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Purpose The purpose of this study is to identify key performance indicators (KPIs) for badminton halls and, through a case study, illustrate how the facilities performance of a university badminton hall can be evaluated from the user perspective. Design/methodology/approach After a desktop literature review, the findings were discussed by a focus group, and the discussion result formed the basis for establishing an analytic hierarchy of facilities performance for the badminton hall. Then, interviews were made with 169 badminton hall users to solicit their perceived facilities’ importance and performance levels of the hall. Using MATLAB, a computer program incorporated with an Analytic Hierarchy Process was devised to compute the importance weights of the performance attributes under assessment. The outcomes were interpreted using an importance-performance evaluation matrix. Findings A facilities performance hierarchy, comprising nine KPIs, was established for the badminton hall. The factors influencing the users’ perceptions, the importance and performance levels of the KPIs and the areas of the hall requiring improvements were identified. Research limitations/implications Future studies can take a similar approach of this study to develop KPIs and facilities performance hierarchies for other types of sports venues. Practical implications The method used to identify the improvements required for the badminton hall can be applied to investigations on other sports facilities. Originality/value The methodology of this research was first applied to study a badminton hall – as reported in this paper.

Road traffic noise control in urban green space is a big concern for urban designers and public managers. The introduction of water sounds into noisy environment has been proven effective based on the soundscape approach. To extend more effective and applicable strategies for water sound informational masking, the exploration of the spatial settings of virtual water sound playbacks in urban parks were conducted both in the laboratory and field settings. Three different spatial water-sound sequences were added into the virtual noisy environment through an immersive spatial audio system and the real urban green park through the digital audio programming of bluetooth loudspeakers. The mental activities and subjective feelings of two group subjects were evaluated by a portable electroencephalogram (EEG) measurement with a post-doc questionnaire. The better masking effects introduced by the spatial settings of water sounds had been confirmed from the results of more positive emotional feedbacks and more relaxed mental state revealed by the spectral power of alpha band across two experimental conditions. Especially, the two-position switching water sounds brought more attentional network activations. Moreover, more sensory accumulation effects reflected by the mental network activations were observed from the brain activities in the in situ measurement compared to laboratory-setting.

This paper studies the effects of neighbourhood views of densely packed high-rise buildings on human perceptions of oppressiveness and noise annoyance. Earlier studies have found that views containing close-by tall buildings would not only negatively affect annoyance induced by road traffic noises but also develop an oppressive feeling. However, there is very limited understanding about the extent to which views blocked by buildings with tight spacing and separation distance affects the responses of oppressiveness and noise annoyance. Moreover, few studies have explored the potential of vertical greening and façade condition on attenuating those responses. This study aimed at formulating multivariate models to predict the probability of evoking perceived oppressiveness and noise annoyance when exposed to blocked views from indoors in a canyon-like setting conditioned by those spatial and façade attributes at road traffic noise levels between 55 and 65 dBA. Sixteen audio-visual composite scenarios were presented to 53 participants through immersive virtual reality for annoyance and oppressiveness ratings. The results showed that the probability of high noise annoyance responses could be significantly lowered with a larger separation distance, the presence of vertical greening, and maintenance on building façades. In addition, decreasing noise level, increasing separation distance, presence of building spacing, vertical greening and well-maintained building façades were likely to reduce oppressive feeling. Further, the model revealed that participants had higher sensitivity to vertical greening than to the openness of view when perceiving noise annoyance. The effect of separation distance was significantly stronger on perceived oppressiveness than on noise annoyance.

This paper studies the effects of densely packed high-rise residential settings on human perceptions of oppressiveness and annoyance induced by road traffic noise. Earlier studies have discovered that negative oppressive feeling would be developed when people on the streets were surrounded by high-rises at proximity. However, little has been understood about whether the spacing between tall buildings and the distance separating them from the viewers living in opposite high-rises affect their perceptions of oppressiveness and noise annoyance. This study aimed at developing multivariate models to predict the probability of evoking the feeling of oppressiveness when dwellers come across views restricted and obstructed by closing-in high-rises, and the response of noise annoyance in relation to the visual attributes associated with the oppressing environment. 46 cases were used for statistical analyses after the recruits were successfully administered in 2 stages of laboratory experiments where they were exposed to 12 scenarios through projected composite images and to 18 scenarios experienced in immersive virtual reality. The results showed that separation distance and building spacing were inversely related to perceived oppressiveness and noise annoyance. Further, the models revealed that participants implicitly were willing to trade off 4 m of spacing for extending 15 m of separation distance, and 60 m of separation distance for reducing 5 dB(A) in sound pressure level.

The elderly is a main user group of open space. Well maintained open spaces can increase their physical health and well-being. It is recognized that thermal perception has an essential impact on people's outdoor activities and use of open space. However, the specific association between influencing factors and the elderly's thermal perception and use of open space has not yet been fully investigated. On-site measurements of thermal conditions were carried out and 485 questionnaire surveys were conducted in six parks in two districts in Hong Kong. The ordered probit model and the binary logistics regression model were employed to investigate the relationship between the factors and the elderly's thermal perceptions, using the measure of thermal comfort, thermal sensation and thermal acceptability and use patterns and satisfaction with using open space. The study adopted a comprehensive framework, which included individual, physical and social and psychological factors. The results show the factors which influence the elderly’s thermal perceptions vary in the winter and summer and there is a significant association between thermal acceptability and satisfaction with open space. Under the trend of global warming, more attention should be paid to mitigate summer heat stress in outdoor space. The empirical findings of the elderly’s thermal perceptions and use patterns of parks in the summer provide insight for urban planners when considering flexible and responsive designs that reflect the special needs of the elderly.

