Buildings, Volume 9, Issue 10 (October 2019) – 17 articles

The idea of sustainable smart city has extensive scientific literature where the architects’ role in designing built environments, being a physical platform for implementing “elderly-friendly” solutions, is poorly referenced. The main objective of the article is to define the role of architects in creating the image of sustainable smart cities, focusing on senior citizens. The paper surveys the available literature on the subject and describes pilot studies carried out at the indicative level among the students of one of architecture faculties in Poland, based on the design thinking method. The studies demonstrate how students imagine intelligent elderly-friendly cities in the future from the architects’ perspective. In addition, examples of other studies with the students of that faculty are presented. Following the analyses combining the conclusions of research and pilot studies with the students, a tabular summary of the architects’ tasks and roles were provided—these were divided into six building blocks of a smart city and as a reference to the elements shaping the image of cities, districts and buildings. This is a new, innovative classification of architectural issues. The perspectives for further desk research and field participatory research were indicated, which should, in the future, translate into a novel holistic approach to the problem. Full article

Prefabrication offers substantial benefits including reduction in construction waste, material waste, energy use, labor demands, and delivery time, and an improvement in project constructability and cost certainty. As the material cost accounts for nearly 70% of the total cost of the prefabrication project, to select a suitable material supplier plays an important role in such a project. The purpose of this study is to present a method for supporting supplier selection of a prefabrication project. The proposed method consists of three parts. First, a list of assessment criteria was established to evaluate the suitability of supplier alternatives. Second, Building Information Modelling (BIM) was adopted to provide sufficient information about the project requirements and suppliers’ profiles, which facilitates the storage and sharing of information. Finally, the Analytic Hierarchy Process (AHP) was used to rank the importance of the assessment criteria and obtain the score of supplier alternatives. The suppliers were ranked based on the total scores. To illustrate how to use the proposed method, it was applied to a real prefabrication project. The proposed method facilitates the supplier selection process by providing sufficient information in an effective way and by improving the understanding of the project requirements. Full article

Load forecasting plays a major role in determining the prices of the energy supplied to end customers. An accurate prediction is vital for the energy companies, especially when it comes to the baseline calculations that are used to predict the energy load. In this paper, an accurate short-term prediction using the Exponentially Weighted Extended Recursive Least Square (EWE-RLS) algorithm based upon a standard Kalman filter is implemented to predict the energy load for blocks of buildings in a large-scale for four different European pilot sites. A new software tool, namely Local Energy Manager (LEM), is developed to implement the RLS algorithm and predict the forecast for energy demand a day ahead with a regular meter frequency of a quarter of an hour. The EWE-RLS algorithm is used to develop the LEM in demand response for blocks of buildings (DR-BOB), this is part of a large-scale H2020 EU project with the aim to generate the energy baselines during and after running demand response (DR) events. This is achieved in order to evaluate and measure the energy reduction as compared with historical data to demonstrate the environmental and economic benefits of DR. The energy baselines are generated based on different market scenarios, different temperature, and energy meter files with three different levels of asset, building, and a whole pilot site level. The prediction results obtained from the Mean Absolute Percentage Error (MAPE) offer a 5.1% high degree of accuracy and stability at a UK pilot site level compared to the asset and whole building scenarios, where it shows a very acceptable prediction accuracy of 10.7% and 19.6% respectively. Full article

The scientific literature offers a wide range of studies evidencing the progress done in the retrofit actions dealing with the current building stock; however, renovations of hospitals are still an open field of research due to their typical complexity that is usually associated with a very challenging updating processes to maintain or increase operational level. The paper provides a synthesis of a study developed by a team of the Department of Architecture for Saint Orsola Hospital in Bologna with the scope to explore innovative retrofitting strategies. The brief provided by the management unit of the hospital was connected to the general renovation plan involving the entire site and particularly some existing buildings taking into account some limitations concerning budget availabilities and everyday activities needed to ensure acceptable service level for the end users. The design approach starts from defining a basic unit (a typical hospital room) that is deeply analyzed to report the starting conditions (indoor environmental parameters) and then used to simulate the potential impacts of retrofitting actions on its performances. The results allowed to parametrically develop a step by step strategy scaled on each building sector and on the building as a whole to evaluate the global impact on energy performances while considering time and costs of each retrofitting options. Full article

