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The purpose of this paper is to adduce the most appropriate thermal comfort assessment method for determining human thermal comfort and energy efficient temperature control in office buildings in tropical West Africa.

This paper examines the Adaptive Thermal Comfort Standard, from its research evolution to its contemporary use as an environmental design assessment Standard. It compares the adaptive component of ASHRAE Standard 55 and the European CEN/EN 15251. It begins by reviewing relevant literature and then produces a comparative analysis of the two standards, before suggesting the most appropriate Adaptive Thermal Comfort Standard for use in assessing conditions in tropical climate conditions. The suggested Standard was then used to analyse data collected from the author's pilot research into thermal conditions, in five office buildings situated in the city of Enugu, South Eastern Nigeria.

The paper provides insight as to why the ASHRAE adaptive model is more suitable for thermal comfort assessment of office buildings in the tropical West African climate. This was demonstrated by using the ASHRAE Thermal Comfort Standard to assess comfort conditions from pilot research study data collected on Nigerian office buildings by the author.

The paper compares the adaptive component of ASHRAE Standard 55 with CEN/EN 15251, and their different benefits for use in tropical climates. It suggested the need for further research studies and application of the ASHRAE Adaptive Thermal Comfort Standard in the tropical West African climate.

This study has covered many types of solar-powered air-conditioning systems that may be used as an alternative to traditional electrically powered air-conditioning systems in order to reduce energy usage. Solar adsorption air cooling is a great alternative to traditional vapor compression air-conditioning. Solar adsorption has several advantages over traditional vapor-compression systems, including being a green cooling technology which uses solar energy to drive the cycle, using pure water as an eco-friendly HFC-free refrigerant, and being mechanically simple with only the magnetic valves as moving parts. Several advancements and breakthroughs have been developed in the area of solar adsorption air-conditioners during the previous decade. However, further study is required before this technology can be put into practise. As a result, this book chapter highlights current research that adds to the understanding of solar adsorption air-conditioning technologies, with a focus on practical research. These systems have the potential to become the next iteration of air-conditioning systems, with the benefit of lowering energy usage while using plentiful solar energy supplies to supply the cooling demand.

The aim of this paper is to present a parametric design method to generate optimum adaptive facades regarding occupants' comfort and building energy criteria. According to the literature review, the following questions have arisen to address the research gaps: Is it possible to have the outside view throughout the whole year without discomfort glare by utilising adaptive solar facades (ASFs)? How can architects integrate both view quality and quantity into ASF design? What is the impact of dynamic vertical shading systems mounted on south facades on the outside view, occupants' visual comfort and operational energy? How can we evaluate the view quantity through multi-layer shading systems?

In recent years, there is a surge in demand for fully glazed buildings, motivating both architects and scholars to explore novel ideas for designing adaptive solar facades. Nevertheless, the view performance of such systems has not been fully explored especially when it comes to the effect of dynamic vertical shading systems mounted on south facades. This fact clarifies the need to conduct more research in this field by taking into account the window view and natural light. Consequently, a simulation research is carried out to investigate the impact of a dynamic shading system with three vertical slats used on the south facade of a single office room located in Tehran, on both view quality and quantity, visual comfort and operational energy. The research attempts to reach a balance between the occupant's requirements and building energy criteria through a multi-objective optimisation. The distinctive feature of the proposed method is generating some optimum shading which could only cover the essential parts of the window area. It was detected from the simulation results that the usage of a dynamic vertical shading system with multi slats for south facades compared to common Venetian blinds can firstly, provide four times more view quantity. Secondly, the view quality is significantly improved through enabling occupants to enjoy the sky layer the entire year. Finally, twice more operational energy can be saved while more natural light can enter the indoor environment without glare. The final outcome of this research contributes toward designing high-performance adaptive solar facades.