Road traffic noise is responsible for several negative health effects for citizens in modern cities. Inside urban parks, which citizens use for social inclusion and cohesion, psychological and physical restoration, and physical activities, road traffic noise may significantly reduce the potential of these places to induce or enhance well-being. Although access restriction schemes and screens could be effective solutions to limit noise inside urban park areas, preserving their potential regenerative role may engender mobility, social, aesthetic, and architectural issues. Due to the positive effects that natural elements and water sounds can have on human perception, and based on the previous findings of the beneficial effects of audio-visual installations, this paper investigates the possibility of using audio-visual installations that simply evoke some natural features to improve the restoration of individuals inside urban parks. The study has been carried out using immersive virtual environments in two different experimental laboratory sessions in Hong Kong (China) and Aversa (Italy). The results showed that the positive effects provided by evocative installations were similar to those provided by traditional installations. Furthermore, the effects on the restoration increased as the installations became larger and included enveloping shapes. Furthermore, we found that the amount of evocative water installations’ material was responsible for changes in restoration. In contrast, the Chinese groups were less influenced by these installations.

Based on data collected in 20 A-level high-rise commercial concrete buildings in Hong Kong, the research successfully established a probability density function model, which is used to describe the carbon emissions profile of a commercial building. Results indicate that the superstructure of a commercial building, on average, had a footprint of 226.65 kg CO2/m2 and 10.6 kg CO2/m2 separately in the material use stage and transportation stages. It also evaluates the carbon emissions of various building elements and divides them into three levels according to the magnitude of their contribution. The results show that upper floor construction and external wall in Tier 1 contribute nearly 80% of emissions and should be of great concern. In addition to the probability density function model, a regression model was also successfully established in the study to predict carbon emissions. Research has shown that building layers and gross floor area can predict carbon emissions per unit area, and there is a positive relationship between the independent variable and the dependent variable. The regression model can help building designers determine design options to reduce carbon emissions in the early stages of design.

Institutions of higher education across the globe have commenced the appraisal of their sustainability performance via the utilization of various existing campus sustainability assessment tools. A comprehensive review of these existing tools reveals insufficient utilization of weighting methods and theoretical approaches that allow for the monitoring, review, and enhancement of the appraisal process and tools. Social media and spatial-based indicators usage are also deficient in the existing tools. This paper addresses these research gaps and develops a Modifiable Campus-wide Appraisal Model (MOCAM) for a comprehensive spatial-based information and assessment framework for policymakers, local authorities, and campus planners in countries with unknown campus sustainability status. In this model, the specific, measurable, achievable, relevant, and time-bound (SMART) approach was utilized to identify environmental-dimension indicators with campus-wide and spatial-based attributes. The Twitter social media platform, Elastic stack, and Python Library were used for the extraction and analysis of local stakeholders&rsquo, user-generated content for the identification of localized indicators. The analytic hierarchy process was used for the determination and analysis of the attribute level of importance and weights. The model also broadens the application of symbolic interactionism by translating it from the predominant field of social science to sustainable campus appraisal.

This paper studies the effect of human perception of visual and audio settings in an urban environment on annoyance. Video clips were projected onto a window panel of a living room to simulate neighborhood views containing different percentages of sea, mountain greenery, and road. These video clips were combined with audio stimuli corresponding to the congruent traffic and sea sounds. 246 participants were presented with 11 audio-visual stimuli and requested to respond to questions after the presentation. The collected responses were used to formulate a multivariate ordered logit model to predict the probability of evoking a high annoyance response. The findings revealed that views embracing mountain greenery close-by could enhance annoyance, which is contrary to other findings that greenery could always moderate noise annoyance. In addition, a 60% sea view was found to be able to yield 1 dB equivalent reduction in total sound pressure level. The trade-off was comparable to that achieved by having sea sound at a level 5 dB higher than road traffic noise. Exposure to road traffic noise level being 3 dB higher than sea sound level (i.e., signal-to-noise ratio = -3) together with a 60% sea view could provide an additional 1.5 dB equivalent reduction.

This paper explores the existing social life cycle assessment (SLCA) literature (theoretical and case studies) from decision making perspective. In order to tackle this, a critical review of 90 published work, including journal papers, conference proceedings and book chapters was undertaken. The selected articles were analyzed with a focus on methodological framework, boundary scoping, data inventories and practices. The analysis highlighted the inadequacies in the existing frameworks in terms of flexibility, conflicts in choosing and defining Area of Protection (AoP). Lack of consideration of social conditions of stakeholders in no-work and no-use phase, lack of inclusion of positive impacts, less attention to suppliers and consumers and choice of subjective indicators are highlighted as some weak portions within the boundary scoping. Less coverage of contextual and indirect indicators, and absence of documentation of a link between data collected (subjective indicators) and product activities are highlighted as a limitation within inventories, and finally within practices, lack of benchmarks is highlighted. This analysis highlighted an important differentiating factor between the actual definition of sustainability (maintenance of stocks for future generation) and the most common interpretation in literature as a summation of the three (social, environmental and economic) indices.

Walking has been actively advocated as a simple and effective means to boost individuals' physical activity levels. Comfort, as one of walking needs, is also the major objectives for many street design guidelines and walking audit tools. However, a few studies only identified the major environmental factors in a piecemeal manner without providing an integrated view on pedestrian comfort for recreational walking. This study aimed to identify the major micro- and built environmental factors and reveal their relative importance. 420 questionnaire responses with concurrently monitored micro-environmental conditions were analyzed to formulate a path model that portrayed the interrelationships between pedestrian comfort, and perceptual and objectively measured street built and micro-environmental characteristics. Our results showed that pedestrian comfort could be directly evaluated by pedestrians' satisfaction of built environment, thermal sensation, perceived air quality and loudness. The influence of satisfaction of built environment alone was found to be comparable to the aggregate influences of thermal sensation, perceived air quality and loudness. Thermal sensation, perceived air quality and loudness were found to mediate the associations between objectively measured parameters and individual recreational walking comfort respectively. The findings provide valuable insights for urban planners to improve the comfort level of recreational walking in streets.

