Improve Building Performance Research Articles

Impact of occupant related data on identification and model predictive control for buildings

Model predictive control (MPC) has shown potential in improving building performance but is bottlenecked by the difficulty in constructing control-oriented models. The challenge lies in evaluating the sufficiency of the model and the data usage beforehand. This paper bridges the knowledge gaps in the interactions between data requirements, model quality, and control performance by integrating real-world measurements and simulation-based experiments. The data usage related to occupancy and Internal heat gain (IHG) was studied considering its importance and the absence of consensus in the literature. Varying occupant-related data sources were tested as RC model inputs, including none, schedule, electricity consumption, CO2 ppm, and ideal measurement. Combinations of model inputs and complexities were examined for prediction and control in an office, a classroom, and multi-zone offices on one floor. The results indicated that the usefulness of data is jointly affected by three factors: measurement suitability, model complexity, and modeling purpose. Given the adequate model structure, satisfying prediction and control performance was achieved in offices with no detailed measurement. Meanwhile, electricity and CO2 were needed together to capture the IHG influence and realize the good performance for classrooms. The experiments also uncovered the heterogeneous requirements on models from traditional prediction tests and the control tasks. Lower prediction error did not always mean better control. More importantly, we provided the first quantitative demonstration of the complementary relationship between model adequacy and data informativeness with respect to different purposes. This study advocates the pioneering idea of sparse data usage and parsimonious modeling, which promotes the actual application of MPC in buildings by guiding control-oriented model development.

Real-world implementation and cost of a cloud-based MPC retrofit for HVAC control systems in commercial buildings

Many businesses are looking for ways to improve the energy and carbon usage of their buildings, particularly through enhanced data collection and control schemes. In this context, this paper presents a case study of a food-retail building in the UK, detailing the design, installation and cost of a generalisable model predictive control (MPC) framework for its Heating, Ventilation and Air Conditioning (HVAC) system. The hardware/software solution to collect relevant data, as well as the formulation of the MPC scheme, is presented. By utilising cloud-based microservices, this approach can be applied to all modern building management systems with little upfront capital, and an ongoing monthly cost as low as $6.39/month. The MPC scheme calculates the optimal temperature setpoint required for each Air-Handling Unit (AHU) to minimise its overall cost or carbon usage, while ensuring thermal comfort of occupants. Its performance is then compared to the existing legacy controller using a simulation of the building’s thermal behaviour. When simulated across two months the MPC approach performed better and achieved the same thermal comfort for a lower overall cost. The economic optimisation resulted in an energy saving of 650 kWh, with an associated cost savings of $240 (an improvement of 1.7% compared to the baseline), while the carbon optimisation gave negligible CO2 savings due to the inability of the building to shift heating to low-carbon periods. Findings from this study indicate the potential for improving building performance via MPC strategies, however the level of impact will depend on specific building attributes.

Bibliometric Analysis of Post-Occupancy Evaluation (POE): Current Status, Development, and Future Research Directions

The application of post-occupancy evaluation (POE) has increased recently, owing to the methodology's ability to improve building performance. However, the procedures employed vary depending on the building's suitability and category. Therefore, this study aims to provide a comprehensive survey to explore the state-of-the-art POE research. Bibliometric analysis was used to retrieve 381 POE publications from the Scopus database between 1979 and 2020. VOSviewer software was applied for the visualization and scientific mapping of literature. The study helps researchers understand by offering comprehensive data about the most literate nation contributions, publications' significant sources, and devoted authors to POE publications. The findings revealed that the United States, the United Kingdom, and China had rendered the three most literature contributions; Building Research and Information were the top publication's significant source titles, and Hassanain, M.A. is incredibly devoted to POE publication. Research hotspots in the POE focus on building performance, architectural design, and sustainable development. The primary themes in POE concentrate on comfort, sustainability, performance, design and criteria. Future research should emphasize that POE is used on heritage buildings to ensure that these buildings perform well for sustainability. It will significantly value the people involved in the design, construction and also conservation practice.