This paper proposes a new metric to evaluate the view quantity through a multi-layer shading system. The proposed method makes it clear that the usage of dynamic vertical shading systems with multi-layers mounted on south facades can bring many benefits to both occupants and building energy criteria. The proposed method could (1) provide four times more view quantity; (2) improve view quality by enabling occupants to watch the sky layer throughout the whole year; (3) slash the operational energy by twice; (4) keep the daylight glare probability (DGP) value in the imperceptible range.

The research limitations that should be acknowledged are ignoring the impact of the adjacent building on sunlight reflection, which could cause discomfort glare issues. Another point regarding the limitations of the proposed optimisation method is the impact of vertical shading systems on users' visual interests. A field study ought to be conducted to determine which one could provide the more desirable outside view: a vertical or horizontal the view. Research on the view performance of ASFs, especially their impact on the quality of view, is sorely lacking.

This paper (1) analyses the performance of dynamic vertical shadings on south facades; (2) evaluates outside view through multi-layer shading systems; and (3) integrates both view quality and quantity into designing adaptive solar facades.

This study aims to evaluate the effect of the installed photovoltaic (PV) systems on the aesthetic perception of the mosque’s architectural form. It also aims to develop a framework for integrating PV cells with the various elements of the building type.

The study adopted a mixed-method approach comprising both qualitative and quantitative techniques for data collection procedures. This includes surveys, literature review, focus groups and an experiment.

The results revealed a negative impact of the building-applied PV panels on people’s perception of the mosque’s architectural form. However, integrating the PV cells with the mosque form was perceived as more aesthetically pleasing. Certain integrating PV strategies integrated more harmoniously with certain mosque styles.

This study is focused on limited styles of one building type. Extra research is needed to explore the differences between the different participated groups.

There is a lack of research that explores the ways the installed PV systems impact the users’ architectural aesthetic perception of the mosque. This study informs the design process and practice and construction industry by highlighting the opportunities PV systems, as a legitimate sustainable energy resource, offers to architects and manufacturers.

As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation.

Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices.

Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient.

This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions.

This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment.

There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey.

Understanding the thermal performance of sandcrete hollow block walls in the tropic is very essential for occupants' well-being, productivity and efficiency, due to its widespread application in buildings in the study area. Lokoja, in Nigeria, lies in the warm humid zone with its attendant's high temperatures all year round. Thus, providing an acceptable walling material that will control the high indoor air temperature becomes imperative. This paper assessed sandcrete hollow blocks as a walling material used in Lokoja, to determine the thermal performances for effective thermal comfort of the residents.

It involves the construction of a habitable model building with the commonly available sandcrete hollow blocks in the area. One unit of Cryopak iMINI Temperature and Relative Humidity Data Logger called new generation intelligent iMINI with Serial Number and Product Code MX-CI-145–0009 and MX-HE-S-16-L was installed, to record the indoor air temperature and relative humidity data at an interval of one hour, for 12 months covering dry and wet seasons. The results of the recorded data were downloaded to an excel spread sheet for assessment and analysis throughout the seasons. The values were computed using the temperature–humidity index (THI) equation, with a view to determine the indoor thermal comfort level category.

The study revealed that sandcrete hollow block walls provide thermal discomfort of the indoor environment for both seasons, with attendant adverse effects in the comfort of the occupants. The paper concludes that proper orientation of buildings, planting of trees, use of low absorbing or reflective surface materials, application of cavity walls to receive insulation materials in between the hollow spaces provided, instead of the single walling as well as providing shading device elements, can improve users' comfort and also ameliorate the heat effect on the external surface of building transferred into the interior by conduction, radiation or convection within the area and in the tropics at large. Other thermally eco-friendly wall materials available in Lokoja includes timber, stabilized laterite–cement blocks, burnt bricks and earth-mud bricks which can be used to replace sandcrete hollow block walls. These alternative wall materials are used for construction of residential and office buildings by the colonial government of Sir Fredrick Lugard in the study area.