People in an urban environment are exposed to different types of natural and man-made sounds. Human sound perceptions due to exposure to a single noise source, in particular road traffic and aircraft noises, have been investigated for a long time. However, only very few studies have been focused on exposure to a combination of sound sources. Also, there is a lack of multivariate models that can help to predict the preferences or annoyance responses as a result of adding a wanted sound to an unwanted sound. Accordingly, this study aimed at developing a multivariate model to predict the probability of invoking a high noise annoyance response due to combined water sound and road traffic noise exposure. A series of laboratory experiments were performed. Participants were presented with a series of acoustical stimuli before being asked to assign their annoyance ratings. Results suggested that other than acoustical properties like sound pressure levels, personality traits were found to exert considerable influences on the maximum likelihoods of the model prediction and thus should not be excluded from the model specification form. Also, the quality of the acoustical environment could be improved by adding water sounds to road traffic noises at high levels. The capability of stream sound to moderate noise annoyance was found to be slightly stronger than that of fountain sound. In addition, the formulated multivariate model enables to reveal the tradeoff decisions performed by people. An increase in the SPL of road traffic noise by 1 dB was considered to be equivalent to a reduction in the SPL of water source by 1.7 dB for a given probability value. Results arising from this study should provide valuable insights on understanding how humans respond to the combined water sound and road traffic noise exposure.

The importance of non-acoustical factors including the type of visual environment on human noise perception becomes increasingly recognized. In order to reveal the relationships between long-term noise annoyance and different types of neighborhood views, 2033 questionnaire responses were collected for studying the effect of perceptions of different combinations of views of sea, urban river, greenery, and/or noise barrier on the annoyance responses from residents living in high-rise apartments in Hong Kong. The collected responses were employed to formulate a multivariate model to predict the probability of invoking a high annoyance response from residents. Results showed that views of sea, urban river, or greenery could lower the probability, while views of noise barrier could increase the probability. Views of greenery had a stronger noise moderation capability than views of sea or urban river. The presence of an interaction effect between views of water and views of noise barrier exerted a negative influence on the noise annoyance moderation capability. The probability due to exposure to an environment containing views of noise barriers and urban rivers would be even higher than that due to exposure to an environment containing views of noise barriers alone.

This paper studies the effects of neighborhood views of densely packed high-rises on annoyance induced by road traffic noise. Earlier studies have found that views containing close-by buildings would negatively affect noise annoyance. However, there is limited understanding about the extent to which views constrained by closely spaced buildings at close proximity affect noise annoyance. Few studies explored the potential of vertical greening and façade appearance in attenuating noise annoyance responses. A multivariate model was formulated to predict the probability of evoking noise annoyance when exposed to views conditioned by space, façade and noise attributes. 50 participants were presented with 16 audio-visual composite scenarios through immersive virtual reality for noise annoyance ratings. The results showed that noise annoyance could be significantly lowered with reduced noise level, increased separation distance, the presence of vertical greening, and refurbishment on building façades. Participants were also found to have higher sensitivity to vertical greening than to the openness of view when perceiving noise-induced annoyance.

Recently, greater attentions have been started to put on the end-of-life (EoL) phase of buildings. Recycling, reuse and incineration of deconstructed wastes can help relieve the landfill burden and recover some energy from existing building materials in order to reduce environment impacts and/or reduce energy consumption. Life cycle energy assessment (LCEA) was performed for the EoL phase of a high-rise concrete office building in Hong Kong. The amount of energy that could be saved at the EoL phase through implementation of a specific EoL management strategy was evaluated in terms of energy saving potential (ESP), which was defined as the percentage of energy savings from the salvage materials to the total embodied energy of the building during its initial construction. Recycling of aluminum (30.7% ESP) and recycling of external walls (30.6% ESP) contributed to most of the total energy saving. Maximum reuse provided higher energy savings than maximum recycling (38.5% vs 35.9% ESP), while maximum incineration was not able to bring any energy saving (−44.8% ESP). In addition, the best EoL management strategies for different materials and elements were found to vary with time after taking the remaining proportions of embodied energy into considerations. Implementing the best EoL management strategies for different materials gave an ESP of 54.4% for 50-year life span. The life span of a building exerted considerable influences on the amount of energy saving. Highest energy saving was gained by implementing the best EoL strategies for 70-year life span.

This study formulated a new index for evaluating both the air quality and wind comfort induced by building openings at the pedestrian level of street canyons. The air pollutant concentrations and wind velocities induced by building openings were predicted by a series of CFD simulations using ANSYS Fluent software based on standard k-ɛ model. The types of opening configurations investigated inside isolated and non-isolated canyons included separations, voids and permeable elements. It was found that openings with permeability values of 10% were adequate for improving the air quality and wind comfort conditions for pedestrians after considering the reduction in development floor areas. Openings were effective in improving the air quality in isolated canyons and different types of opening configurations were suggested for different street aspect ratios. On the contrary, openings were not always found effective for non-isolated canyons if there were pollutant sources in adjacent street canyons. As such, it would also be recommended introducing openings to adjacent canyons along with openings to the target canyons. The formulated index can help city planners and building designers to strike an optimal balance between air quality and wind comfort for pedestrians when designing and planning buildings inside urban streets and thus promoting urban environmental sustainability.

