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The world is facing a rapid increase of air conditioning of buildings. It is the motivation of Annex 80 to develop, assess and communicate solutions of resilient cooling and overheating protection. Resilient Cooling is used to denote low energy and low carbon cooling solutions that strengthen the ability of individuals and our community to withstand, and prevent, thermal and other impacts of changes in global and local climates. It encompasses the assessment and Research & Development of both active and passive cooling technologies of the following four groups: Reduce heat loads to people and indoor environments.Remove sensible heat from indoor environments.Enhance personal comfort apart from space cooling.Remove latent heat from indoor environments.The present review sums up the state of the art in cooling solutions which may be regarded as resilient. Its main objective is to systematically describe the available cooling solutions, their physical basis, their benefits and limitations, their technology readiness level, their practical availability, and applicability. Doing so, the State-of-the-Art Review forms the basis for the work of Annex 80.

The world is facing a rapid increase of air conditioning of buildings. This is driven by multiple factors, such as urbanization and densification, climate change and elevated comfort expectations together with economic growth in hot and densely populated regions of the world. The trend towards cooling seems inexorable therefore it is mandatory to guide this development towards sustainable solutions. Against this background, it is the motivation of Annex 80 to develop, assess and communicate solutions of resilient cooling and overheating protection. Resilient Cooling is used to denote low energy and low carbon cooling solutions that strengthen the ability of individuals and our community as a whole to withstand, and also prevent, thermal and other impacts of changes in global and local climates. It encompasses the assessment and Research & Development of both active and passive cooling technologies of the following four groups: - Reduce heat loads to people and indoor environments. - Remove sensible heat from indoor environments. - Enhance personal comfort apart from space cooling. - Remove latent heat from indoor environments. The Annex 80’s main objective is to support a rapid transition to an environment where resilient low energy and low carbon cooling systems are the mainstream and preferred solutions for cooling and overheating issues in buildings

Urban built form and density are crucial parameters for the optimization of building energy performance. However, a cohesive framework which correlates building energy with urban built form and density is lacking, with no unified agreement on the concept of urban density. This study establishes the subtle interrelationships between urban built forms, density and building energy performance using two density indicators, specifically, site coverage and plot ratio. This paper initially considers geometrical variables of four customary urban built forms to investigate their relationship with the density indicators. Energy analyses are performed on the geometrical models representing residential buildings using the City of London as an example of a temperate climate. Annual building energy demands of pavilion, terrace, court and tunnel-court forms are calculated. The findings are used to produce a heat map of energy intensity on the Form Signature graphs. Results show that high-rise buildings with greater plan depths achieve higher energy efficiency. Moreover, it is shown that greater cut-off angles correspond to higher energy demands under temperate climatic conditions. An energy indicator, termed Energy Equity is introduced which represents the ratio between PV energy generation installed on roofs with respect to the total energy demand of the building. Further analyses show that by considering energy demand and PV energy generation simultaneously, low-rise buildings with greater plan depths provide improved energy performance. A comparative analysis of the energy performance of different built forms with similar geometric parameters demonstrates that the tunnel-court and the pavilion built forms provide the best and worst energy performance, respectively. However, when constraining density whilst changing other geometric parameters, this converse is true. Finally, the study illustrates that the same density for the same built form can be achieved by different combinat

The rising profile of carbon footprinting in building lifecycle has caught the attention of many in the construction industry and academic circles. There is an increasing awareness of the effectiveness of an holistic approach by calculating the entire impact of the building by considering all stages of whole life carbon emissions including the initial, annually repeating and end of life impacts as this gives a better representation of the scale of the impact compared with focusing on savings achieved by adopting a specific elemental choice. It is now widely realized that we are living on a planet with finite resources and that we should make every effort to reduce our ecological footprint. Within the construction industry, it is now accepted that tackling environmental sustainability alone is not sufficient and that we have to adopt a holistic approach by addressing the other two aspects of sustainability namely social and environmental. To reduce its huge impact, accounting for almost half of the global greenhouse gases and consumption of the materials entering the global market, the industry has succeeded in developing new and innovative solutions. These include the reintroduction of traditional construction techniques, refurbishment and conversion against new built, renewables and similar initiatives. This paper investigates savings in the carbon emissions of refurbishing buildings compared against a new build scenario. Whole life emissions calculations have been carried out to analyse the total environmental impact including embodied and operational stages of building life cycle. The paper also highlights the results of the survey carried out to analyse the building in-use dimensions for environmental quality of the newly refurbished office building.

