Comfort In Residential Buildings Research Articles

Optimal HVAC setpoints for energy efficiency and thermal comfort in Chinese residential buildings

The easiest way to improve energy efficiency and thermal comfort in existing buildings is to adjust setpoints. However, although Chinese standards regulated the heating and cooling setpoints for different climate zones in China, they lacked consideration for occupants’ thermal comfort and ignored the ventilation setpoints. Therefore, this study aimed to identify optimal heating, cooling, and ventilation setpoints at the design stage to enhance building energy performance and indoor thermal comfort in Chinese residential buildings. This study used DesignBuilder to simulate the energy usage and thermal comfort with different setpoints and judged which combination was the best. To conduct this study across the whole of China, the typical cities in different climate zones were selected by using machine learning. Results indicated that adjusting setpoints in Harbin, Beijing, and Shanghai could increase comfortable days by 43.95 %, 54.23 %, and 23.36 % respectively, with minimal impact on energy usage. In Guangzhou, energy usage could be reduced by 7.56 % with a 5.91 % decrease in comfortable days, while Kunming could see an 11.11 % increase in comfortable days with a 5.92 % rise in energy consumption. Additionally, sensitivity analysis revealed that activity template variation was most critical for energy usage in Harbin, Beijing and equipment power density variation was most important for thermal comfort in Shanghai, Guangzhou, and Kunming. Furthermore, proposed setpoint combinations demonstrated resilience to future weather conditions in most typical cities, except for Guangzhou. These findings provide valuable insights for designers and researchers aiming to retrofit residential buildings, emphasizing the importance of considering both energy efficiency and occupant comfort. This study introduces innovative approaches like comprehensive setpoint optimization and machine learning for typical city selection, providing practical solutions to improve energy efficiency and thermal comfort in residential buildings.

Economic model predictive control for building HVAC system: A comparative analysis of model-based and data-driven approaches using the BOPTEST Framework

Model Predictive Control (MPC) has demonstrated its capability to significantly enhance energy efficiency while ensuring indoor comfort. This study focuses on the development and fair comparison of two Economic Model Predictive Control(EMPC) frameworks with the goal of optimizing demand response for utility cost reduction and ensuring thermal comfort in residential buildings. The first framework, known as RC-MPC, utilizes a reduced-order thermal Resistance–Capacitance network model to represent the thermal dynamics of the building. It formulates the optimization problem as a Linear Programming (LP) task, which is solved using CPLEX. The second framework, known as ANN-MPC, employs an Artificial Neural Network model capture the thermal behavior of the building, It addresses a non-convex optimization problem through projected stochastic gradient descent. To evaluate the performance of these frameworks, experiments are conducted using a single-zone dwelling within the BOPTEST framework. The results demonstrate that both approaches effectively reduce operational costs and enhance comfort, achieving comparable performance and outperforming the baseline Rule-Based Control (RBC) method. The discomfort reductions range from 30% to 95%, and energy expense savings range from 17% to 34%. Furthermore, the study examines the impact of various MPC hyperparameters. The findings highlight that a proper control horizon and formulating the objective function accurately are crucial for achieving optimal control performance. Additionally, tightening the comfort range is found to be important in managing the comfort violations, and the choice of solver can influence both the control performance and computational efficiency.

Performance evaluation of Trombe wall systems in enhancing thermal comfort in residential buildings of Subtropical highland climate - A case of Hamirpur, Himachal Pradesh, India

Performance evaluation of Trombe wall systems in enhancing thermal comfort in residential buildings of Subtropical highland climate - A case of Hamirpur, Himachal Pradesh, India

Multi-objective optimization of residential building energy consumption, daylighting, and thermal comfort based on BO-XGBoost-NSGA-II