High Dynamic Range (HDR) imaging using a fisheye lens has provided new opportunities to evaluate the luminous environment in visual comfort research. For glare analysis, strict calibration is necessary to extract accurate luminous maps to achieve reliable glare results. Most studies have focused on correcting the vignetting effect in HDR imaging during post-calibration. However, the lens projection also contributes to luminous map errors because of its inherent distortion. To date, there is no simple method to correct this distortion phenomenon for glare analysis. This paper presents a parametric-based methodology to correct the projection distortion from fisheye lenses for the specific use in glare analysis. HDR images were captured to examine two devices: a 190° equisolid SIGMA 8 mm F3.5 EX DG fisheye lens mounted on a Canon 5D camera, and a 195° fisheye commercial lens with an unknown projection, mounted on the rear camera of a Samsung Galaxy S7. A mathematical and geometrical model was developed to remap each pixel to correct the projection distortion using Grasshopper and MATLAB. The parametric-based method was validated using Radiance and MATLAB through checking the accuracy of pixel remapping and measuring color distortion with Structural Similarity Index (SSIM). Glare scores were used to compare the results between both devices, which validates the use of mobile phones in photometric research. The results showed that this method can be used to correct HDR images projection distortion for more accurate evaluation of the luminous environment in glare research. Full article

The standard requirements for transverse steel reinforcement (TSR) confinement in reinforced-concrete (RC) columns are mainly to provide the following: ductile behavior, minimum axial load capacity of the column’s core, and prevention of longitudinal bars buckling. It is well-known that the passive confinement due the TSR action is less effective in high-strength concrete (HSC) compared to normal-strength concrete (NSC). Therefore, the TSR amounts required by the standards for HSC columns are high, and in some cases, especially in the lower stories columns of high-rise buildings, are impractical. This paper presents a new construction method using textile-reinforced concrete (TRC) as internal confinement together with reduced TSR amounts. Moreover, comparison of the proposed method with RC columns casted in fiber-reinforced polymer (FRP) stay-in-place forms as additional external confinement, is presented. Eleven large-scale column specimens were tested under axial compression. The results give an insight on the application feasibility of the proposed construction method. It is shown that the TRC-TSR dual internal confinement action can be an option to reduce the standard required TSR amounts while maintaining similar levels of ductile behavior. Full article

The article presents a comparative analysis carried out using three methods, determining the heat transfer coefficient U for a ceramic product modified with a phase change material (PCM). The purpose of the article is to determine the convergence of the resulting thermal characteristics, obtained using the experimental method, numerical simulation, and standard calculation method according to the requirements of PN-EN ISO 6946. The heat transfer coefficient is one of the basic parameters characterizing the thermal insulation of a building partition. Most often, for the thermal characteristics of the partition, we obtain from the manufacturer the value of the thermal conductivity coefficient λ for individual homogeneous materials or the heat transfer coefficient U for the finished (prefabricated) partition. In the case of a designed composite element modified with a phase change material or other material, it is not possible to obtain direct information on the above parameter. In such a case, one of the methods presented in this article should be used to determine the U factor. The U factor in all analyses was determined in stationary conditions. Research has shown a significant convergence of the resulting value of the heat transfer coefficient obtained by the assumed methods. Thanks to obtaining similar values, it is possible to continue tests of thermal characteristics of partitions by means of numerical simulation, limiting the number of experimental tests (due to the longer test time required) in assumed different partition configurations, in stationary and dynamic conditions. Full article

In the last decades, the possibility to use the inelastic capacities of structures have driven the seismic design philosophy to conceive structures with ductile elements, able to obtain large deformations without compromising structural safety. In particular, the utilization of high-strength elements combined with the purpose of reducing inertial masses of the construction has highlighted the second-order effect as a result of the “lightweight” structure’s flexibility. Computational aspects of inclusion of the second-order effects in the structural analysis remain an open issue and the most common method in the current design practices uses the stability coefficient $\theta$ The stability coefficient estimates the ratio between the second-order effect and lateral loads’ effects. This coefficient is used then to amplify the lateral loads’ effects in order to consider the second-order effects, within a certain range proposed by codes of practices. In the present paper, we propose a simple approach, as an alternative to the stability coefficient method, in order to take into consideration P-Delta effects for earthquake-resisting ductile frame structures in the design process. The expected plastic deformations, which can be assessed by the behavior factor and the elastic deformations of the structure, are expected to magnify the P-Delta effects compared to those estimated from an elastic approach. The real internal forces are approximated by modifying the stiffness matrix of the structure in such a way as to provide a compatible amplification effect. This concept is herein implemented with a three-step procedure and illustrated with well-documented case studies from the current literature. The obtained results show that the method, although simple, provides a good approximation compared to more refined and computationally expensive methods. The proposed method seems promising for facilitating the design computations and increasing the accuracy of the internal forces considering the second-order effects and the amplification from the inelastic deformations. Full article

