Thermal and Vibration Comfort Analysis of a Nearly Zero-Energy Building in Poland

Investigation of Materials for Enhanced Vibrational Insulation in Ground Structures Using Concrete Mixtures: A Case Study of Rubber Aggregate Addition

The reduction of vibrations in concrete has been a topic of discussion among scientists. This article presents research on designing concrete mixes for constructing ground barriers with enhanced vibration isolation using waste materials. This study discusses the design of concrete mixes for the construction of concrete partitions with increased vibration isolation, using the polish standards. The experiments were conducted at the Laboratory of Building Materials Engineering at the Cracow University of Technology as part of the project entitled "Innovative construction of vibration-insulating barriers to protect the environment from transport vibrations and similar sources". The concrete composition utilized blast furnace cement CEM III/A 42.5 N, with mineral and chemical additives. Recycled rubber aggregate from used tires was employed to enhance vibration isolation. Measurement results demonstrated the effectiveness of the concrete in dampening vibrations, confirming its suitability for practical use.

Raw and Pre-Treated Styrene Butadiene Rubber (SBR) Dust as a Partial Replacement for Natural Sand in Mortars

The circular economy (CE) is widely known for its emphasis on reducing waste and maximizing the use of resources by reusing, recycling, and repurposing materials to create a sustainable and efficient system. The CE is based on 3R-reuse, reduce, and recycle. The aim of this article is to use styrene butadiene rubber dust (SBR) in building material, constituting secondary waste in the production of SBR, which is currently disposed of as landfill. SBR is partly intended to replace the natural raw material sand. The purpose of the final material is to use it for its light weight, insulating properties, or ability to absorb vibrations and sounds. Various shares of SBR dust in mortars were tested. Some of the mortars used SBR thermal pre-treatment at temperatures of 200, 275, and 350 °C. The strength and SEM results are presented. The best pre-treatment for SBR dust is thermal treatment at 275 °C. The maximum usage of rubber dust with thermal treatment is 60% as a sand substitute. The novel finding of this study is the possibility to use more than 30% rubber dust (as a substitute for sand) thanks to pre-treatment, whereby 30% is a common maximum ratio in mortars.

Thermal Comfort—Case Study in a Lightweight Passive House

Saving energy while maintaining a high-quality internal environment is an increasingly important scientific and technological challenge in the building sector. This paper presents the results from a long-term study on thermal comfort in a passive house situated in the south of Poland. The building was constructed in 2010 with the use of prefabricated, lightweight technology. The main energy source is a ground source heat pump which powers the floor heating and DHW. The building is also equipped with a mechanical ventilation system with heat recovery and a ground source heat exchanger. A lightweight building structure which has active systems with limited capabilities (especially for cooling) is a combination which increases the difficulty of maintaining a proper inner environmental condition. Extensive experimental investigations on hygrothermal performance and energy use have been carried out in the building for several years. The measurement results, such as inner air temperature and humidity, as well as the inner surface temperature of partitions, could be directly used to determine basic thermal comfort indicators, including PMV and PPD. Any missing data that has not been directly measured, such as the surface temperature of the windows, floors, and some of the other elements of the building envelope, have been calculated using WUFI®PLUS software and validated with the available measurements. These results are not final; the full measurement of thermal comfort as an applied methodology did not consider human adaptation and assumed constant clothing insulation. Nevertheless, in general, the results show good thermal comfort conditions inside the building under research conditions. This was also confirmed via a survey of the inhabitants: 2 adults and 3 children.

Potential Applications of 5G Network Technology for Climate Change Control: A Scoping Review of Singapore

Climate change is one of the most challenging problems that humanity has ever faced. With the rapid development in technology, a key feature of 5G networks is the increased level of connectivity between everyday objects, facilitated by faster internet speeds with smart facilities indicative of the forthcoming 5G-driven revolution in Internet of Things (IoT). This study revisited the benefits of 5G network technologies to enhance the efficiency of the smart city and minimize climate change impacts in Singapore, thus creating a clean environment for healthy living. Results revealed that the smart management of energy, wastes, water resources, agricultures, risk factors, and the economy adopted in Singapore can remarkably contribute to reducing climate change, thus attaining the sustainability goals. Hence, future studies on cost-effective design and implementation are essential to increase the focus on the smart city concept globally.