The building and transportation sectors are responsible for the greatest proportion of energy consumption in cities. While they are intrinsically interlinked with urban built form and density, climate change and technological innovation are having an effect on their relative contributions. This paper aims to develop an optimisation framework to facilitate the identification of the most energy-efficient urban built forms and urban geometry for the future built environment that can be adapted to the changing climate and ongoing technological development. It examines future scenarios for the city of London as a temperate climate zone (as a case study), in 2050, and contrasts it with the present situation. Specifically, the impact of climate change along with the penetration of electric vehicles into the transportation system that can be charged via rooftop photovoltaics is investigated. This study initially develops the geometrical models of four selected urban built forms and, secondly, analyzes their energy performance using an urban energy simulation software. The results, showing the impact of future scenarios on building energy performance, urban built form and density, demonstrate that court and tunnel-court built forms show better energy performance for future development. It is therefore recommended that for future urban developments in London, deep plan court and tunnel-court buildings with a lower number of storeys and a large cut-off angle are more advantageous in terms of building energy to accommodate the expected climate change. Finally, results of simulation trials indicate that the total building energy demand in 2050 is considerably higher than in the present climate as a result of additional cooling load and electric vehicle charging load.

Urban built form and density are crucial parameters for the optimization of building energy performance. However, a cohesive framework which correlates building energy with urban built form and density is lacking, with no unified agreement on the concept of urban density. This study establishes the subtle interrelationships between urban built forms, density and building energy performance using two density indicators, specifically, site coverage and plot ratio. This paper initially considers geometrical variables of four customary urban built forms to investigate their relationship with the density indicators. Energy analyses are performed on the geometrical models representing residential buildings using the City of London as an example of a temperate climate. Annual building energy demands of pavilion, terrace, court and tunnel-court forms are calculated. The findings are used to produce a heat map of energy intensity on the Form Signature graphs. Results show that high-rise buildings with greater plan depths achieve higher energy efficiency. Moreover, it is shown that greater cut-off angles correspond to higher energy demands under temperate climatic conditions. An energy indicator, termed Energy Equity is introduced which represents the ratio between PV energy generation installed on roofs with respect to the total energy demand of the building. Further analyses show that by considering energy demand and PV energy generation simultaneously, low-rise buildings with greater plan depths provide improved energy performance. A comparative analysis of the energy performance of different built forms with similar geometric parameters demonstrates that the tunnel-court and the pavilion built forms provide the best and worst energy performance, respectively. However, when constraining density whilst changing other geometric parameters, this converse is true. Finally, the study illustrates that the same density for the same built form can be achieved by different combinat

The rising profile of carbon footprinting in building lifecycle has caught the attention of many in the construction industry and academic circles. There is an increasing awareness of the effectiveness of an holistic approach by calculating the entire impact of the building by considering all stages of whole life carbon emissions including the initial, annually repeating and end of life impacts as this gives a better representation of the scale of the impact compared with focusing on savings achieved by adopting a specific elemental choice. It is now widely realized that we are living on a planet with finite resources and that we should make every effort to reduce our ecological footprint. Within the construction industry, it is now accepted that tackling environmental sustainability alone is not sufficient and that we have to adopt a holistic approach by addressing the other two aspects of sustainability namely social and environmental. To reduce its huge impact, accounting for almost half of the global greenhouse gases and consumption of the materials entering the global market, the industry has succeeded in developing new and innovative solutions. These include the reintroduction of traditional construction techniques, refurbishment and conversion against new built, renewables and similar initiatives. This paper investigates savings in the carbon emissions of refurbishing buildings compared against a new build scenario. Whole life emissions calculations have been carried out to analyse the total environmental impact including embodied and operational stages of building life cycle. The paper also highlights the results of the survey carried out to analyse the building in-use dimensions for environmental quality of the newly refurbished office building.

