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Occupant behavior can lead to considerable uncertainties in thermal comfort and air quality within buildings. To tackle this challenge, the use of probabilistic controls to simulate occupant behavior has emerged as a potential solution. This study seeks to analyze the performance of free-running households by examining adaptive thermal comfort and CO2 concentration, both crucial variables in indoor air quality. The investigation of indoor environment dynamics caused by the occupants' behavior, especially after the COVID-19 pandemic, became increasingly important. Specifically, it investigates 13 distinct window and shading control strategies in courtyard houses to identify the factors that prompt occupants to interact with shading and windows and determine which control approach effectively minimizes the performance gap.

This paper compares commonly used deterministic and probabilistic control functions and their effects on occupant comfort and indoor air quality in four zones surrounding a courtyard. The zones are differentiated by windows facing the courtyard. The study utilizes the energy management system (EMS) functionality of EnergyPlus within an algorithmic interface called Ladybug Tools. By modifying geometrical dimensions, orientation, window-to-wall ratio (WWR) and window operable fraction, a total of 465 cases are analyzed to identify effective control scenarios. According to the literature, these factors were selected because of their potential significant impact on occupants’ thermal comfort and indoor air quality, in addition to the natural ventilation flow rate. Additionally, the Random Forest algorithm is employed to estimate the individual impact of each control scenario on indoor thermal comfort and air quality metrics, including operative temperature and CO2 concentration.

The findings of the study confirmed that both deterministic and probabilistic window control algorithms were effective in reducing thermal discomfort hours, with reductions of 56.7 and 41.1%, respectively. Deterministic shading controls resulted in a reduction of 18.5%. Implementing the window control strategies led to a significant decrease of 87.8% in indoor CO2 concentration. The sensitivity analysis revealed that outdoor temperature exhibited the strongest positive correlation with indoor operative temperature while showing a negative correlation with indoor CO2 concentration. Furthermore, zone orientation and length were identified as the most influential design variables in achieving the desired performance outcomes.

It’s important to acknowledge the limitations of this study. Firstly, the potential impact of air circulation through the central zone was not considered. Secondly, the investigated control scenarios may have different impacts on air-conditioned buildings, especially when considering energy consumption. Thirdly, the study heavily relied on simulation tools and algorithms, which may limit its real-world applicability. The accuracy of the simulations depends on the quality of the input data and the assumptions made in the models. Fourthly, the case study is hypothetical in nature to be able to compare different control scenarios and their implications. Lastly, the comparative analysis was limited to a specific climate, which may restrict the generalizability of the findings in different climates.

Occupant behavior represents a significant source of uncertainty, particularly during the early stages of design. This study aims to offer a comparative analysis of various deterministic and probabilistic control scenarios that are based on occupant behavior. The study evaluates the effectiveness and validity of these proposed control scenarios, providing valuable insights for design decision-making.

The paper aims to determine the thermal comfort perception of schoolchildren from a warm and humid environment. There is a concern about the effect of high temperature on the health and academic performance of schoolchildren.

Objective and subjective methodological approaches were adopted to collect data during the fieldwork in the selected primary schools. ASHRAE adaptive comfort model was adopted to analyze the data.

The paper provided empirical results about the comfort requirements of schoolchildren from the warm and humid environment. During the occupied school time, the studied schoolchildren were found to tolerate temperatures higher than the upper limit temperature recommended by ASHRAE Standard 55. The paper recommends that the studied children may not need any active ventilator to be thermally comfortable during the occupied school hours

The paper found the range of temperatures that schoolchildren from the warm and humid environment can adapt to. The information may be useful to architects, engineers and facility managers

The development of strategies for energy efficiency optimization in buildings has become a fundamental way to reduce buildings’ environmental impact because the amount of energy consumed by buildings is responsible for one‐third of total global energy consumption. The purpose of this research is to evaluate the performance of buildings in terms of their indoor operative temperature dynamics considering the impact of other neighbouring buildings. The goal of the paper is to verify whether close spatial relationships of buildings and urban morphology within a local network of buildings could cause a considerable effect on indoor thermal behaviour.