The growing worldwide awareness of the significant impacts of physical activities on physical and physiological health has aroused great interest in the role of the physical built environment plays in walking and cycling activities. This comprehensive review shows how specific details of the built environment enhance people's walking and cycling. This was accomplished through identifying the barriers to walking and cycling activities as well as the general and specific characteristics of the major physical built environment attributes within a residential neighborhood that can help overcome these barriers and enhance the walking and cycling activity levels. Also the effectiveness of some individual attributes was also compared. Of particular value of this study is that its structure and level of details of information laid out in this review can facilitate building designers and neighborhood planners in creating a supportive environment within residential neighborhoods.

This paper studies the effects of park and surrounding building configuration on thermal comfort in parks. Simulation models have been formulated using ENVI-met to evaluate the thermal comfort during sunlit and non-sunlit periods for both summer and winter under various microclimatic conditions and park and surrounding building configurations in Hong Kong. The simulation results were then used to formulate regression models to reveal the relative importance of microclimatic and park and building configuration factors. Our results suggested that solar altitude and tree coverage were the most significant microclimatic factor and park and building configuration factor respectively during sunlit periods for both summer and winter. During non-sunlit periods, air temperature surpassed solar altitude to become the most significant factor. During sunlit periods, park and building configuration exerted considerable influences on thermal comfort in parks for both summer and winter. However, the park and building configuration factors that could enhance the thermal comfort in parks were quite different between summer and winter. For example, park area was a significant factor in summer, while building spacing and length-to-width ratio of the park only were significant factors in winter.

Despite the plethora of comprehensive review of campus sustainability assessment tools, reporting, and indicators in the extant literature, studies are absent specifically on campus-wide and spatial-based indicators in existing tools. Although, several academic campuses across the globe are located on a vast area of land with multiple activities and operations associated with serious ecological consequences. This paper explores the environmental-dimension indicators with spatial and campus-wide attributes in 13 existing campus sustainability appraisal tools via coverage evaluation and the SMART approach. The findings reveal a severe absence of comprehensive coverage of spatial-based indicators and the lack of the integration of a GIS and or related spatial software in their appraisal process. The article demonstrates how integrating GIS and or other related spatial techniques and software into environmental dimension indicators with campus-wide and spatial attributes could be carried out to remedy the challenges of absence, inadequate of or restrained access to basic information for campus sustainability appraisal project in developing world.

The impact of visual environment on human noise perceptions has always been under scrutiny. Two consecutive sets of laboratory experiments were performed for studying the effect of visual perceptions of different percentages of sea, greenery, and/or road views on noise-induced annoyance responses as well as preference ratings. Both experiments were carried out in a room purposely constructed inside an anechoic chamber to mimic the living room setting of a dwelling in Hong Kong. Video clips were projected consecutively onto the exterior window panel of the living room to simulate neighborhood views containing different percentages of sea, greenery and road. 82 and 58 participants were successfully administered in two experiments. Each participant was presented with 11 video clips and requested to respond to a series of questions regarding perceived noise annoyance and view preferences after presentation of individual clips. The responses collected from each experiment were employed to formulate ordered logit models to predict the probability of evoking a high annoyance response. Findings indicated that participants tended to prefer the presence of sea rather than that of either mountain or trees in views containing a trafficking road. Views containing sea would produce an attenuating effect on noise annoyance while views containing road would produce an aggravating effect. However, the size of the effects did not vary between 0% and 30% sea, or between 30% and 60% road contained in a view. Views containing dense greenery at a close distance would aggravate noise annoyance irrespective of form. However, when the percentage of greenery increased from 30% to 60%, the noise annoyance attenuating effect increased in the case of wooded mountain but decreased in the case of the more transparent tree clumps.

Economic incentives are widely used to promote green buildings (GB) and consume social resources. However, few studies evaluate the costs and benefits of implementing economic incentives, including hidden costs and benefits. This paper applies cost&ndash, benefits analysis (CBA) and transaction cost (TC) theory to systematically evaluate the costs and benefits of implementing the green building economic incentives, with focused study on the Gross Floor Area (GFA) Concession Scheme in Hong Kong. The data of costs and benefits indicate how the GFA Concession Scheme motivates stakeholders and how much it benefits the built environment, which provides a solid foundation for the improvement of the GFA Concession Scheme. Expert interviews were conducted to verify and compliment the new CBA framework and provide empirical evidence for policy-makers and researchers to better understand the allocation of costs and benefits. The results show that the effectiveness of the GFA Concession Scheme is readily justified even if it has caused a lot of extra transaction costs and actual costs. A 10% GFA concession attracts developers to enter the GB market but discourages them to go for a higher level of GB. It is the right time to differentiate the GFA concession to promote a higher level of GB.

Bulk of construction wastes generated through the dismantling process in a building redevelopment project creates many environment problems. Greater efforts are needed to put on the End-Of-Life (EOL) of building materials. Recycling, reusing and recovering of demolished wastes can either help relieve the landfill capacity or ‘regain’ some energy from existing building materials in order to reduce the embodied energy use for in the next new built building. This paper proposes to use ‘energy saving potential’ to quantify the amount of energy at the EOL phase that can be made usable in the building new life. Life cycle energy assessment was performed for the end-of-life phase of a high rise concrete commercial building. The energy associated with different waste management strategies was calculated to identify the options that can produce the highest energy saving in embodied energy. Recycling was found to have the highest energy saving potential of 53% while the energy saving potential of reusing was 6.2% and that of incineration was only 0.4%. Recycling strategy should be implemented for the building elements containing large amount of concrete (e.g. upper floor construction). Reusing instead of recycling should be adopted for the building parts with high aluminium content (e.g. windows).