External shading form-finding: simulating daylighting and dynamic view access assessment

Providing sufficient daylight and view access to the outdoors is crucial to creating a productive work environment and ensuring employees’ wellbeing and mental health in offices. To these aims, determining an optimum shading form can be challenging for designers. This study applied an ‘external shading form-finding’ and a novel ‘dynamic view access assessment’ method to find the optimum shading devices from 723 shading systems. Each system contains a typical louvre blade with two equidistant shading devices. These were externally fixed in front of a south-facing window with a dynamic interior blind, and were tested across three window-to-wall ratios. Optimum forms were selected according to LEED v4 daylight needs and unobstructed views. The results indicate that these proposed methods have the potential to support decision-making related to shading design, helping designers and architects to study the view quantitatively and combine its results with daylight assessment leading to improved building performance, employee mental health and wellbeing.

Design of Integrated Electrochromic-Photovoltaic Technology for Smart Windows to Improve Building Performance and Energy Efficiency: A Material Approach

Energy and climate problems that occur encourage the intensification of energy use efficiency, one of which is in buildings. The building sector is the largest contributor to energy consumption when compared to other sectors due to the need for comfort in life, including to regulate air temperature, ventilation, and artificial lighting. Window innovation as a building component leads to adaptive smart windows technology that has energy saving features. The use of these windows is attractive because they are designed to adapt to changing environmental conditions to minimize large heat losses by adjusting their transmissivity and conductivity. Various types of smart windows have developed, one of which is electrochromic technology as dynamic glass technology which has been widely used as smart windows in commercial buildings. Several studies have shown that its use in buildings has been shown to save energy consumption in buildings through the HVAC and lighting aspects. However, in today's technology, its performance still requires external power to adjust their optical conditions. Therefore, the innovation in developing electrochromic smart windows technology that is integrated with photovoltaic technology is an interesting thing to do. The combination of the electrochromic solution with photovoltaic Si-TFSC placed on a glass substrate provides promising optical performance and energy benefits. The integration of electrochromic and photovoltaic devices provides better efficiency in energy saving, because photovoltaic and electrochromic devices can achieve electrochromic layer discoloration without an external power source. Given the photoelectric and optical modulation properties of electrochromic photovoltaic windows that can function as solar cell modules as well as powered smart windows on their own, this technology has a major advantage in applying sustainable energy to buildings. In its application in buildings, to improve device performance, the control system can be applied by adjusting environmental conditions according to the sensor system readings to obtain better device performance.

Global Prospects, Advance Technologies and Policies of Energy-Saving and Sustainable Building Systems: A Review

Automation, modernization, economic development and global progress depends on efficient extraction and utilization of energy. Power generation by burning fossil fuels makes various adverse impacts on the environment. Additionally, the worldwide fossil fuel reserve is limited and depleting very fast. Hence, efficient energy usage and savings are crucial to address the environmental issues to ensure sustainable development. Buildings, both commercial and residential, represent a major energy consumption sector. Approximately 40% of the total energy is reportedly consumed in the building sector. Worldwide building energy consumption, performance measuring systems and best practices, energy-saving techniques and policies are reviewed and summarized in this article. Underfloor air distribution, double-glazed windows, use of highly efficient electric motors and variable speed drives may play a great role in reducing building energy consumption. In the UK, the application of double-glazed windows in commercial buildings can save 39–53% energy. The proper maintenance of a building’s central heating system can save up to 11% energy. The automatic HVAC control system can reduce up to 20% of the building’s total heating load. Proper utilization of a VSD system in motor and building performance optimization by an ANOVA tool also proved instrumental in saving energy. Apart from this, the building codes of different countries also help to improve building performance by reducing energy consumption. This study will help building researchers and policymakers to make a framework for sustainable, green building.