The authors simulated buildings in an existing city block in Albany, New York, USA. The block consisted of six single‐family houses.

The results demonstrate that buildings mutually impact the indoor thermal behaviour of other buildings in the network with indoor operative temperature differences of over 20 percent in summer and over 40 percent in winter for the test case examined. The research also compares this result with improvements in indoor operative temperature achieved through traditional envelope improvements. It was found that during the summer, certain envelope improvement strategies have nearly the same impact in terms of indoor thermal behaviour. During winter, the presence of neighbouring buildings causes a variation that is more than double the value of the effect caused by a typical envelope modification.

It is concluded that this mutual impact on indoor operative temperature across spatially proximal buildings should be included in dynamic analyses of buildings. Future research should examine the effect of these indoor operative temperature deviations on the energy performance predictions of buildings in urban and quasi‐urban settings.

Due to the increasing frequency of extreme weather and densifying urban landscapes, residences are susceptible to heat-related discomfort, especially those in a naturally ventilated built environment in tropical climates. Indoor thermal comfort is thus paramount to building sustainability and improving occupants' health and well-being. However, to assess indoor thermal comfort considering the urban context, it is conventional to use questionnaire surveys and monitoring units, which are both case-centric and time-intensive. This study presents a dynamic computational thermal comfort modeling framework that can determine indoor thermal comfort at an urban scale to bridge this gap.

The framework culminates in developing a deep learning model for predicting the accurate hourly indoor temperature of urban building stock by the coupling urban scale capabilities of environment modeling with single-building dynamic thermal simulations.

Using the framework, a surrogate model is created and verified for Dharavi, India's informal urban settlement. The results indicated that the developed surrogate model could predict the building's indoor temperature in several complex new urban scenarios with different building orientations, layouts, building-to-building distances and surrounding building heights, using five different random urban representative scenarios as the training set. The prediction accuracy was reliable, as evidenced by the mean bias error (MBE) and coefficient of (CV) root mean squared error (MSE) falling between 0 and 5%. The findings also showed that if the urban context is ignored, estimates of annual discomfort hours may be inaccurate by as much as 70%.

The developed computational framework could help regulators and policymakers engage in more informed and quantitative decision-making and direct efforts to enhance the thermal comfort of low-income dwellings and informal settlements.

Up to this point, majority of literature that has been presented has concentrated on building a body of knowledge about urban-based modeling from an energy management standpoint. In contrast, this study suggests a dynamic computational thermal comfort modeling framework that takes into account the urban context of the neighborhood while examining the indoor thermal comfort of the residential building stock.

The paper aims to clarify the relationship between energy flexibility and building components and technologies. It determines the energy flexibility potential of buildings in relation to their physical characteristics and heat supply systems with respect to external boundary conditions.

The emphasis of the evaluation is based on the timing and the amount of shiftable and storable thermal loads in buildings under defined indoor thermal comfort conditions. Dynamic building simulation is used to evaluate the potential of selected building characteristics to shift heating loads away from peak demand periods. Insights on the energy flexibility potential of individual technologies are gained by examining the thermal behaviour of single-zone simulation models as different input parameters are varied. For this purpose, parameters such as envelope qualities, construction materials, control systems for heating are modified.

The paper provides a comprehensive understanding of the influence of the different building parameters and their variations on their energy shifting potential under “laboratory conditions” with steady boundaries. It suggests that the investigated boundary conditions such as outside temperature, infiltration, envelope quality and user behaviour, which influence the heating load of a building, also influence the resulting potential for energy flexibility. The findings show that the combination of a slowly reacting heat transfer system, such as concrete core activation and a readily available storage mass in the room, and a high insulation standard proved to have a high potential to shift heating loads.