This study presents an analysis of the impacts of climate change on thermal comfort and energy performance of residential buildings in Ghana, in sub-Saharan Africa, and explores mitigation as well as adaptation strategies to improve buildings’ performance under climate change conditions. The performances of the buildings are analyzed for both recent and projected future climates for the Greater Accra and Ashanti regions of Ghana, using the IDA-ICE dynamic simulation software, with climate data from the Meteonorm global climate database. The results suggest that climate change will significantly influence energy performance and indoor comfort conditions of buildings in Ghana. However, effective building design strategies could significantly improve buildings’ energy and indoor climate performances under both current and future climate conditions. The simulations show that the cooling energy demand of the analyzed building in the Greater Accra region is 113.9 kWh/m² for the recent climate, and this increases by 31% and 50% for the projected climates for 2030 and 2050, respectively. For the analyzed building in the Ashanti region, the cooling energy demand is 104.4 kWh/m² for the recent climate, and this increases by 6% and 15% for the 2030 and 2050 climates, respectively. Furthermore, indoor climate and comfort deteriorate under the climate change conditions, in contrast to the recent conditions. Full article

The article presents a practical implementation of the indoor quality model. The indoor environmental quality (IEQ) model, including its essential elements (TC_index—thermal comfort, IAQ_index—indoor air quality, AC_cindex—acoustic comfort and L_index—daylight quality), is used to evaluate a case-study single-family building built with the nearly zero energy (NZEB) standard. The results of comfort sub-indices based on the measured indoor parameters are aggregated into one IEQ_index value representing the predicted building occupants’ satisfaction in percentage terms. The author’s intention is to use the proposed model in broader civil and environmental engineering practice, especially in terms of supporting the energy performance certification. The results obtained using the IEQ model were also compared with the results obtained with a similar method based on the comprehensive assessment system for built environment efficiency (CASBEE) approach for the same building. Full article

Comfort in university dormitory buildings in Japan is under-investigated as compared to offices and residences. A winter field survey conducted in two university dormitories in Central Japan aimed at investigating the differences in thermal responses of occupants relative to nationality and; to estimate their neutral and comfortable temperature under identical climatic conditions. Acceptability of the indoor environment was invariably high. While evaluation and preference votes depended on nationality; thermal sensation vote did not. Both Japanese and non-Japanese subjects voted neutral at a mean indoor temperature of 22 °C. The estimated probability of voting neutral for Japanese subjects was highest (65%) from 19 °C to 22 °C, while for non-Japanese subjects it was highest (75%) at a wider range: From 19 °C to 24 °C. Japanese students were more sensitive of and more critical about their indoor environment as opposed to the internationals (adjusted regression coefficients 0.55/K and 0.20/K). Griffiths’ model estimated the comfortable temperature for non-Japanese subjects at a 2 °C wider range and at a 2 °C higher average than for Japanese subject. Neutral and comfortable temperatures observed and estimated in the study were split above and below the recommended temperature threshold of 20 °C for Japan in winter. Full article

Reflective roof membranes have been shown to lower air conditioning costs by reducing the influx of thermal energy through a roof assembly and into the building. However, there have been studies suggesting that reflective roofs in cold climates give rise to increased winter heating costs, due to the lack of absorption of solar thermal energy. Such studies could be used to justify continued use of dark, absorptive roof membranes even in areas that are striving to reduce urban heat island effects and/or lower contributions to global warming. In a prior modeling study, by this author and others, based on gas heat, it was found that reflective roofing provides net annual energy savings so long as air conditioning was used. Studies by others have suggested that when electric heat is used, the winter heating cost savings associated with non-reflective roofing outweigh summer air conditioning cost savings with reflective roofing. However, these studies did not take into account electric demand charges. Therefore, this present study modeled the energy efficiency of commercial buildings in order to compare the effect of gas versus electric heat with varying levels of demand charge included, on the net energy efficiency. Four different levels of demand charges were compared, along with three levels of solar reflectance for thirteen cities located throughout the US. In every studied case, when gas heat was assumed, net annual energy savings were predicted for reflective membranes. For electric heat, net energy savings were achieved in most cases even when demand charges were zero. In three northernmost cities, this was the case provided that demand charges exceeded a relatively small minimum. This finding suggests that reflective roofing provides for net energy efficiency improvements in most US cities and all cities when demand charges exceed USD 6.25 Therefore, efforts by cities to encourage reflective roofing as part of urban heat island effect mitigation programs should not be reduced. Full article

The legacy of built heritage is one of the most critical questions of our time—the objective of preserving its immaterial values and exploiting its original vocation brings about challenges related to the history, the identity, and the quality of life of the concerned territory. This especially applies to religious buildings given their strong bond with collective memory. The aim of this research is to determine whether allocating new uses that pursuit social benefits for the community is a possible implementation of the aforementioned purposes and whether it better addresses a broader view of sustainable development, which encompasses equity and well-being. The methodology combines careful knowledge of the building, comparing residual performances of the fabric with new functions. We present a case study, with focus on healthcare-related accommodation facilities and the issue of healthcare migration, which aims to convert a dismissed capuchin convent, located in Villagonia (Taormina, Italy), into a shelter house to host families whose relatives are being treated at the neighbourhood medical centre. This proposal shows that heritage buildings, especially religious ones, have outstanding material and immaterial potential and, through good reuse practices, they provide a valuable opportunity to address the overarching objective of social sustainability. Full article