The global effects of climate change will increase the frequency and intensity of extreme events such as heatwaves and power outages, which have consequences for buildings and their cooling systems. Buildings and their cooling systems should be designed and operated to be resilient under such events to protect occupants from potentially dangerous indoor thermal conditions. This study performed a critical review on the state-of-the-art of cooling strategies, with special attention to their performance under heatwaves and power outages. We proposed a definition of resilient cooling and described four criteria for resilience—absorptive capacity, adaptive capacity, restorative capacity, and recovery speed —and used them to qualitatively evaluate the resilience of each strategy. The literature review and qualitative analyses show that to attain resilient cooling, the four resilience criteria should be considered in the design phase of a building or during the planning of retrofits. The building and relevant cooling system characteristics should be considered simultaneously to withstand extreme events. A combination of strategies with different resilience capacities, such as a passive envelope strategy coupled with a low-energy space-cooling solution, may be needed to obtain resilient cooling. Finally, a further direction for a quantitative assessment approach has been pointed out.

The Palestinian energy sector faces several challenges which are: the energy insecurity, the high fuel prices, the increase in demand and the absence of sustainable consumption. Despite that the energy consumption per capita in Palestine is one of the lowest in the region, energy efficiency can have positive impact on the living conditions of the Palestinian households and increase the resilience of the community. Benchmarking tools for quantifying the energy consumption and defining the impact of efficiency measurements can play a main role in increasing the collective awareness of households towards sustainable consumption of energy. The research focuses on heating and cooling (HC) energy consumed in the domestic sector. A multimode survey was used to collect physical characteristics of the building, the socioeconomic characteristics and the thermal behaviour of the households. Data was collected from 320 households in Hebron. Regression models were developed as benchmarking tools for estimating the heating and cooling energy consumption. A regression model to estimate the cooling energy using fans is presented in this paper as a sample of these tools.

Designers usually assume several parameters when building simulation models. Among these assumptions is the preferred indoor climatic conditions. However, thermal comfort is a subjective matter in which people perceive differently. The discrepancy between the assumed and preferred indoor conditions can cause the “comfort gap” which contribute to the performance gap. In this paper, personalized thermal sensation vote equations were developed for seven respondents. They were developed based on coupling monitoring with “right here right now” survey to define the preferred indoor temperature for each of them. Adapting this approach, especially using an automated system is useful to reduce the “comfort gap” by minimizing the assumptions when developing the simulation models.

Dynamic Building Energy Simulation (DBES) modeling is a useful way to calculate the energy saving through retrofitting of the existing building stock. However, Professionals are concerned about the discrepancy between the calculated and actual energy savings which is known by the performance gap. Calibrating the DBES models is a crucial step before heading towards the optimization step. The existing standardized statistical indices depend on energy bills to perform the calibration. These indices are not easily applied in developing countries where a combination of fuels is sometimes used for heating. In this paper, the heating load in a single house in Hebron, Palestine was modeled as internal gain. Then the model was calibrated using internal environment measurements (internal temperature) that were taken through two monitoring phases for a single house in Hebron, Palestine. A validation method for a single house was presented using the internal temperature depending on the monitoring phases. The results show that the model was calibrated and can be used for optimization.