In this paper, energy-flexible components were evaluated in a steady-state simulation approach. Outside temperature, solar irradiation and internal loads over the simulation duration were set constant over time to provide laboratory conditions for the potential analysis. On the basis of both duration and performance of the load shifting or storage event, the components were then quantified in a parametric simulation. The determined energy flexibility is directly related to the power of the heating, cooling, hot water and ventilation system, which can be switched on or off. In general, it can be seen that high power (high loads) demand usually can be switched on and off for a short duration, and low power demand usually for a longer duration. The investigated boundary conditions such as outside temperature, infiltration, envelope quality and user behaviour, which influence the load of a building, also influence the resulting potential for energy flexibility. Higher insulation standards, for example, lead to lower loads that can be switched on or off, but increase the duration of the event (flexibility time). So that, in particular, the shiftable load potential is low but results in a long switch-off duration. Furthermore, passive storage potential in buildings like the storage mass inside the room and the type of heat/cooling transfer system can affect the flexibility potential by more than three times. Especially the combination of a high storage mass and a concrete core heat transfer system can significantly increase the flexibility.

Recent climate change projections estimate that the average summertime temperature in the southern part of Great Britain may increase by up to 5.4°C by the end of the century. The general consensus is that projected increases in temperature will render British dwellings vulnerable to summer overheating and by the middle of this century it may become difficult to maintain a comfortable indoor environment, if adaptation measures are not well integrated in the design and operation of new dwellings, which are likely to remain in use beyond the 2050s. The challenge is to reduce overheating risks by integrating building and user adaptation measures, to avoid energy intensive mechanical cooling. Developing guidelines and updating building regulations for adaptation, therefore, requires an understanding of the baseline scenario; i.e. the performance of existing buildings in future climates.

This paper aims to investigate the performance of new-build multi-occupancy British dwellings for human thermal comfort in the present-day and projected future climates in four regional cities: Birmingham, Edinburgh, London and Manchester. Evaluations are carried out by a series of dynamic thermal simulations using widely adopted threshold temperature for overheating, as well as adaptive thermal comfort standards. This study thus offers a unique perspective on regional variations of performance and provides a clearer snapshot because of the use of more appropriate adaptive comfort standards in the evaluations. Finally, the paper sheds light on possible personal and building adaptation measures to alleviate overheating risks.

This paper sets out to highlight several aspects of a project, aimed at developing an advanced thermal comfort guideline, based on the adaptive thermal comfort theory.

The paper introduces the new Dutch adaptive guideline for thermal comfort. The initial method exceeding hours (TO) is discussed, as well as the more recent method of weighted temperature exceeding hours (GTO). An evaluation of the practical and theoretical shortcomings of the TO and GTO methods is discussed, as well as the rationale behind the adaptive ATG guideline. Furthermore, the results are presented of computer simulations in which the predictions of the different methods are compared. Productivity effects of the new guideline are also discussed, as well as the implications for cooling system sizing and energy efficiency.

The adaptive temperature limits (ATG) guidelines appears to be a more reliable method for the assessment of thermal comfort, in particular for passive, free‐running buildings, compared with the PMV‐based method of weighted temperature exceeding hours (GTO). Furthermore, the ATG method allows for a wider temperature range for Alpha type buildings and gives more opportunity for the development of sustainable, naturally ventilated buildings and limiting cooling energy.

Although the new ATG method shows promising results, more research is needed. The exact distinction between Alpha and Beta is still subject to further research, as well as the question whether a certain amount of exceeding hours of the ATG limits should be accepted.

The ATG method is being used in The Netherlands for the assessment of thermal comfort in the design stage as well as in the assessment of the performance of buildings in use.

This paper discusses the first application of the adaptive thermal comfort theory in a practical guideline.

The purpose of this paper is to develop a set of affordable retrofit packages that can be applied to existing residential buildings in hot-humid regions to improve occupants’ thermal comfort and reduce energy consumption.