Whole building life cycle assessment at the design stage: a BIM-based framework using environmental product declaration

PurposeWhole building life cycle assessment (WBLCA) is a key methodology to reduce the environmental impacts in the building sector. Research studies usually face challenges in presenting comprehensive LCA results due to the complexity of assessments at the building level. There is a dearth of methods for the systematic evaluation and optimization of the WBLCA performance at the design stage. The study aims to develop a design optimization framework based on the proposed WBLCA method to evaluate and improve the environmental performance at the building level.Design/methodology/approachThe WBLCA development method is proposed with detailed processes based on the EN 15978 standard. The environmental product declaration (EPD) methods were adopted to ensure the WBLCA is comprehensive and reliable. Building information modeling (BIM) was used to ensure the building materials and assembly contributions are accurate and provide dynamic material updates for the design optimization framework. Furthermore, the interactive BIM-LCA calculation processes were demonstrated for measuring the environmental impacts of design upgrades. The TOPSIS-based LCA results normalization was selected to conduct the comparisons of various building design upgrades.FindingsThe case study conducted for a residential building showed that the material embodied impacts and the operational energy use impacts are the two critical factors that contribute 60–90% of the total environmental impacts and resource uses. Concrete and wood are the main material types accounting for an average of 65% of the material embodied impacts. The air and water heating for the house are the main energy factors, as these account for over 80% of the operational energy use. Based on the original WBLCA results, two scenarios were established to improve building performance through the design optimization framework.Originality/valueThe LCA results show that the two upgraded building designs create an average of 5% reduction compared with the original building design and improving the thermal performance of the house with more insulation materials does not always reduce the WBLCA results. The proposed WBLCA method can be used to compare the building-level environmental performances with the similar building types. The proposed framework can be used to support building designers to effectively improve the WBLCA performance.

A thematic review on Prevention through design (PtD) concept application in the construction industry of developing countries

The life cycle of the building or any other type of structure comprises the stages of planning, design, construction, operation, and maintenance until demolition. The life span of each stage is different and the operation and maintenance stages account for the longest period in a building’s lifespan. On that account, building performance after its completion is foremost to corroborate the Prevention through Design (PtD) concept. PtD, also known as safety by design or design for safety, is the concept of reducing the potential occupational hazards beforehand during the design stage. The developing countries have also started practicing this concept. A systematic review has been used as a methodology to overview the applications of this concept in the construction industry in developing countries. The study identified 218 peer-reviewed articles from a keyword search in online databases. The search process for the articles was filtered by inclusion and exclusion criteria. In the result, a total of 16 articles were identified. The ATLAST.ti 8 was utilised to conduct the theme analysis review of the final articles. A conceptual framework of cluster patterns on the PtD applications for construction industry in the developing countries has been developed. The framework is themed into 5 main pattern clusters: (1) Building life cycle, (2) Legislation, (3) Design, (4) Building Information Modelling (BIM), and (5) Project management (PM); from 10 clusters: (1) Law and regulations, (2) Guidelines, (3) BIM, (4) Architectural design, (5) Planning stage, (6) Construction stage, (7) Operation and maintenance stage, (8) PM, (9) Designer’s knowledge and (10) Designer’s attitude. Hence, this paper incorporates the very latest information on PtD concept application in the construction industry of developing countries. The main finding of this paper reveals that the PtD concept is vital to enforcing the legislation to improve building performance and reduce the possible hazards that lead to accidents during the whole life cycle of a building.