The energy consumption, daylighting, and thermal comfort of buildings directly affect the three key goals of residents. However, there is little research on the optimization of energy consumption, daylighting, and thermal comfort in residential buildings in China. Therefore, this study proposes an optimization framework that combines Bayesian optimization with extreme gradient boosting trees (BO-XGBoost) and non-dominated genetic algorithm-II (NSGA-II) to study the multi-objective optimization of residential building performance. This paper first uses Grasshopper to simulate and obtain a dataset through Latin hypercube sampling (LHS). BO-XGBoost is used to establish the regression relationship between building envelope design parameters and residential building performance. Then, the obtained regression model is used as the fitness function of NSGA-II to get the Pareto optimal solution set. Finally, the ideal point method is used to obtain the optimal combination of building envelope structure parameters for residential buildings. Taking a residential building in a hot summer and cold winter area as an example, the effectiveness of this method is verified. The results show that (1) BO-XGBoost has excellent predictive performance, with R2 values of 0.997, 0.960, and 0.994 for energy consumption, thermal comfort, and daylighting, respectively. (2) The proposed BO-XGBoost-NSGA-II can effectively achieve multi-objective optimization. Compared with the initial scheme of the case building, energy consumption is reduced by 44.1%, thermal comfort index is reduced by 10.9%, and daylighting performance is improved by 1.7%. Therefore, the proposed method can effectively optimize the performance goals of residential buildings and provide practical ideas for similar problems.

Evaluation of the Effectiveness of Passive Design Strategies in Achieving Thermal Comfort in Residential Buildings in Egypt

This study aims at thermal comfort improvement in residential buildings through utilization of passive design strategies and energy efficiency measures. The study investigates the impact of passive strategies on thermal comfort in hot dry climate of Egypt. A climatic analysis of three cities: Aswan, Cairo and Alexandria was conducted to examine passive design strategies’ efficacy. Thermal comfort in a residential building was examined by DesignBuilder simulation software. Annual simulations were performed on the model where several passive design strategies were applied. Passive design strategies’ potential was quantified and a parametric analysis was conducted for thermal comfort improvement. The results demonstrate that applying passive design strategies can be effective in reducing discomfort hours in hot climate. Comfort hours could be increased from 22.6% to 33.1 % in Aswan, while in Cairo can be increased from 31.1% to 38.6 %, and in Alexandria from 36.9% to 46 %. The research findings could be used by architects for thermal comfort improvement in residential buildings.

Comparative Analysis of Thermal Comfort in Residential Buildings: A Study of the impact of Urban Density, Height, and Layout Patterns in the Context of Dhaka

The thermal environment of residential spaces significantly influences residents’ physical and emotional well-being, affecting daily activities and overall quality of life. With a growing global emphasis on sustainability, energy efficiency, and healthy living understanding how architectural and urban elements impact thermal comfort becomes crucial. This study focuses on Dhaka, Situated in a tropical monsoon climate, this context presents unique challenges for ensuring thermal comfort within structures. The research conducts a comparative analysis of two residential structures with different layout configurations but similar orientations, situated in diverse urban settings with varying levels of density, exposure and openings. Investigating the influence of urban density, adequate openings, shading within the plan layout, and vertical positioning of structures on residents’ thermal comfort, the study employs extensive field data collection, observation, questionnaire survey and simulation. The findings indicate that high-density residential areas offer advantages such as reduced direct heat intake and loss, yet may encounter challenges including limited natural ventilation and increased heat absorption, resulting in elevated indoor temperatures. Conversely, low-density areas with open spaces benefit from enhanced natural ventilation and reduced heat accumulation, leading to improved thermal comfort, particularly in hot and humid conditions. This paper underscores the significance of considering architectural and urban aspects in residential buildings in Dhaka’s context to ensure the thermal comfort and well-being of residents. By addressing these factors, designers and urban planners can contribute to creating healthier and more sustainable living environments amidst changing climatic conditions.

