, as compared to the conventional reinforced concrete method. However, in terms of the direct construction cost, the modular construction was approximately 8% more expensive than the conventional reinforced concrete construction method.

Sensitivity analysis of capital and energy production cost for off-grid building integrated photovoltaic systems

This paper presents a methodology for performing sensitivity analysis on the capital and energy production costs of off-grid Building Integrated Photovoltaic (BIPV) systems. The different influencing parameters that are considered in this study are the daily electric load on the system, available sunshine hours, per unit costs of components, maintenance and replacement costs, several design and rating factors, interest rates, and carbon credits. The probabilistic-based Latin hypercube sampling (LHS) technique and log-log regression were used to develop the correlations for the capital cost and energy production cost of the system. The results were validated by comparing them with case studies available in the published literature. Then, a standardized version of the dataset was used to derive the elasticity constants associated with each parameter, which quantified the change in costs when the parameter value was increased by a unit percentage. The effects on the costs of increasing the parameters by 10% were quantified, ranked and compared. For the capital cost, the three most sensitive parameters were the daily electric load on system, the fudge factor and the available sunshine hours. In contrast, for the energy production cost, the three most sensitive parameters were the annual maintenance cost factor, the fudge factor and the interest rate. The correlation trends between these parameters and the costs were also plotted. Precautions and potential stakeholder actions for reducing the costs of off-grid BIPV systems are suggested.

АНАЛІЗ ЕНЕРГЕТИЧНИХ ХАРАКТЕРИСТИК БУДІВЛІ НАВЧАЛЬНОГО КОРПУСУ СКЛАДНОЇ КОНФІГУРАЦІЇ ІЗ РОЗРОБКОЮ ПРОПОЗИЦІЙ ПО ПІДВИЩЕННЮ ЕНЕРГОЕФЕКТИВНОСТІ

There are many approaches to assessing the energy performance of buildings. In Ukraine, previously, when developing the energy passport of buildings, a method based on stationary calculations using degree-days of the heating period was used. Then, for the tasks of energy certification of buildings, a national calculation method based on the monthly quasi-stationary method was introduced. The simplified hourly method of calculation allows to consider thermal inertia of protections. In recent years, the methods of dynamic energy modeling using software packages have become increasingly relevant, because it allows at the preliminary design stage to estimate energy costs for different building needs before and after the implementation of energy efficiency projects and provides the ability to create 3D models based on geometric and thermal parameters, tasks of different configurations and types of engineering systems of the building. To build an energy model, a training building was chosen to determine energy consumption indicators and identify measures that have the greatest impact on the energy performance of the building.Purpose. Evaluation of energy characteristics of the educational building of a higher education institution with modeling of energy consumption in specialized software, technical and economic evaluation of opportunities to increase energy efficiency.Research methods. Energy inspection of the object of research and technical and economic analysis with the use of engineering methods of calculation, experimental measurements of the parameters of the microclimate of the building with the use of laboratory equipment were performed. Simulations are used in specialized software products RETScreen, EnergyPlus, DesignBuilder.Result. With the help of the developed models the structure of energy consumption of the educational building is obtained and the assessment of energy saving potential is carried out; in case of implementation of the proposed measures it is expected to reduce the consumption of energy resources and monetary costs for their payment, as well as improve the quality of educational services. The research was conducted as part of a master's thesis.Scientific novelty. The technical potential of this software for modeling the energy performance of a building of complex configuration on the example of the educational building of the educational institution, analyzed the methods of processing initial data for programs, comparative analysis of calculation results for the actual condition of the building, baseline and after implementing energy saving measures.Practical significance. As a result of the research, the potential of using different software packages to perform applied research of the master's dissertation was determined and a project of complex thermal modernization of the building of the educational building was developed.

Models for estimating costs of public buildings maintaining – review and assessment

Models for estimating costs of public buildings maintaining – review and assessment

Sustainable prefabricated buildings: a holistic approach

Although modern prefabricated buildings may offer many advantages, such as a significant reduction in cost and time, improved quality and accuracy in manufacture, easy dismantle and reuse of its components, etc., they have not gained the attention they deserve in the construction market yet. In this paper, a holistic approach for the formation of prefabricated buildings of advanced performance is presented. Within this context, a new, innovative prefabricated building element is developed, designed to exhibit optimized structural, hygrothermal, energy, acoustic, fire and environmental performance. The improved properties of the building element are ensured by the proper configuration of the layers that compose it with respect to the design objectives; for example, in order to support the heat storage and the control of indoor temperatures, the integration of PCMs in the element's layers is investigated. Furthermore, in order to indicate the contribution of the new building element to the sustainability of the overall construction, the performance of a building formulated with the new element is analyzed in terms of energy and environmental behaviour. The new building element and construction system are expected to systemize the prefabricated element's production, leading eventually to the improvement of the building quality, as well as to the reduction of time and cost of building's erection. In parallel, the new certified and optimized building performance will increase the share of prefabricated buildings in the Mediterranean countries, where housing needs are gradually growing, while at the same time, energy efficient and environmentally friendly construction will be promoted.