Defect management of hospital buildings

Healthcare organisations are increasingly recognising the need to improve building performance in order to improve health care delivery, profits, and to reduce penalties. Hospital maintenance organisations are under constant pressure to plan maintenance work due to a shortage of funds on account of huge catalogues of defects in hospital buildings. While investments in hospital building maintenance are increasing, the requirement to increase building performance and user satisfaction is also increasing. The nature of building faults and the factors that influence hospital building maintenance management in Malaysia were explored. Primary data were collected through structured interview techniques involving six hospital maintenance organisations. According to the results of a survey interview involving six hospitals, water seepage, cracks, peeling paint, broken ironmongery, pipe leakage, damaged plasterboard, and discoloured paint are all widespread in hospital structures, according to the results of a survey interview involving six private and public hospitals. The key aspects that determine the maintenance management practise of hospital buildings are user attitudes, misuse/abuse, weather, and bad maintenance practice. The data revealed that hospital building users are demanding improved building performance through enhanced maintenance management service delivery. Implicit in the findings of this research is the lack of effective maintenance organisations. It is necessary to reorganise the hospital's maintenance organisations. From an ontological standpoint, the main findings of this study are generalizable to other hospitals and building typologies in and outside of Malaysia.

Effectiveness of Damping Devices on Coupling Beams of 15-story Building Based on Nonlinear Analysis Procedures

In recent years, damping device has been experimentally studied to replace diagonally reinforced coupling beams, to mitigate rebar congestion problem. This study focuses on evaluating the effectiveness of various damping devices in a high-rise building. Type of damping devices evaluated are Viscoelastic Damper (VCD) and Rotational Friction Damper (RFD), with study case of a 15-story reinforced concrete apartment building with a dual system (column-beam and shear walls). The analysis used is a nonlinear time history analysis with 11 pairs of ground motions matched to the Indonesian response spectrum based on ASCE 41-17 and ASCE 7-16. In this analysis, each damper will be varied with a different position, namely the first model, the damper will be installed on the entire floor and in the second model, the damper will be installed on the 5th floor to the 9th floor, which is the floor with the largest drift. The results show that the model using both dampers increase the level of structural performance globally and locally in the building, reducing the level of damage to the structural elements. But between the two dampers, the coupling beam that uses RFD is more effective than using VCD in improving building performance. The damper on the coupling beam has a good role in dissipating earthquakes and in terms of ease of installation.

A new method of evaluating energy efficiency of public buildings in China

Traditional building energy evaluation methods usually adopt a single energy use indicator as the benchmark. However, such single-indicator based methods often lead to a paradox that switching off building service equipment or systems is equivalent to energy saving. To avoid such paradox for a more pragmatic and comprehensive evaluation of building energy use, this paper aims to establish a robust evaluation model of the operational energy efficiency for public buildings by coupling the analytic hierarchy process (AHP) and fuzzy comprehensive evaluation (FCE). Firstly, 23 quantitative indexes and 7 qualitative indexes are extracted from existing building energy codes/standards in the input-output perspective of energy performance evaluations for public buildings. The AHP is then used to determine the weight of each index based on a proposed index correction method, which extends the range of applicability of the index system. Finally, a three-level comprehensive evaluation model is established for the operational energy efficiency of public buildings. Furthermore, a case study is conducted on a typical office building to validate the evaluation results with the proposed model. The case building achieves an overall score of 84.9 at a “Good” level, and corresponding recommendations are made for further improving building performance indexes. The proposed method is of great significance to developing building energy efficiency assessment systems and guidelines in China and over the world.