Enhancing sustainable facade design: A Belgrade case study

This research examines the potential of widespread facade systems to improve energy performance and enhance user comfort in residential buildings. Utilizing Design Builder software (Version 5.0.3.7), the study specifically aimed to reduce heating energy consumption, a significant concern in the climatic conditions of Serbia. The methodology incorporated both technical performance assessments and economic analyses, evaluating the economic viability through metrics such as Return on Investment (ROI), Net present value (NPV), and Internal rate of return (IRR). The multi-criteria evaluation framework employed allowed for a comprehensive analysis, balancing technical performance with economic and qualitative factors to identify the most favorable facade systems. By addressing both the immediate economic returns and longer-term benefits, this research contributes to a more sustainable and economically feasible building practice.

TRANSFORMATION OF PASSIVE DESIGN ELEMENTS FOR ACHIEVING THERMAL COMFORT IN RESIDENTIAL BUILDINGS OF MANSEHRA CITY, PAKISTAN FROM 1990 TO 2019

Among the most evolving issues in recent years, there is growing concern over global warming throughout the world. The construction industry has been considered among the major contributors to global warming. The use of building envelope along with the heating, cooling, and lighting design, operations, and infrastructures are the prime factors of this contribution. Due to this reason, the thermal comfort of buildings has become a major concern in building design globally. The following research explored the building design elements used for thermal comfort in residential buildings of Mansehra City of Khyber Pakhtunkhwa province in Pakistan and analyzed its transformation during the last three decades. The study proceeded by documenting and comparing various design elements to understand their transformation within documented time periods i.e. thermal mass, fixed shading devices, and the ratio of open and closed spaces. These elements were evaluated for their effectiveness in providing thermal comfort. It was concluded that these design elements have been adapted and modified with time with little concern for sustainability. It was found that the focus has shifted from building orientation, sun path, and wind directions to aesthetically pleasing forms only which makes them saleable and lack human comfort. The use of passive means to achieve thermal comfort was neglected. The research concludes by suggesting incorporation of appropriate thermal comfort components and methods into effective solutions for improved building designs, lower energy demand, and a better indoor atmosphere. Keywords: Thermal Comfort, Passive Design, Residential Building, Mansehra City, Global Warming

Learning from Vernacular and Integrating Retrofitting Techniques to Enhance Thermal Comfort in Residential Buildings: Insights from Tiruchirapalli, India

Learning from Vernacular and Integrating Retrofitting Techniques to Enhance Thermal Comfort in Residential Buildings: Insights from Tiruchirapalli, India

Decarbonising building heating and cooling: Designing a novel, inter-seasonal latent heat storage system

The global heating and cooling demands have increased to mitigate the effects of the rise in extreme weather events due to climate change. This has led to an increase in global greenhouse gas emissions due to the use of fossil fuels to meet these demands. The current study evaluates how an alternative low-carbon heating and cooling system may provide thermal comfort in residential buildings, specifically in regions that have a humid temperature oceanic climate-for example, the United Kingdom. To meet the net-zero emissions targets set in the United Kingdom by 2050, greenhouse gas emissions generated from heating in residential buildings must fall by 95 %. The leading decarbonisation strategy proposed by their government requires the electrification of the heating system through the installation of heat pumps. Consequently, the average electricity consumption per household is expected to increase. This will impose considerable pressure on electricity networks to source additional (ideally renewable) capacity, which will ultimately be costly. To circumvent this issue, the current study proposes a novel alternative method of providing nearly zero-carbon space and water heating, that can operate almost independently of the electricity grid. This requires the use of solar energy as the thermal energy source, and a solid-liquid phase change material as an inter-seasonal energy storage medium. A design optimisation study was thereafter carried forward to showcase the capability of such a system for a semi-detached house in London, United Kingdom.