Building Energy Performance Analysis after Changing Its Form of Use from an Office to a Residential Building

Lowering energy consumption is one of the most important challenges of the modern world. Since the construction sector accounts for 40% of total energy consumption worldwide, the Parliament of the European Union has developed a Directive, according to which all newly designed and thermally upgraded buildings should meet the requirements of almost zero energy demand (nZEBs) from 1 January 2021. At the same time, in Poland, but also in many other countries in the world, there is a growing oversupply of office space in large cities with a simultaneous increase in demand for apartments, which is caused, among other things, by the increase in the share of remote work and the COVID-19 pandemic. Consequently, this is forcing owners to change the use of buildings from office to residential. This article analyses the possibilities of changing the function of an office building to a multi-family residential building. For both functional solutions, a comparative energy analysis was carried out, taking into account different work schedules and the requirements for new buildings with zero energy demand. The analyses have shown that changing the form of use of an office building to a multi-family building without significant financial and technical costs is possible. On the other hand, the reverse change of the form of use is much more difficult and, in many cases, practically impossible. Due to the fact that many offices are now multinational corporations, this issue is global.

Alternative Ways of Cooling a Passive School Building in Order to Maintain Thermal Comfort in Summer

The heatwaves that have affected our civilization in recent years pose a serious threat to the environment as well as the proper functioning of our bodies. Schools are facilities with specific microclimatic requirements. Thermal conditions in educational buildings are decisive for the stimulation and efficiency of the learning process, as well as the interaction of students. Based on the measurements of thermal comfort carried out in the school building, with the energy standard of a passive building, it can be observed that in schools with very low energy consumption, the problem of interior overheating may occur in the summer months. In this paper, an attempt was made to search for alternative passive measures allowing for the required indoor microclimate conditions to be obtained. Such solutions are in line with the spirit of the European energy policy and sustainable development. A model of the school under study was created using the Design Builder simulation program. The role of mechanical ventilation and the possibility of night ventilation in reducing discomfort were examined. Consideration was given to the justification of using expensive heat pump installations with a ground heat exchanger to reduce overheating in summer. The application of the adaptive approach to the assessment of thermal conditions and the acceptance of limited overheating periods led to the conclusion that the analyzed building could function successfully without these additional installation elements. A proprietary tool for the analysis of microclimate conditions was proposed to estimate the hours of discomfort in a way that is objective and easy to calculate.

A Neural Network for Monitoring and Characterization of Buildings with Environmental Quality Management, Part 1: Verification under Steady State Conditions

Introducing integrated, automatic control to buildings operating with the environmental quality management (EQM) system, we found that existing energy models are not suitable for use in integrated control systems as they poorly represent the real time, interacting, and transient effects that occur under field conditions. We needed another high-precision estimator for energy efficiency and indoor environment and to this end we examined artificial neural networks (ANNs). This paper presents a road map for design and evaluation of ANN-based estimators of the given performance aspect in a complex interacting environment. It demonstrates that in creating a precise representation of a mathematical relationship one must evaluate the stability and fitness under randomly changing initial conditions. It also shows that ANN systems designed in this manner may have a high precision in characterizing the response of the building exposed to the variable outdoor climatic conditions. The absolute value of the relative errors ( M a x A R E ) being less than 1.4% for each stage of the ANN development proves that our objective of monitoring and EQM characterization can be reached.