Section 3: Preliminary Material

• Preface It is our privilege to present the proceedings of the two-day online Conference entitled “Indo-European Conference on Sustainable Materials, Environment and Construction (COSMEC-2021)”. The Conference was held virtually considering COVID – 19 pandemic, ensuing gathering and travel restrictions in the nation and worldwide. Yet, despite the issues, the virtual COSMEC 2021 took place on 23rd and 24th September 2021 and attracted a more significant number and diverse mix of attendees than it would have done as per expectations. The Organizers, i.e. Chandigarh University, Mohali, India, which runs the event, seek to promote international collaborations in Research and Innovation. The Conference was delivered through ZOOM Cloud Meeting technology. More than 150 extra individuals signed up to COSMEC-2021 over the guests, presenters, and invited attendees because of easier online access. Collectively more than 300 people attended from 15 countries. The Conference had delegates, participants, and attendees from Tanzania, South Africa, Kazakhstan, Russia, Afghanistan, Bangladesh, Bhutan, Nepal, and European countries — some of whom might not otherwise have come because of the distance and time constraints in traveling. The Conference consists of six sessions, including inaugural and valedictory. Prof M. Dana Oprisan from EPF Graduate School of Engineering, France graced the plenary Session along with Dr. Adarsh Pal Vig, Chairman, Punjab Pollution Control Board (PPCB), Punjab, India. Furthermore, six Keynote addresses were given by researchers and scientists from Indian Institutes of Technology (IIT’s), National Institutes of Technology (NIT’s), and National Institute of Technical Teacher Training & Research (NITTTR), Chandigarh. Overall, 80 paper presentations were delivered by authors in four technical sessions of the Conference based on specializations. Authors were facilitated with 15 minutes to present their papers, followed with 5 minutes of discussion and query session. The paper presentation and discussion emphasized incorporating sustainable materials, their environmental impact assessment, and compatibility with construction. The national and international research scenario on sustainable design seeks to reduce negative impacts on the environment and the health and comfort of building occupants, thereby improving building performance. The primary objectives of sustainability are reducing the consumption of non-renewable resources, minimizing waste, and creating a healthy environment. Consequently, interdisciplinary and integrated innovations have resulted in numerous smart solutions. This event provided a forum for researchers from different scientific and engineering fields to deliberate and collaborate at national and international levels for translating research into intelligent possibilities to make human life better.Chandigarh University, Gharuan, the leading university in research and Innovation in India, sponsored this Conference. This Conference provided an opportunity for in-depth technical discussions and exchange of innovative ideas on a wide range of possibilities to explore the potential of their applications in industry and society. Moreover, young researchers were exposed to emerging trends and research areas that have significant technical and scientific importance for sustainable development.List of Conference photographs, Sponsor or funding acknowledgements, Lists of committees/participants are available in the pdf

Engaging UK repair–maintain–improve practitioners in improved building performance

PurposeTo improve building performance and meet statutory carbon reduction targets, a radical transformation of existing UK building stock is needed. Much previous research on building performance has focussed on large-scale construction. However, retrofit of existing housing stock – which will contribute the majority of the requisite efficiency improvement – is carried out by practitioners in the repair–maintain–improve (RMI) subsector. These practitioners are the sole traders and micro-firms who constitute two-fifths of employment in the construction sector. The study aims to examine the factors influencing these practitioners in RMI work to understand how better to engage them with improved building performance.Design/methodology/approachA total of 31 semi-structured interviews were conducted with RMI professionals from around the UK and analysed using template analysis.FindingsThe analysis identified capabilities of the practitioners who influence building performance, including knowledge and co-ordination of people and resources; opportunities including state action and customer demand; and motivations including pride in work, customer care and satisfaction, maintaining a viable business and working relationships.Research limitations/implicationsThe participants were a small, mixed group in terms of firm size and specialisation. The qualitative approach adopted provided detailed insights but does not make claims for statistical generalisability or representativeness of the findings. Future work could look to extend the findings with a statistically representative survey.Practical implicationsFor a successful transition to high standards of building performance, modelling is not enough. Initiatives are needed to address the multiple factors which determine engagement in energy-efficient retrofit: capacities, opportunities and motivations. The desire of RMI practitioners to meet customer expectations could be used to develop pragmatic building performance evaluation, guided by householder satisfaction criteria.Originality/valueThe study examined the attitudes and experiences of an under-researched sector who are essential to the delivery of improved building performance. This study makes a novel contribution by applying an established psychological model of behaviour change, the capability, opportunity, motivation – behaviour model, for the first time in this domain.