This paper provides a review on three streams of life cycle studies that have been frequently applied to evaluate the environmental impacts of building construction with a major focus on whether they can be used for decision making. The three streams are Life Cycle Assessment (LCA), Life Cycle Energy Assessment (LCEA) and Life Cycle Carbon Emissions Assessment (LCCO2A). They were compared against their evaluation objectives, methodologies, and findings. Although they share similar objectives in evaluating the environmental impacts over the life cycle of building construction, they show some differences in the major focuses of evaluation and methodologies employed. Generally, it has been revealed that quite consistent results can be derived from the three streams with regard to the relative contribution of different phases of life cycle. However, discrepancies occur among the findings obtained from the three streams when different compositions of fuel mixes are used in power generation, or when the overall impacts are not contributed mostly by greenhouse gases emissions. The use of different functional units in different studies also makes it difficult to compare results with benchmarks or results from previous studies. Besides, there are drawbacks in boundary scoping, methodology framework, data inventory and practices which impair their usefulness as a decision making support tool for sustainable building designs.

This study aimed to explore people's perception of tree planting in street canyons and the perceived tree impacts through a questionnaire survey. Also, by using a discrete choice experiment, it aimed to reveal how people performed tradeoffs among three streetscape attributes: namely permeability (i.e. spacing between buildings), aspect ratio (i.e. ratio of street width to building height), and tree planting. A secondary aim was to determine respondent's willingness to pay for streetscape features and tree planting. Despite published research results that indicate tree planting can have a negative impact on air quality, the survey results from 509 respondents in Hong Kong indicated that the majority of them held positive views of tree planting in street canyons. The probability of having an overall positive view was found to be higher if an individual perceived that trees could improve air quality, provide shading or did not obstruct footpaths. The preferred streetscape was high permeability, regardless of whether respondents thought that trees could or could not contribute to improving air quality. However respondents who perceived that trees could improve air quality preferred tree planting at both sides of the street over lower aspect ratio whereas those who perceived that trees did not improve air quality preferred low aspect ratio over tree planting at both sides of the street. Both sets of respondents did however agree on the preferred order of tree planting options, namely planting on both sides of the street was preferred to planting at the center of the street which in turn was preferable to no tree planting at all. The overall willingness to pay was estimated to be HK$163.4, HK$132.4 and HK$121.1 per month for high permeability, street-level tree planting and low aspect ratio, respectively. The study clearly identifies high permeability as the most preferred planning option. However, the perception held by the majority of respondents that trees can improve air quality is contrary to recent research findings. This poses a dilemma for urban planners in that schemes that may be more beneficial, i.e. low aspect ratio, may face more public opposition than less beneficial schemes involving tree planting. Although the study was conducted in Hong Kong the findings should be applicable to other modern metropolises characterized by high rise buildings.

This study has successfully formulated artificial neural network models to predict thermal comfort evaluation in outdoor urban parks in Hong Kong, a sub-tropical city, for both summer and winter periods. The artificial neural network models embracing two-hidden layers outperformed other types of commonly adopted thermal comfort models. The model prediction performance was considerably improved by including perceptions of microclimate, perceptions of environmental features and personal traits as additional predictor variables. Sensitivity analysis determined that thermal sensation is the most important factor influencing thermal comfort evaluation in outdoor urban parks, followed by air temperature for both summer and winter. Solar radiation is another important factor immediately following air temperature for winter. In contrast, perceived density of trees and perceived number of water bodies in a park were found to be more important than solar radiation for summer. The findings arising from this study should provide valuable insights for formulating effective strategies for improving the thermal environment in urban parks in different seasons.

This study applied the Monte Carlo method to generate probabilistic distributions for describing the CO2 footprint of the superstructure of a high-rise concrete office building. The distribution profile was constructed with the material-use data collected from 13 high-rise concrete office buildings in Hong Kong. Results indicated that the average carbon footprint of the superstructure of an office building was 215.1 kg CO2/m22. External walls and upper-floor construction had the highest CO2 footprint, followed by suspended ceilings and finishes. These three elements altogether accounted for an average of 84.2% of the CO2 footprint associated with the superstructure. Also, this study evaluated the emissions-reduction impacts of five different material-use options over a 60-year lifespan. Among all the studied options, the most effective option was to maintain 15–30% of the existing structural and nonstructural building elements as this could reduce the CO2 footprint by 17.3%. Diverting construction wastes to recycling could reduce the CO2 footprint by 5.9%. Reusing resources and importing regional materials could only reduce the CO2 footprint by 3.2% and 3.1%, respectively. In contrast, the CO2 footprint would be increased by 5% if offsite fabricated materials were used in facades, slabs, and partition walls.

PurposeAs part of a study that aimed at enhancing the future roles and functions of building services (BS) engineers in Hong Kong, a survey was carried out to obtain demographic information about BS practitioners as well as their views and opinions on a range of issues which affect professional practices of BS engineers and recognition of their contributions by others. The purpose of this paper is to give a portrait of BS engineers in Hong Kong.Design/methodology/approachA series of statistical analyses were conducted based on the responses given by the BS practitioners, which included their qualifications, experience, job field, annual income and the number of trades of BS systems that they are competent in and responsible for.FindingsThe statistics show that: competence gap exists in that BS engineers are required to handle more trades of BS systems than those they are competent in; and the academic and professional qualifications, years of experience and job position are the key influential factors to the annual income of BS engineers but little differences exist in the average annual income of engineers in different job fields.Originality/valueThe competence gap is a concern that needs to be addressed to ensure BS engineers are competent in handling the common trades of BS systems, which is increasingly important for them to perform effectively in integrated professional teams for turning out holistic solutions for sustainable building developments.