The application of sandcrete hollow blocks as a wall material is in vogue, not minding its thermal discomfort to the users and the environment; this is due to its availability and ease of production. The acceptability of this walling material requires holistic study to unravel the best way to reduce the thermal discomfort inherent in its application.

The author succeeded in revealing the thermal performance of sandcrete hollow blocks as walling material in Lokoja, the study area. It is a first attempt at understanding the performance for human comfort in the area. This will greatly assist the resident and other researchers to improve on the application of sandcrete hollow blocks as walling material towards ensuring that maximum indoor thermal comfort is achieved.

To establish national energy performance benchmarks and an energy efficiency classification system for commercial office buildings from whole building to sub‐systems level for building professionals including facility managers.

Issuing of survey form and questionnaires to 16 building owners before field interview. Building physical data and systems nameplate, quantities and types were verified on site. The past 24 months electricity consumption bills were also collected from building owners. Physical environmental conditions and short‐term power measurement on building systems were done to determine the level of energy consumption and performance.

The classification and benchmarking methodology developed is useful for the regions to establish their own database and tools.

The building energy performance assessment and auditing methodology are useful to both building owner/manager and energy services companies (ESCOs) in carrying out systematic assessment and analysis on building energy characteristics. The benchmark system established will also serve as a reference to building professionals to adopt a more holistic approach in designing an energy efficient building. Useful also for building owners who are considering carrying out retrofitting works on their existing building or systems.

The study provides detailed whole building and systems benchmarks for Singapore. The results provide an objective evaluation system of commercial office building energy performance.

Application of appropriate shading device strategies in buildings can reduce direct solar heat gain through windows as well as optimize cooling and artificial lighting load. This study investigates the impact of common shading devices such as overhangs, fins, horizontal blinds, vertical blinds and drapes on energy consumption of an office building and suggests energy efficient shading device strategies in the contexts of unique Bangladeshi subtropical monsoon climate.

This research was performed through the energy simulation perspective of a prototype office building using a validated building energy simulation tool eQUEST. Around 100 simulation patterns were created considering various types of shading devices and building orientations. The simulation results were analysed comprehensively to find out energy-efficient shading device strategies.

Optimum overhang and fin height is equal to half of the window height in the context of the subtropical climate of Bangladesh. South and West are the most vulnerable orientations, and application of shading devices on these two orientations shows the highest reduction of cooling load and the lowest increment of lighting load. An existing building was able to save approximately 7.05% annual energy consumption by applying the shading device strategies that were suggested by this study.

The shading device strategies of this study can be incorporated into the Bangladesh National Building Code (BNBC) as new energy-efficient building design strategies because the BNBC does not have any codes or regulations regarding energy-efficient shading device. It can also be used as energy-efficient shading device strategies to other Southeast Asian countries with similar climatic contexts of Bangladesh.

The purpose of this paper is to focus on the ongoing discourse centred on enhancing building performance to provide an interpretation of life cycle cost (LCC) analysis, directly applicable to building construction in coastal areas located in tropical wet–humid settings.

A survey of 50 buildings based on physical observation is carried out to identify typical failure patterns in wet‒humid environment. Further, a comparative initial construction cost and LCC analysis is computed for two alternative building schemes with identical floor plans: Scheme A using sound construction and detailing to guard against future maintenance problems and Scheme B adopting the typical designs evident in the study area.

The result of the analysis shows that in the long-run scheme, A is an economically more viable option than B, as the increased initial costs are entirely offset by the reduced running cost.

The contextual nature of LCC analysis poses difficulties in applying the evidence provided in this study to provide a generalisable financial justification to buildings clients.

The outcome of the study provides analytical validation to overcome resistances and enables informed decision making by clients, which is necessary to promote transition from conventional to environmentally responsive design choices suitable to wet–humid conditions.

The study provides an interpretation of LCC analysis, directly applicable to building construction in the tropical wet–humid setting of coastal areas against the backdrop of inconsistencies in the practical application of the theory of LCC.