A review of applied methods of optimization in steel structures

AbstractRecent dazzling progress in computer science and stringent requirements of the design of “more optimized” buildings put forwards the study and research of the various optimization methods in the building sector. This study presents a comprehensive review of the state‐of‐the‐art and the most applicable algorithms applying computational optimization to Steel buildings and different steel design problems. Four different algorithms including Neural Network, Bee and Bat‐Inspired algorithm and Metaheuristic Optimization algorithm have been studied with emphasized on the application of these methods in steel structures. Algorithm Key points are reviewed with more details including configuration of the algorithms and control of building systems, besides particular attention on accuracy and capability of them to be converged as an optimized solution. From different convergence rate, number of unknown parameters and boundaries of solutions It can be concluded that in near future researches should be oriented towards improving the efficiency of the most effective search techniques and realistic approximation methods especially in large‐scale building optimization problems; and reducing time with increasing accuracy for such activities. Further effort should be required to quantify the robustness in optimal answers so as to improve building performance.

The autonomous robotic environmental sensor (ARES)

Measurement of thermal comfort in the indoor environment enables making adjustments to building design and operations to improve building performance. Methods of measurement tend to be tedious and expensive, requiring several expensive sensors to be mounted in the building. In this paper, we propose the Autonomous Robotic Environmental Sensor (ARES), a custom-designed omniwheel mobile robot retrofitted with several sensors capable of autonomously taking measurements of the indoor environment at multiple positions, reducing the number of sensors, amount of labor required, and cost. A Sliding Mode Controller (SMC) is designed and applied to the robotic platform, and positional accuracy is verified, allowing for highly accurate movement to ensure environmental measurements occur at known positions. Wind velocity, air temperature, and relative humidity data collected by the ARES platform in a laboratory environment for 24 hours is analyzed, providing insight into the thermo-fluid variables in the room and the room’s predicted thermal comfort.

Developing and Applying a Model for Evaluating Risks Affecting Greening Existing Buildings

Improving building performance through reducing negative environmental impacts can be achieved by greening existing buildings (GEB), which is considered a very important sustainability process. Due to the risky and uncertain nature of the process of GEB, a growing amount of attention should be given to eliminating the effects of risks on GEB. This research aims to identify most expected risk factors related to GEB, as well as to evaluate their effects through calculating risk factor characteristics, such as risk factor presence (RFP), impact on the GEB process (IGEB), and impact on building performance in the long run (IBP), as new indices describe these risks. Sixty-six risk factors were categorized in seven risk groups related to the economic aspect, social aspect, environmental aspect, managerial aspect, sustainability operation, sustainable design, and renovation. Moreover, a fuzzy model for risk analysis was developed to combine the multi-effects of the aforementioned three risk factor characteristics in one index representing the risk factors’ overall importance. The model was applied and verified for data collected in Saudi Arabia. The results of this study showed that the most important risk group is the greening process of environmental control, while the least important is the greening process of renovation and construction. Using the proposed model improved the results of evaluating risks affecting GEB through merging the multi-effects of risk factor characteristics. The results and analysis proved that the most important key risk factors were environmental in nature. An intricate relationship of the impacts on the GEB process and building performance with the overall importance of the risk factors was clearly found. The decision makers who deal with greening projects in Saudi Arabia should be aware of the key risks identified in this study. The proposed methodology and model can be easily applied to other countries to help decision makers in evaluating their GEB projects, as well as comparing more greening projects based on risk analysis.

Holistic energy efficient design approach to sustainable building using monitored energy management system

Building sector focuses on surpassing challenges linked to energy efficiency and mitigation measures related to greenhouse gas emissions, in consequence, it needs to improve building performance in the interest of decreasing impact over environment. Buildings with reduced long-term operating cost, environmental-friendly and moderate construction costs can be achieved only by multi-object optimization and cross-disciplinary analysis, embodying a holistic approach. Following the main principles of the holistic sustainable design approach, the paper presents a sustainable experimental modular laboratory involving various strategy in regard with sustainable building, as resource, cost and material efficiency, health and well-being, environmentally conscious design, life cycle design, modular design, reusable/recyclable element, environment-friendly demolition method, safety design, consideration of life cycle cost, materials cost and waste disposal cost. Besides the installation of renewable energy sources and conservation of energy, the holistic construction of laboratory included also an integrated design with consideration for technology, operation and maintenance, which involved the implementation of a monitored energy management system. The system provides an accurate overview of the building’s performance during operational phase. Although the monitoring is still in an incipient phase, recordings showed promising results regarding the behaviour of recycled-PET thermal wadding used for insulation and indoor comfort conditions.