This study applied the Monte Carlo method to generate probabilistic distributions for describing the CO 2 footprint of the superstructure of a high-rise concrete office building. The distribution profile was constructed with the material use data collected from thirteen high-rise office concrete buildings in Hong Kong. Our results indicate that the superstructure of an office building (i.e. it does not embrace foundation or basement), on average, had a footprint of 215.1 kg CO 2 /m 2 . External walls and upper floor construction had the highest CO 2 footprint, followed by suspended ceilings and finishes. These three elements altogether accounted for an average of 84.2% of the CO 2 footprint associated with the superstructure. Furthermore, this study also evaluated the emissions reduction impacts of five different material use options over a 60-year lifespan. Among all the studied options, the most effective option is to maintain 15–30% of the existing structural and non-structural building elements as it can reduce the CO 2 footprint by 17.3%. Diverting construction wastes to recycling can reduce the CO 2 footprint by 5.9%. Reusing resources and importing regional materials can each only reduce the CO 2 footprint by 3.2% and 3.1% respectively. In contrast, the CO 2 footprint will be increased by 5% if off-site fabricated materials are used in facades, slabs and partition walls.

Noise annoyance has caused significant adverse impacts on human beings and numerous efforts have been spent on mitigating annoyance problems. Natural greenery has been shown to be able to moderate annoyance problems at home but this conclusion was drawn without properly controlling the potential confounding factors. Furthermore, few have explored the moderation effect of a sea view. Accordingly, this study formulated a multivariate model to examine the impacts of natural views as well as personal characteristics on annoyance perception. A housing estate was selected in Hong Kong as the survey site for which some of the residents were exposed to greenery views, sea views, or both from their homes. Eight hundred and sixty-one responses were collected via questionnaire surveys and analyzed using an ordered logit model. The results suggest that both a greenery view and a sea view can moderate annoyance responses. Several individual's personal characteristics are found to affect individuals' annoyance perception. The duration of time spent daily at home is shown to have an influence on the moderation impact exerted by a greenery view, while the age of an individual is shown to have an influence on noise moderation effect exerted by a sea view.

PurposeThe purpose of this paper is to narrow the diverse views of the industry stakeholders on two controversial issues, namely the scope of core competence of building services engineers (BSEs) and the statutory role that they should play, which were encountered in an extensive research study on the building services profession of Hong Kong.Design/methodology/approachAn expert panel was formed and the Delphi method was applied to resolve the controversies. In the Delphi process, every panel member was provided with complete opinions expressed by all other panel members in each round of the deliberation.FindingsSufficient support was found for the proposition that professional BSEs should be competent in handling air‐conditioning, electrical, fire services, and plumbing & drainage works, and that the government authorities should mandate the design and compliance certification of electrical and fire services installations by BSEs.Research limitations/implicationsAlthough the Delphi method has not been hitherto applied to resolve the controversies addressed in the study, it was proven to be a very effective tool in seeking majority opinions from a group of experts. The same approach may be taken in similar studies in future.Practical implicationsThe core competence identified should be made as a minimum requirement for practitioners who wish to practise as professional BSEs. The views and comments given by the expert panel members are informative references to public policy makers.Originality/valueThis was the first ever study conducted in an attempt to identify the core competence and statutory role of BSEs in Hong Kong.

Eighty-five measurement campaigns were performed repeatedly to compare the concentration variation profiles along two intra-urban roads-one with open configuration and the other with street canyon effect. Fixed-effects panel data analysis was applied for formulating a model to express the PM(10) concentrations along intra-urban roads in terms of parameters like nearby central monitoring data, traffic counts and meteorological conditions with an objective to analyze the PM(10) concentration variation patterns along the two roads. Our findings reveal that traffic intensity and metrological conditions exert influence on concentration variation for both types of road configurations while wind velocity only affect the pollutants removal effectiveness of open road configuration. Further analysis unveils that the PM(10) concentration distribution profiles within a compact city environment are not always uniform and are dependent on the road configuration. Considerable PM(10) concentration differences were observed along the street canyon, and 70% of their variations are attributed to variations in their road aspect ratios. By contrast, no significant concentration difference is observed at open road configurations.

PurposeA specification can be an effective contractual tool to help achieve green construction. In Hong Kong, a multifarious specification arrangement exists in the construction industry, despite progress being made in the public and private organizations towards green practice. The purpose of this paper is to propose a green specification framework by modeling after established green specification systems.Design/methodology/approachThree sample work sections of green specification have been prepared for concrete, paint and lighting to represent structural, architectural and building services trades, with which a series of interviews with construction stakeholders was conducted. Assisted by a structured questionnaire, the time, cost, quality and liability implications of the proposed framework were studied.FindingsApart from minor additional cost, time and liability impacts, which would level off with increasing use of green products and practice, the quality of construction is perceived to be good if the framework is adopted.Originality/valueThe proposed framework embraces the important facets for specifying green construction. A roadmap is also recommended for its sustainable adoption. The methodology and results will be of good reference value for other jurisdictions.

As the number and complexities of green building developments are mainly driven by market demands, understanding of end-user behaviors towards their development eventually should play a crucial role on determining their successes. However, very few studies have been attempted to explore end-user behaviors towards green building development. This study successfully applied discrete choice experiments to reveal whether residents with green experience will have different preference and willingness-to-pay values for enhancements on various aspects of environmental performance in green buildings. Generally, both green and conventional residents had strong preferences and were willing to pay more for improving various aspects of environmental performance in green residential developments. They are found to be willing to pay more for energy conservation, than indoor air quality improvement, noise level reduction, landscape area enlargement, or water conservation. No significant differences are found in the preferences between green and conventional residents for energy conservation, indoor air quality improvement, indoor noise reduction, or water conservation, However, green residents were found to be willing to pay significantly less than the conventional residents for enlarging the landscape area within a residential development, despite it was perceived by green residents as one of the major elements that differentiate a green from a conventional development.