A critical review of relevant literature to identify passive design strategies for improving thermal comfort and reducing energy consumption in hot-humid climates with focus on the building envelope was conducted in addition to a simulation study of an existing building typology in study area.

There is enormous potential to reduce energy costs and improve thermal comfort through building retrofit packages which is a recent concept in developing countries, such as Nigeria. Analysing the results of the retrofit interventions using building energy simulation helped in developing affordable retrofit packages which had optimum effect in improving indoor comfort temperature to the neutral temperature specified for hot humid Nigeria and further down to 3°C less than that of the reference building used. The use of passive design strategies to retrofit the building might help homeowners reduce their annual energy consumption by up to 46.3 per cent just by improving the indoor thermal comfort.

In addition to improving thermal comfort and reducing energy consumption, this research identified affordable retrofit packages and considered its cost implications especially to low-income earners who form a larger population of Lagos, Nigeria, as this was not considered by many previous researchers.

Heat gain in buildings occurs due to heat transfer through the building fabric or envelope, especially the walls and roof. The purpose of this paper is to identify and recommend the suitable wall materials for better thermal performance in buildings in warm and hot climatic zones of India. As India lies between the tropic of cancer and the equator, the solar radiation from the sun falls more on the walls than the roofs of the buildings. Thus, it is imperative to protect the walls from heat gain to promote thermal comfort in naturally ventilated buildings and reduce the energy loads due to artificial cooling systems in air-conditioned buildings.

In this paper, an investigation of heat flow characteristics in steady-state and the transient state for five different uninsulated wall structures using computational fluid dynamics (CFD) software has been carried out. The climate conditions at Madurai, India have been considered for this study.

The findings of the study revealed that aerated autoclaved concrete (AAC) and hollow clay blocks (HCB) for external walls in naturally ventilated buildings in warm climatic regions could improve the building’s thermal performance index and reduce peak indoor operative temperature by about 6°C–7°C. The results of steady-state and transient state analysis were found to be in good agreement with the results of the reviewed literature.

Over the past few decades, only very few architects and builders have been successful in influencing their clients to accept alternate materials such as AAC blocks, HCB, stabilized earth blocks, adobe blocks, fly-ash bricks as an alternate to conventional bricks in an attempt of highlighting their benefits, such as; materials that are easily available, more energy-efficient, can withstand the extreme weather conditions, promote thermal comfort and cost-effective. This paper provides strong evidence that AAC and HCB blocks are the most appropriate materials for improving the thermal performance of envelope walls in regions where the outdoor temperatures are above 40°C.

This paper has made an attempt to identify the appropriate wall materials for effective thermal performance in warm and hot climates. A comparative analysis between five different wall types under the existing solar conditions has been analyzed using CFD simulation study in steady-state and transient conditions under summer conditions and the appropriate wall materials have been suggested. There has been no attempt carried out so far to analyze the thermal performance of different walls using 24 h transient approach in CFD.

To provide input data to design and energy performance calculations of buildings and ventilation, heating, cooling and lighting systems.

European directive for energy performance of buildings was approved in the beginning of 2003. The transition period is 3‐6 years depending on the article. European Standardisation Organisation (CEN) has drafted several standards to help the member countries implementing the directive. One of these is the “Criteria for the indoor environment including thermal, indoor air quality (ventilation) light and noise.” The standard has been developed based on existing international standards and guidelines for the indoor environment taken into account the latest results from published research.

The standard specifies design values of indoor environment, values to be used in energy calculations, and methods how to verify the specified indoor environment in the buildings. The paper describes some of the principles used in standards, and gives examples presented in the standard. The standard covers all building types but the paper is focuses on the non‐residential buildings, numeric examples are given only for offices.

The draft standard is under international review process during writing this paper, and subject to changes. The standard give default criteria for the indoor environmental parameters, which can be used if no national requirements are available.

This paper describes the indoor environmental parameters, which are important for people's health, comfort and energy consumption of buildings. This will help users to select more uniform input data for energy calculations.