A comprehensive comfort assessment method for indoor environmental quality in university open-plan offices in severe cold regions

This paper presents a comprehensive comfort assessment method for indoor environmental quality in university open-plan offices (UOROs) in severe cold regions based on the combination weighting method. The questionnaires for the fuzzy analytic hierarchy process (FAHP) method were firstly collected from 405 experts to obtain the subjective weighting scheme of UOROs. Then, the field measurements of four environmental factors of 22 UOROs were conducted and the corresponding 1352 questionnaire surveys on the subjects’ comfort were collected. The relationships between four comfort factors and indoor environmental parameters were obtained from the field studies, and the objective weighting scheme was calculated using the entropy method (EM). Based on the game theory, the combination weighting scheme was given via integrating the results of the FAHP method and EM. The comprehensive comfort index for UOROs was finally provided by combining factor weights and fitting formulas, and the rationality and correctness of the method were demonstrated via experimental verification. Furthermore, the comparison of the weighting schemes between this study and other studies was discussed and the results revealed that the requirements of researchers for the sound environment were higher than normal office workers. The comprehensive comfort assessment method in this study can help designers and users to improve building performance by adjusting indoor environmental parameters and also make them better balance the relationship between human comfort and energy use.

Influential aspects on melting and solidification of PCM energy storage containers in building envelope applications

ABSTRACT Phase change materials (PCMs) incorporated building envelope for thermal energy storage (TES) considerably enhances building thermal energy and improves indoor comfort. Amongst other methods, macroencapsulation provides a flexible and efficient PCM utilization among practical incorporation methods during a long time of service. Nevertheless, there is still arguement regarding PCM thermal performance during melting and solidification phases due to macroencapsulation containers, not to mention PCM’s poor thermal conductivity. A brief overview of possible practical integration methods of PCMs with building elements is presented along with the main advantages and drawbacks in this work. This is followed by the popular incorporation techniques in building applications giving special attention to the macroencapsulation method and its role in improving building performance. The main influential aspects of macroencapsulated PCM performance during the melting and solidification, namely the shape, material type, compatibility with PCM type, and enhancement methods of encapsulation containers, are highlighted and discussed. We believe that this work analysis and conclusions provide a clear understanding of the main trends and gaps in this research area for further investigation and optimization studies by researchers, engineers, and developers.

Assessment of technological performance of extruded earth block by adding bottom biomass ashes

The search for more sustainable construction materials has led researchers to reconsider ancient techniques, such as earth-based construction materials (EBCMs). These have been lately highlighted as a feasible way of reducing environmental footprint and improving building performance. EBCMs are commonly divided into monolithic and brickworks solutions but these last are specially promoted due to the advantage of automation techniques which contribute to guarantee constant quality and economical production. However, hygroscopic and mechanical behavior have been constantly pointed out as major barriers for extending their use. The addition of fibres and/or polymers incorporation or the stabilization by means of cement or alkali activation, among others, have tried to face this issue but environmental and economic impacts have frequently called into question these findings. Thus, with the aim of developing a feasible and environmental friendly EBCMs, this paper assesses the impact of manufacturing EBCMs by replacing up to 20 % of soil with biomass bottom ashes (BBA). Industrial procedures were followed for developing samples which were not stabilized by any additive. It has been concluded that the addition of BBA barely influences mechanical properties which range from 2.5 MPa to 3.8 MPa. Conversely, thermal conductivity and density are slightly reduced which leads to lighter materials and higher insulation values. Besides, specific heat is slightly increased which may improve overall building energy performance. Finally, it has been demonstrated that water resistance and toxicity comply with mandatory threshold values.