PurposeThe survey reported here is intended to obtain an understanding of the general public's perception about building services and building services practitioners in Hong Kong.Design/methodology/approachTargeting a sampling error of within ±1 per cent at a confidence level of 95 per cent, a team of six surveyors conducted face‐to‐face interviews with 751 laypersons at places around 11 residential estates.FindingsOver 90 per cent of the general public know the presence of various building services installations in buildings and 12 per cent know that building services is the collective name of such installations. The general public are satisfied with the operability and reliability of building services installations but are just marginally satisfied with their performance at higher levels, such as energy conservation and indoor air quality control.Research limitations/implicationsA paucity of teenagers know about building services, which is a concern to the future development of both the building services profession and the facilities management (FM) industry in Hong Kong. Future work may investigate the situation in other regimes with a similar FM setting and study on how the profession is perceived for buildings with restricted access to the general public. Operation and maintenance personnel of the FM offices, who are approached by most people when problems with building services installations arise, are the key on the perceived image of building services professionals.Originality/valueIn addition to informing higher educational institutes the need to reinforcing promotion of building services engineering to school leavers, the findings can help professional institutions in formulating how the social status of building services engineers may be raised.

The use of green specifications as a contractual tool to promote sustainable development should be adopted in the construction industry. The definition and characteristics of green specifications are presented in conjunction with the results of a cross-sectional survey on the possible barriers to their implementation. Generally, construction stakeholders agree that environmental considerations should be included in construction specifications but their underlying motive may be simply for satisfying mandatory requirements. Among the potential barriers identified, the additional cost associated with green requirements is perceived to be the most dominant barrier, followed by possible delay and a limited pool of competent suppliers. Although the crucial barriers based on overall responses were identified, different groups of stakeholders have shown their concerns on particular barriers. Hence, their concerns should be addressed with due regard to these differences during implementation of green specification...

This study estimates the willingness-to-pay value for a one dB(A) change over a range of initial noise levels for a sample population in Hong Kong. It establishes a protocol for estimating the willingness-to-pay values by first establishing an annoyance–dB relationship. The protocol takes into account the characteristics that the probability of being annoyed at a particular level varied with the initial objective noise level, and the annoyance–dB relationship varied for a range of initial annoyance level. The study shows that household income level and initial annoyance levels exert considerable influences on the individual’s willingness-to-pay values. However, age and educational level were found not to exert any significant influence on individual’s willingness-to-pay values.

The cosorption characteristics of water and toluene vapors in various concentrations of triethylene glycol (TEG) solution flowing through a packed-bed dehumidifier are investigated in this paper. A multi-component model was constructed using the reported equilibrium relationships of toluene and water vapors in TEG solutions together with the Krishna-Standart multi-component mass transfer correlation. The effects of liquid-to-air ratios, TEG inlet temperatures, air inlet temperatures were reported on the moisture and toluene removal rate as well as the moisture and toluene removal efficiency of the packed dehumidifier. Running the packed dehumidifier in a higher liquid-to-gas flow ratio generally increased the removal rates and efficiencies of both water vapor and toluene vapor from the airstream. Increasing inlet temperatures of the TEG solution led to a decrease in the removal rate of water vapor when running the packed dehumidifier at a high liquid-to-gas flow ratio. However, there was no significant ch...

The growing concerns over the environmental impacts of buildings have led to increasing demands for more environmental friendly buildings and building materials. Hitherto, there are not any comprehensive studies that show the overall environmental impact profiles of building materials and building services components for buildings. This paper intends to bridge this gap by reporting overall lifecycle environmental profiles of buildings as well as the ranking orders of environmental impacts of all the building materials and building services materials and components for commercial buildings. Twenty-five commercial buildings in Hong Kong, which include three Grade A office buildings, four Grade B office buildings, one Grade C office buildings, four retail centers and three hotels, have been selected for our study. Based upon these collected samples, no statistical differences were found in the average lifecycle environmental impacts for different building types despite some minor variations were detected. Subsequently, 10 types of building materials and 10 types of building services components have been identified for their significant lifecycle environmental impacts on commercial buildings. Among all, concrete, reinforcement bar, copper power cables, and copper busbars were ranked to be the four most significant materials or components to the total lifecycle environmental impacts. These should form the major targets for improvements in environmental performance of commercial buildings.

The relationship between house price and location is very complicated. Traditional theory mainly emphasizes the relationship between the effects of accessibility to central locations on housing prices and ignores location-specific attributes of housing. Previous studies at best examine only one or a few environmental amenities. However, little has been done on a high-rise, densely populated living environment. This paper thus aims to investigate the “neighboring and environmental characteristics” of a residential property on its market value in such unique setting. It uses a more advanced approach—i.e. a hedonic model with spatial adjustments—and applies GIS techniques. The findings are mostly consistent with our hypotheses. The traveling time from the apartment to the central business district is negatively correlated with housing price. Households are also willing to pay more for apartments with sea view and better air. However, greenbelt is not a significant variable on housing price and noise level is even found to be positively correlated with the price. This unexpected finding may be explained by the uniquely dense living environment in Hong Kong where households are willing to sacrifice serenity for convenience. The current research is adequately sophisticated and has contributed to a better understanding of the important theoretical question of how much a household is willing to spend on various environmental and neighbourhood attributes of an apartment.

This study investigates the relationship between the residence and the relative importance of different environmental attributes by focusing on a sample of residents in Hong Kong. Both discrete choice analysis and Likert-scale rating were employed to reveal the importance and the hierarchical order of importance being used by the residents in their evaluation of six environmental attributes. Our results generally showed that the residents actually evaluated the environmental attributes as what they perceived. Our analysis revealed that neither the environmental quality of neighborhood area nor the housing estate design exerted significant influence on the hierarchical order of importance considered by the residents. It was found that the nature of environmental attributes exerted a significant impact. The residents were generally found to have placed greater importance on those environmental attributes that would pose a threat to themselves rather than to the environment. Also, the residents were shown to consider those environmental attributes that would threaten their personal health to be more important than those would threaten their comfort. The long-term significance of this study is to enhance the understanding of different environmental attributes associated with the housing estates. This enhanced understanding should help inform the decision making process on prioritizing the implementation of environmental strategies within a housing estate when confronted with a limited budget.