In the recent decade, Building Information Modeling (BIM) has widely been adopted in the Architectural, Engineering and Construction (AEC) industry and completely upended the way we build. While BIM continues gain momentum in the industry, it has also attracted increasing attention from researchers. However, most of the current study focuses on reviewing BIM for management, BIM for green building, BIM for infrastructure and BIM for Facilities Management (FM). There are few studies about Global BIM review and to discuss their complex inter-connections. In this study, we adopted a scientometric analysis method to review global BIM research during 2004–2019. In total, 1455 scholarly bibliographic records obtained from Web of Science Core Collection database were established for the analysis. This study has identified the top productive and influential researchers, research institutes, regions/countries, subject categories and journals in the BIM field. In addition, 11 clusters of global BIM research were also identified including construction project, green BIM, construction safety planning, automated IFC-based workflow and so on. The authors distinguished 11 clusters of global BIM research into three stages, namely formulating stage, accelerating stage and transforming stage. Furthermore, the authors reviewed the BIM policy of Singapore and observed there is a co-production relationship between evolution of BIM policy and global BIM research. These findings provide valuable information for researchers, practitioners and policymakers by visualizing the current progress in the research field of BIM and highlighting future research needs. Full article

The experimental setup implements a simplified PASSYS test cell construction, which is combined with a detailed simulation to reduce measurement effort. To analyze the cell’s dynamic behavior, the test cell was closely monitored with thermal sensors, and different static and dynamic heating modes were applied during a three-week calibration period. Co-heating tests were performed for steady-state measurements and cyclic heating periods account for the transient behavior of the test cell. The cells response was compared to the results of transient simulations with the software packet Modelica. The equation based Modelica framework allowed a detailed transient thermal simulation of the test cell’s dynamic to be set up that shows close agreement with the measurements. In addition, the flexibility of Modelica allowed unforeseen events affecting the experimental setup to be replicated, thereby ensuring an uninterrupted heat flow history of all surfaces. More than 96% of the predicted air temperatures (1 min resolution) match the experimental values within an error band of ±1.5 K, and 90% of all predictions are within ±1.0 K. Full article

Airflow into stairwells due to stack effect is a concern affecting fire safety, energy performance, and indoor air quality. Stack effect in tall buildings can create significant pressure differentials in vertical shafts when differences in outdoor and indoor temperature exist. The pressure differentials drive air through openings or gaps in walls and floors. Vertical shafts, consisting of stairs and elevators, may transport significant volumes of air. During heating season, this results in the infiltration of cold air at lower floors and the exhaust of warm air on the upper floors. Correspondingly, it results in the spread of air and potential contaminants within the building. Stack effect driven airflow will change according to size and distribution of leakage paths. The size of leakage areas can be approximated by a cross-sectional area of an orifice that would allow equivalent flow. This leakage area is dependent on construction material, workmanship, and even operation, as openings from windows and doors equate to large orifices. A building’s composition of these leakage areas can greatly impact the effective area and airflow. The effect of openings from stairwell doors can change the Neutral Pressure Plane location (NPP), altering airflow patterns within a building. This paper investigates the influence of effective area on airflow within stairwells for multi-unit residential buildings (MURB) due to stack effect. A range of parameters reflective of industry standards are evaluated using network modeling and computational fluid dynamics (CFD). Parametric analysis is used to determine the sensitivity to which they affect airflow between building and stairwells. The effect of airflow within vertical shafts has consequences on indoor air quality (IAQ) and smoke spread, energy efficiency, and thermal comfort. The benefit of reducing leakage in buildings can be understood by comparing the quantity and patterns in airflow in and out of stairwells. Improving air tightness of the building envelope or vertical shafts can have a significant impact on airflow. Full article

Construction and demolition waste (C&D waste) are widely recognized as the main form municipal solid waste, and its recycling and reuse are an important issue in sustainable city development. Material flow analysis (MFA) can quantify materials flows and stocks, and is a useful tool for the analysis of construction and demolition waste management. In recent years, material flow analysis has been continually researched in construction and demolition waste processing considering both single waste material and mixed wastes, and at regional, national, and global scales. Moreover, material flow analysis has had some new research extensions and new combined methods that provide dynamic, robust, and multifaceted assessments of construction and demolition waste. In this paper, we summarize and discuss the state of the art of material flow analysis research in the context of construction and demolition waste recycling and disposal. Furthermore, we also identify the current research gaps and future research directions that are expected to promote the development of MFA for construction and demolition waste processing in the field of sustainable city development. Full article