ENERGY OPTIMIZATION OF MID-RISE BUILDINGS IN TROPICAL AREAS: A RESIDENTIAL SITE CASE STUDY

Residential buildings and living conditions have greatly changed over the last two decades. In fact, with a few exceptions, current buildings are not the kind of habitats belonged to today. Due to the development of innovative materials, products and construction methods, the construction of environmentally friendly buildings with better economic efficiency seems essential. The present study seeks to provide simple and practical solutions to reduce energy consumption and develop comfort in residential buildings in cities influenced by hot climatic conditions. To this end, a 4-storey residential building in the city of Ahvaz, Iran, is simulated by Design Builder Software (which uses Energy plus engine) to investigate the impact of alternative roofing and facade materials, awning, windows, and others, on energy efficiency. The results show that using rockwool and aluminum composite panels (ACP) facade, pumice concrete roofing, double glazed windows, vertical awning of a 70 cm height, and a balcony of 50 cm depth are the best composition to thermal reinforcement for residential buildings and decrease energy consumption. Key Words: Energy Consumption Optimization, Thermal Comfort, Residential Complex

Investigating the Influence of Thermal Conductivity and Thermal Storage of Lightweight Concrete Panels on the Energy and Thermal Comfort in Residential Buildings

Phase change materials (PCM) are integrated into lightweight concrete (LWC) panels to increase their thermal mass. However, the integration of PCM into LWC also increases the thermal conductivity of the panels, which may have a negative impact. This study investigated the impact of thermal resistance and storage of LWC panels on thermal comfort and energy use in buildings. Six different LWC panels with varying levels of thermal conductivity and storage were developed using various combinations lightweight aggregates and PCM. The experimentally measured properties were used in building simulation software EnergyPlus V9.3 to calculate overheating and building energy consumption for each panel. The result showed that thermal mass influences severe discomfort hours more than thermal resistance. However, the level of influence depends on the position of the panels compared to the insulation layer. The presence of an insulation layer reduced the energy savings rate. The cooling energy consumption was more influenced by the thermal mass, whereas the heating was more influenced by the resistance of the wall. Overall, the LWC panel with the highest thermal mass was the best to reduce severe discomfort hours and energy consumption despite having the highest thermal conductivity. The outcome of this study can help to design an external building envelope with PCM panel as per user requirements, which could be to reduce overheating or cooling only, heating only, or both cooling and heating.

Numerical Analysis of Wind Effects on a Residential Building with a Focus on the Linings, Window Sills, and Lintel

This article deals with the investigation of wind effects on a façade of a rectangular residential building with explicit modelling of the windows for specific wind conditions. The external wind pressure coefficients were treated on the façade and at the places of the window sills, linings, and lintel for the direction of the wind from 0° to 90° with increments of 22.5°. For a detailed analysis, the CFD simulation using Ansys Fluent was used. The method selected for the CFD simulation solution and its setting (quality of meshing, horizontal homogeneity of the boundary layer, etc.) were verified by known results of similar objects. The purpose of this analysis is to show how important it is to consider wind effects to determine the suitable placement of passive ventilation devices. Research shows the potential optimal position of ventilation units in terms of favourable pressure distribution. Zones with negative pressure and corners or façades in a wake are not suitable for applying passive ventilation units. The results can serve as a basis for designers to achieve optimal comfort in residential buildings.

The Impact of Meteorological Changes on Human Comfort in Residential Buildings

This research article investigates the effect of meteorological changes on the comfort of residents in Imo State, Nigeria, which is situated in a tropical monsoon climate. The study aims to assess the state of the indoor environment in residential buildings in Imo State, considering thermal changes caused by meteorological variations. A case study approach was adopted, focusing on a selected residential building in Umuasonye, Orji, Owerri North, Imo State. The study spanned a period of 10 years, from 2011 to 2021, and included physical observation, measurement, and qualitative analysis of the collected data. A case study approach was employed to overcome limitations in accessing a large sample size of individual residential buildings. The selected residential building in Umuasonye, Orji, Owerri North, Imo State served as a representative example for the study. Data collection involved physical observation, measurement, and qualitative analysis over a 10-year period, from 2011 to 2021. This approach allowed for a comprehensive understanding of the indoor environment and its relationship with meteorological changes. Findings reveal significant climate and weather changes in Imo State, leading to thermal variations in building spaces. The study assesses the impact on resident comfort and identifies adaptive strategies employed. During dry seasons, residents utilized cooling systems, ventilation, and reduced hot water usage. In wet seasons, measures such as closing windows, wearing thick clothing, and increased hotwater usage were observed. This research provides valuable insights into the impact of meteorological changes on resident comfort in Imo State, Nigeria. It highlights the importance of climate-responsive building design and systems, showcasing adaptive strategies employed by residents. The case study approach contributes to knowledge for architects, building industry stak eholders, and users interested in promoting climate-responsive buildings and systems