This study examines the relative importance of environmental attributes and sensation of outdoor connection in the design of windows for a workplace by focusing on a sample of practicing building d...

This study examines the amount of money that designers and developers are willing to pay to improve different aspects of the environmental performance of exterior envelopes by using office buildings in Hong Kong as an example. A method modified from the averting expenditure approach was applied to 16 office buildings built or tendered between 1999 and 2001. Our results show that the designers and developers considered the provision of an appropriate sensation index of outdoor connection (or window to wall ratio) for building envelopes was far more important than improvement of the environmental performance when the interiors of their buildings were open to a view showing them surrounded by other office buildings. Improvement in thermal performance of building envelopes would be considered only if an appropriate window-to-wall ratio had been fixed. Application of the method has successfully shown the amount an individual developer will invest and a designer’s willingness to pay to improve the performance of a building envelope. The methodology should be able to be extended to other building elements, components or systems after some modifications.

This paper reports a pioneering and quantitative approach being developed for assisting a large-scale high-rise residential building developer in Hong Kong in monitoring the competitiveness in the supply of fresh and flush water pumps to the building development projects. Integrated empirical pricing models based upon the hedonic price technique have been developed for the supply of both fresh and flush water pumps to the developer and the competitive sector. Our results revealed that the pricing levels charged to the developer were comparable to the competitive sector even though the quality standards of water pumps delivered were much lower. Upon close examination of the market structure, it was found that this was possibly due to the Limit Pricing Strategy being adopted by two leading suppliers in the developer's market as a result of relaxing the pre-qualification to standards below the industry norm. This finding should add to our understanding on the impact on the market competitiveness due to relaxation of pre-qualification requirements. Besides, measures of enhancing competitiveness in the supply market have also been discussed.

Much is written nowadays about ‘green buildings’, although clear concepts and descriptions are generally absent from the discussion. Building environmental assessment methods (BEAMs) have been developed to give a rating that provides a more holistic assessment of building performance. To appreciate the outcome of an assessment, ie what a building ecolabel signifies in terms of environmental performance, it is necessary to take full account of the environmental aspects that are assessed, the standards of performance required, the relative weightings of each aspect, and the overall score required to achieve a specified grade. Based on a review of several well-established BEAMs this paper seeks to help the reader weigh up the relative ‘greenness’ of a particular building eco-label.

A voluntary indoor air quality certification scheme has been proposed in Hong Kong for assessing and evaluating the indoor air quality level in a variety of public places like offices, restaurants and pubs. The scheme intends to promote the public well being, however, its technical and financial practicality has led to serious discussions among the government officials, practitioners and premises owners. Accordingly, this study intends to develop a protocol for examining its financial viability by linking the appropriate dose-response and economic data with the results from indoor micro-environment models. The financial viability of the scheme is evaluated by examining the cost and benefit associated with compliance on the different prescribed indoor particulate (PM10) levels. According to our analysis, the indoor action level of 180 microg/m3 as 8-h mean (with the objective of protecting the health of general public) does not require office owners to improve beyond the base setting. Nevertheless, owners should consider altering the base settings in their air conditioning systems so as to secure more benefit on every dollar they spent. On the contrary, the 20 microg/m3 level as 8-h mean (with the objective of providing comfort) is not considered to be financially viable for office owners as they will incur financial loss on compliance. Subsequent sensitivity analysis indicates that the total net benefit derived have a great dependency on the value-of-life estimates used. If conservative health estimates are adopted, the optimum level determined to be beneficial to both owners and the society will be 55 microg/m3, which can be obtained by operating the air conditioning system with a ventilation rate of 10 l/s, primary filters of 80-85% efficiency and secondary filters efficiency of 60-65% arrestance. This information should be extremely valuable for government officials and policy makers in assessing the financial viability of the voluntary indoor assessment scheme.

This paper reports an innovative, scientific and yet practicable approach developed in assisting a large-scale high-rise residential building developer in Hong Kong for monitoring the competitiveness in the switchboard supply to her development projects. In this study, a pricing indicator was developed for monitoring whether the pricing levels charged to developer had attained a competitive level. Our results revealed that the pricing level charged to the developed was far from competitive, and the high cost was contributed by inadequate competitiveness in the switchboard supply as a result of the practice of including only a limited number of suppliers on the pre-qualification list. By relaxing the pre-qualification requirements, the pricing level dropped to a very competitive level after two additional suppliers being included on the list.

The growing importance of the maintenance industry renews the interest of both practioners and academia working in the maintenance field. In the past or even now, most of the maintenance work contractors are selected purely on basis of the lowest tender prices, even though they are required to be undergone the pre-qualification process. However, it is increasingly admitted that the practice of awarding tenders on a basis of low tender price eventually would lead to the ultimate quality problems. In consequence, there is a serious outcry in the public sector demanding a revolution in the current tender awarding system. Accordingly, this study intends to test how different managers actually choose maintenance contractors. This in turn would lead us to focus on the identification of the major selection attributes, and the trade-off weightings among attributes during the selection process. In this study, the identification and the trade-off weightings for different contractors selection attributes are revealed by conjoint analysis. Meanwhile, a Likert scale rating is also used to reveal whether there are disparities between the relative perceived importance and the relative weights in actual selection in the contractors selection attributes. Our results found that there are some consistencies in the relative perceived importance and the relative weights in actual contractor selection. On the other hand, our results also reveal that the contractors should put more effort in improving their company reputation in order to win the maintenance contracts.