Several studies have demonstrated the capability of data-driven modelling based on on-site measurements to characterise the thermal performance of building envelopes. Currently, such methods include steady-state and dynamic heating experiments and have mainly been applied to scale models and unoccupied test buildings. Nonetheless, it is proposed to upscale these concepts to characterise the thermal performance of in-use buildings based on on-board monitoring (OBM) devices which gather long-term operational data (e.g., room temperatures, gas and electricity consumption...). It remains, however, to be proven whether in-use data could be a cost-effective, practical and reliable alternative for the dedicated tests whose more intrusive measurements require on-site inspections. Furthermore, it is presently unclear what the optimal experimental design of the OBM would be and which data analysis methods would be adequate. This paper presents a first step in bridging this knowledge gap, by using on-board monitoring data to characterise the overall heat loss coefficient (HLC) [W/K] of an occupied, well-insulated single-family house in the UK. With the aid of a detailed building physical framework and specifically selected data subsets a sensitivity analysis is carried out to analyse the impact of the measurement set-up, the duration of the measurement campaign and the applied data analysis method. Although the exact HLC of the building is unknown and no absolute errors could hence be calculated, this paper provides a new understanding of the decisions that have to be made during the process from design of experiment to data analysis. It is demonstrated that such judgements can lead to differences in the mean HLC estimate of up to 89.5%.

The paper introduces a novel indicator of urban built form termed Form Signature. Generic models of four urban built forms are developed, including pavilion, terrace, court and a newly introduced tunnel-court is used to compare and contrast their land-use performance and density characteristics. Selecting plot ratio and site coverage as the most popular and appropriate density indicators, the simultaneous relationship to each of the considered urban built forms is shown graphically with the number of storeys, plan depth and cut-off angle as the main variables of interest. For existing urban areas, the resulting graphs provide a robust tool for statistical analysis of contexts such as climate, economy, energy and crime potential and establish their relationship to form and density. To show the value of the contribution, analysing 32 case studies from 19 cities in different global locations showed an insignificant relationship between climate and form/density of urban areas, whilst practically depicting that urban areas built in court form acquire higher cut-off angle compared to terrace form urban developments. For planning the future urban areas, the resulting relationships provide application-oriented urban planning tool to facilitate the most effective land-use method in order to achieve sustainable cities. Examples showing the potential of the tool for future statistical energy and social analysis of urban areas are provided. Finally, a relative comparison shows that the newly-introduced tunnel-court form achieves the greatest density while pavilion achieves the lowest.

The domestic sector uses the majority of the energy consumed in Palestine. The Palestinian Central Bureau of statistics (PCBS) performs periodic statistics regarding the average energy consumption of the households, but there is no up to date breakdown of the energy consumption in the residential sector. The Palestinian energy sector main challenges are the high fuel prices, lack of sustainable consumption and energy insecurity. Developing energy policies and studying the potential of shifting towards more independent and sustainable energy sources need a clear understanding of the current energy consumption. A survey was used to collect relevant quantitative and qualitative data. The total number of households in Hebron who responded to the survey was 322 households. The survey covered physical characteristics of the dwellings, socioeconomic features of the households in addition to the pattern of heating the spaces, quantity and type of fuel used for heating. On average the households heated only 9.2% of the total area of their houses during the winter days. The survey revealed that households spend 3.5%e21.6% of their monthly income on space heating during winter. The main contribution to knowledge of this paper is a regression model to estimate energy consumption based on the data collected from the survey. The regression model is developed with an R2 adjusted 0.606 indicating 60.6% accuracy of the predicted energy consumed for heating. The regression model depends on 14 parameters which include the type of settlement, physical characteristics of the dwelling that are housing typology, level of thermal insulation of the walls, the main building materials and the housing age. It also depends on socioeconomic parameters which are the family monthly income and the occupancy period. Moreover, the type of the heating system used, the number of heated months and the nominal heated area were influential parameters in this model. The significance of this paper stems fro