A Review of Thermal Comfort in Residential Buildings: Comfort Threads and Energy Saving Potential

Residential buildings instigate a vital role in creating a safe and comfortable indoor living environment. The phenomenon of overheating, an impact of climate change, can cause a negative effect on residents’ productiveness and heat-related illnesses and can even force high pressure on electricity generation by increasing the risk of power outages due to excessive peak cooling and heating requirements. Various issues on building thermal comfort are being evolved and discussed in review articles. However, there are few articles that review the current condition of adaptive thermal comfort studies and the potential for energy savings in residential buildings. Therefore, the aims for this paper are to: identify comfort temperature ranges in residential buildings, investigate the correlation of comfort temperature with indoor and outdoor temperatures with the aid of ‘comfort threads’, and clarify the effect of adaptive measures on residential energy saving potential. This study obtained a large variation of residential comfort temperatures, which mostly depend on the climate and operation modes of the building. ‘Comfort threads’ explains that people are adapting to a large variation of indoor and outdoor temperatures and the wide range of comfort temperature could provide significant energy savings in residential buildings. This review provides insight on and an overview of thermal comfort field studies in residential buildings.

Comparative study of indoor thermal environment and human thermal comfort in residential buildings among cities, towns, and rural areas in arid regions of China

Most thermal comfort studies classify towns as rural areas and compare them with cities, dismissing the unique thermal characteristics of towns. A comparative study on thermal comfort in cities, rural areas, and towns based on their original definitions is required. This study aims to determine the differences between indoor thermal environment and human thermal comfort in residential buildings in cities, towns, and rural areas. This four-month investigation was conducted in Bayannur City using a survey with 141 participants. The survey responses were combined with environmental measurements, and the data analysis showed that the participants’ clothing insulation was distributed over a wider range for towns (0.3–0.9 clo) and rural areas (0.9–1.5 clo) than for cities (0.3–0.6 clo). The acceptable operative temperature ranges of city, town, and rural area residents were 20.9–28.0, 17.7–23.3, and 15.1–21.6 ℃, respectively. Although the operative temperature of residential buildings in those areas differed by 5–10 °C, all participants expected a warmer indoor thermal environment. City residents who can adapt to varying conditions can restore thermal comfort more easily than town and rural area residents.

EFFECT OF WINDOWS CONFIGURATION IN WALL PANELS ON ROOM TEMPERATURE IN NATURALLY VENTILATED RESIDENTIAL BUILDINGS IN ASABA, NIGERIA

The type of windows configuration in residential building influences the amount of radiation that enters into the interior occupied spaces. The level of comfort or discomfort experienced within the buildings is thus hinged on the type of window configuration in the building facade. There are different window configurations in the study area, and the environmental designers or architects use any of the window type in spite to its implication on thermal comfort aspect of the building. Physical measurements and questionnaire were conducted in naturally ventilated residential buildings, to investigate the effect of window configuration in wall panels on room temperature in naturally ventilated residential buildings in Asaba, Nigeria. The effect of indoor room temperature on occupant thermal comfort was examined. Different window configurations commonly used in residential buildings in the study area are sliding, projected, casement, casement-with-vent, and louvre window. The results show that appropriate window configuration in wall panels can provide comfort level on room temperature. Recommendations were made to improve thermal comfort in residential buildings using window configuration with PMV value of 4.5 or less which are casement with vent, louvre and casement windows in naturally ventilated residential buildings.

Thermal comfort optimization through bioclimatic design in Mediterranean cities.