Interior Insulation of Masonry Walls—Selected Problems in the Design

This article addresses the important problem of improving the energy efficiency of historic buildings, where due to the architectural value of the facade, thermal insulation should be placed from the inside. As a part of this publication, the author, on the basis of their own experience and research, presents and discusses selected problems to which special attention should be paid when designing this type of insulation. These are among other things: disturbances in the distribution of the temperature field on the partition; defects related to partial thermal insulation of partitions; the lack of detailed analysis of wall systems in terms of construction and their technical condition; wood decay; the selection of inadequate calculation methods, e.g., the simple method of Fokin–Glaser and many others. The author, on the basis of measurements and computational analysis, presents the methodology of a correct solution of such problems. This significantly simplifies currently applied methods.

Constructal Macroscale Thermodynamic Model of Spherical Urban Greenhouse Form with Double Thermal Envelope within Heat Currents

Urban agriculture is becoming a timely environmental friendly practice to strengthen cities’ resilience to climate change. However, there is a lack of academic literature regarding the thermodynamic potential of interior urban agriculture. Furthermore, there is always a need to develop, from scratch, an updated methodological approach that aims to assist architects of conceiving such specific thermodynamically complex interior environments. In this paper, urban space is identified as a ‘flow system’, and Bejan’s constructal law of generation of flow structure is used to morph and discover the system flow architecture that offers greater global performance (greater access to what flows). More precisely, a macroscale thermodynamic model of spherical urban greenhouse form with double thermal envelope has been developed while the methodological approach resulted in the definition of a decisional flowchart that can be reproduced by other researchers. On the basis of this macroscale constructal model, the present paper proposes reduced models that link thermodynamic and geometric parameters in an accurate manner and can be used at early design stages for pedagogic and qualitative optimization purposes, integrating urban farming to architectural programming.

A Novel Method Based on Neural Networks for Designing Internal Coverings in Buildings: Energy Saving and Thermal Comfort

Although several papers define energy saving and thermal comfort optimization with internal coverings materials, none of them deal with predictive models to improve design in building constructions. Thus, artificial intelligence (AI) procedures were applied in this paper. In particular, neural networks (NNs) were designed for indoor ambiences with internal covering materials in different buildings, were trained and employed to predict indoor ambiences (indoor temperature and relative humidity as a function of weather conditions), and, based on these procedures, local thermal comfort conditions and energy consumption, due to the type of internal covering permeability level, were calculated. Results from this original methodology showed a better acceptability of indoor ambiences when permeable coating materials were used, in agreement with previous research works. At the same time, with permeable coverings, a lower energy consumption of 20% in the heating, ventilation, and air conditioning (HVAC) systems was needed to reach more comfortable conditions during the summer season in the first hours of occupation. Finally, all these results suggest an original methodology to optimize indoor ambiences based on the design of internal coverings by NN.

Experimental Confirmation of the Reliability of Fanger’s Thermal Comfort Model—Case Study of a Near-Zero Energy Building (NZEB) Office Building

Designing and constructing near zero energy buildings (NZEBs) is a challenge not only from a structural point of view, but also from the point of view of ensuring appropriate climate comfort for users. The standards describing how to ensure comfort were created in times when the challenges of building ZEB/NZEB were not yet explored and energy issues were not as important as they are today. Therefore, the assessment of the thermal and climatic comfort of people living and working in such buildings requires a new or revised approach to the methodology of thermal comfort assessment. In this article, the authors present the results of a thermal comfort study based on measurements and thermal sensory tests. Testing was carried out in an experimental office building (passive standard). The main goal of the experiment was to compare the thermal comfort measurement method based on the ISO-Fanger model with the actual comfort results obtained by the panellists in the model office condition. The tests allowed the lowest operating temperature providing thermal comfort (predicted mean vote (PMV) = 0 and −0.5) to be determined. Sensory tests were conducted using three types of questions. The results were compared to the other researchers’ findings. It was noted that the panellists showed better thermal comfort sensation at lower temperatures than would result from the traditional Fanger distribution, so the authors proposed the experimental function of percentage of dissatisfied (PPD) = f(PMV). The authors hope that it contributed to the actual state of knowledge as a “small and specific scale” validation of the existing thermal comfort model. The results also revealed that the method of heating has an influence on the subjective thermal sensation.