Predicting the energy performance of buildings is important to optimize the energy consumption. Building Energy Performance Simulation (BEPS) is a key tool that is used to predict the environmental performance of buildings. Much work has been done that conforms a gap between predicted and measured energy consumed in buildings due to a range of influencing factors. Understanding the causes of performance gap can help in reducing it between design targets and actual performance. On the other hand, there is a convincing evidence that climate is changing and that we will be facing different climatic scenarios in the future. Buildings should be designed to be able of dealing with future climatic changes using mitigation and adaptation measures. Building Energy Performance Simulation (BEPS) can be used to estimate the energy performance of buildings and their indoor environments based on future climatic scenarios and to assess the different design options. This paper explores the main aspects that need consideration when predicting the energy performance of buildings under future climatic conditions. The research conducts a critical literature review engaging with previous knowledge in the field. It also sheds light on the way of producing future weather files.

With rapid economic growth and urban expansion in China, the Chinese building sector is now facing the huge challenge of balancing its energy demand and pollution. In order to minimize the environmental impact, the Ministry of Housing Urban-Rural Development (MOHURD) has set an ambitious energy reduction target requiring that 30% of all new constructions to be green by 2020. This paper presents comparative analysis of two environmental rating systems: the latest version of Chinese Green Building Label (GBL 2014) released by the MOHURD in order to promote the market transformation of green buildings and Building Research Establishment Environmental Assessment Method (BREEAM 2014), the widely recognised environmental assessment methodology in the global construction industry. To compare the two environment assessment standards, a public office building currently under construction in Fujian (China) has been used as a case-study to rate its environmental credentials using both BREEAM and GBL. Results have shown that although both standards use a similar methodology, they require different levels of input data and may result in different ratings for the same building.

This paper presents the findings of a post-occupancy evaluation (POE) applied to a building in the UK. The design of the building was generated through an externally funded research project over two years from 2005 to 2007. The construction of the building was completed in 2010. After a period of occupancy, a POE of the building was carried out in 2015. The POE offered an opportunity to investigate the effect of occupant behaviour on the performance of the building and their level of comfort and satisfaction. We adopted a field survey method to evaluate the comfort and satisfaction of users by asking them a series of questions to analyse how they felt in different parts of the building throughout the course of the year. In our analysis, the users were prompted to provide a subjective measure of the building regarding a range of internal conditions such as air temperature, humidity, air movement, air quality, daylight, artificial light, and noise. The analysis supports the notion that in naturally-ventilated buildings some users may find the building to be hot in summer while cold in winter. The high level of control the users have over the operation of the building contributes to their comfort and satisfaction. The users demonstrated a tendency to be satisfied despite environmental factors and to forgive some aspects of the building which are not performing as they should. The paper offers a perspective on statistical user satisfaction in a low occupancy building and attempts to explain the role of workplace wellbeing on occupant perception of comfort in this case.

Hometown of Oversea-Chinese is a special phenomenon in the history of Chinese near-modern development, mainly in the east and south coast of China. At the beginning of last century, a large number of coastal residents moved overseas for living. After decades of efforts, they invested back hometown to build houses. These residence layouts consist both local traditional culture and foreign features, forming a special landscape. In recent years, economic globalization has promoted rapid urbanization, which leads massive population flowing from rural to urban areas. Cities eroded the countryside field and evacuated the rural labor force, leading to a large number of abandoned deteriorated urban villages, including the hometown of Oversea-Chinese. This paper focuses on the regeneration of urban villages in hometown of Oversea-Chinese. With the influence of global industrialization and rapid urbanization in recent decades in China, a large number of Oversea-Chinese residence groups have become empty and decayed urban villages gradually. However, they are different from urban villages in other parts of China, as they have unique cultural features and historical value, therefore research on the regeneration of this type of urban villages not only contribute to local economic development but also is closely related to the hot topic of how to maintain cultural differences under the process of globalization. We surveyed their formation process, historical and cultural characteristics and put forward some strategies of regeneration from the three aspects of society, economy and environment: explore history culture to strengthen the bond with Oversea-Chinese, develop cultural and creative industries and appropriate tourism to promote economic activities and improve the environment by government-led planning