Background: Bioclimatic design is an approach based on local climate which improves thermal qualities and indoor comfort. Buildings follow this process to minimize negative effects on the environment. However, this approach is still not suitable in developed countries. This study aims to investigate Mediterranean local bioclimatic strategies' impact on thermal comfort efficiency in housing, by examining architectural elements and treatments. Methods: We adopted a descriptive, analytical, and comparative methodology, complemented with a software simulation, within a qualitative and quantitative approach. Investigation and methodological tools were based on technical information including plans, elevations, photos, and documentation. The approach consisted of multiple stages: a literature review interpreting the concept of bioclimatic design, as well as thermal comfort variables and common Mediterranean building features. Moreover, the paper showcases three examples of successful Mediterranean passive houses. Furthermore, the paper presents a case- studyhouse in Alex West, Alexandria, designed in the Mediterranean Revival style. Results: The results showed that the most influencing building features on thermal comfort were the low-pitched roofs and the top chimney, which achieved 12.6% and 5% improvement in the summer and 13% and 6.8% in winter, respectively. The pergola and porch elements barely had an effect when placed on the northern façade. However, on the southern façade, a positive contribution in the summer by 1.4% and 3.4% respectively were reported, but a slight negative impact in winter by 0.5% and 2% respectively. Conclusions : We examined the impact of common Mediterranean building features , and compared thermal comfort results between case-study houses. Features focusing on passive design for cooling rather than heating, allowing wind flow for maximized natural ventilation, using ventilated pitched roof spaces, using sun shading elements in the proper facades and angles, help passive thermal regulation. The study proposes recommendations for optimizing thermal comfort in residential buildings in Alexandria, Egypt.

Thermal Network Model for an Assessment of Summer Indoor Comfort in a Naturally Ventilated Residential Building

Costs of cooling installations cause them to be very rarely used in residential buildings in countries located in heating-dominated climates, like Poland. Hence, there arises the need to assess indoor thermal comfort during summer and to indicate ways to reduce possible overheating. This paper presents an attempt to use the thermal network model of the building zone of EN ISO 13790 to assess indoor operative temperature during four warm months from June to September. The model of the naturally ventilated single-family residential building located in central Poland was used. Performed calculations for the base case resulted in 38 and 63 days within the comfort zone at 80% acceptance level in a total of 122 days in the analyzed period for EN 15251 and ASHRAE standards, respectively. Use of external shading on windows and the roof with lower solar absorptance resulted in 46 and 70 days with acceptable conditions, respectively. Further application of night ventilation resulted in the 38 and 63 days, respectively. From the considered solutions in Polish climate conditions, windows shading seems to be the most efficient solution when controlling indoor comfort in residential buildings with no cooling system. A comparison of hourly operative temperature from that model with the detailed simulation in EnergyPlus showed a strong correlation with R2 = 0.934.

Light, Air, and (No) Sun. Negotiating Illuminance, Ventilation and Insolation Through Architectural Form To Achieve Energy-Efficiency and Comfort in Residential Buildings in Very Hot Climates: Two Case Studies from Muscat, Oman

The discourse on energy-efficient buildings tends to shift out of the realm of architecture and into engineering and programming. In the latter disciplines, sophisticated solutions are developed and introduced to the green building industry. However, such solutions require financial and technical capacities that are only found in technologically highly developed countries. In developing countries and their ever-growing metropolises, a much more robust approach seems appropriate. This paper explores how the energy-demand for creating comfortable interior environments in very hot climates can be significantly reduced by promoting simple and straightforward architectural means. It seeks to relocate the discourse back into the realm of design, where less costly, more feasible and long-lasting solutions can be found. The paper presents two case studies of residential architecture in Muscat, Oman. Through simulations of solar insolation as well as daylight studies, it shows how architectural form can respond to two solar phenomena - heat and light – in such a way that insolation on glazed facades is minimized, while illuminance of interiors is optimized. It claims that this can lead to a new regional architectural idiom that puts the famous modernist credo on its head by stating that energy-efficient buildings in a hot climate zone require “light and air, but no sun”.