Energy Sustainability, Resilience, and Climate Adaptability of Modular and Panelized Buildings with a Lightweight Envelope Integrating Active Thermal Protection: Part 2—Design and Implementation of an Experimental Prototype of a Building Module for Modular Buildings

Abstract

The integration of energy-active elements into the building envelope in the form of large-area heating/cooling, active thermal protection (ATP), thermal barriers (TB), and TABS represents a technical solution that is consistent with the principles of energy sustainability, resilience, and adaptability to climate change and ensures affordable and clean energy for all while protecting the climate in the context of the UN Sustainable Development Goals. The aim and innovation of our research is to develop energy multifunctional facades (EMFs) that are capable of performing a dual role, which includes the primary known energy functions of end elements and the additional innovative ability to serve as a source of heat/cooling/electricity. This new function of EMFs will facilitate heat dissipation from overheated facade surfaces, preheating of hot water, and electricity generation for the operation of building energy systems through integrated photovoltaic components. The theoretical assumptions and hypotheses presented in our previous research work must be verified by experimental measurements with predictions of the optimal operation of building energy systems. Most existing studies on thermal barriers are based on calculations. However, there are few empirical measurements that quantify the benefits of ATP in real operation and specify the conditions under which different types of ATP are feasible. In this article, we present the development, design, and implementation of an experimental prototype of a prefabricated building module with integrated energy-active elements. The aim is to fill the knowledge gaps by providing a comprehensive framework that includes the development, research, design, and implementation of combined energy systems for buildings. The design of energy systems will be developed in BIM. An important result of this research is the development of a technological process for the implementation of a contact insulation system with integrated ATP in modular and panel buildings with a lightweight envelope.

1. Introduction

The use of modern technical solutions for integrating energy-active elements into the building envelope, with functions such as large-area heating/high-temperature cooling, ATO, TB, and TABS, represents a technical solution that aligns with the principles of energy efficiency, resilience, and adaptability to climate change. This solution ensures access to affordable, reliable, sustainable, and modern energy for all while providing urgent measures to combat climate change and its consequences in the context of the United Nations’ Sustainable Development Goals.

Numerous scientific and technical publications have been published in this field of research, in which research teams from around the world describe their findings. We have described the results of our 20 years of research in several publications, for example, in [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. These documents offer optimal strategies for achieving a balance between energy consumption and thermal comfort in the built environment. Additionally, these publications emphasize the need for decarbonizing the building sector. An overview of important publications is provided in Section 2.1.

Energy multifunctional facades (EMFs), otherwise known as building structures with internal energy sources and active heat transfer control, are implemented using active thermal protection (ATP) pipe circuits. These circuits are positioned between the load-bearing structure of the building envelope and the external thermal insulation, as illustrated in Figure 1 [1,2,3,4,5,6,7]. Additionally, they may be situated within the concrete core between two thermal insulation layers, as depicted in Figure 2 [1,2,3,4,5,6,7]. ATP can alternatively be placed between the supporting structure of the building envelope and the external thermal insulation (internal ATP circuit) and at the same time under the external plaster (external ATP circuit), as shown in Figure 3 [1,2,3,4,5,6,7]. The pioneering work of Dr. Edmond Krecké in the field of ATP research is particularly noteworthy, as he was among the first scientists to utilize ATP, and his patented ISOMAX system is widely regarded as a significant contribution to the field [3,4,5].

The ISOMAX system was designed to utilize solar energy captured by energy roofs and stored in long-term ground heat storage for active thermal protection (ATP) in the energy function of a thermal barrier (TB). In summer, TB uses the coolness from the ground, where the temperature is approximately 5 to 12 °C all year round at a depth of about 2 m in our climate. Thus, an EMF with a TB can dynamically adjust the thermal resistance of the building envelope and, in conjunction with the building control system, can respond promptly to both sudden and long-term climate changes. The outer ATP circuit, located under the exterior plaster, utilizes geothermal energy to mitigate heat loss through conduction and cool the overheated surface of the facade in summer.

The aim and innovation of our planned research on the proposed experimental prototype module with a lightweight perimeter structure, which is currently under construction, is to develop variants of energy multifunctional facades (EMFs) capable of performing a dual role, which includes the following primary known energy functions of end elements: large-area radiant heating/cooling, active thermal protection (ATP), thermal barrier (TB), TABS, and an additional innovative ability to serve as a source of thermal/cooling/electrical energy (EE). This new function will facilitate heat dissipation from the overheated facade surface, preheating of hot water, and the production of EE for the operation of the building’s energy systems through integrated photovoltaic components.

Our research is inspired by the ISOMAX system, particularly in its utilization of renewable energy sources, waste heat, and active thermal protection (ATP), not only for thermal barrier (TB) applications. The underlying principle and prerequisite for the multifunctionality of building structures equipped with integrated ATP is illustrated in Figure 4 [1,2].

By analyzing and synthesizing existing research results, both from other scientists and from our research, we eliminate shortcomings by optimizing energy process strategies on experimental prototypes and combining the advantages of multiple heat/cooling sources and energy systems. The basic design of the energy multifunctional facades (EMFs) we have designed, and their energy functions, are shown in Figure 5. Our important innovations and differences are as follows:

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Use of ATP not only as TB but also in the energy functions of large-area low-temperature radiant heating/high-temperature cooling and TABS in combination with additional heat/cooling sources (e.g., heat pumps), Figure 5(2).

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Integration of energy-active elements (ATP) pipe circuits into thermal insulation panels, which are applied to buildings as a contact insulation system or even into entire modules of modular buildings (note: the ISOMAX system has been implemented in building structures using a classic wet system as large-area radiant wall heating), Figure 5(3).

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Using external ATPs not only to eliminate heat loss or cool overheated facade surfaces but also to preheat DHW, Figure 5(4).

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Integrating photovoltaic elements into the external structure of facade cladding, Figure 5(5).

The research will closely follow on from the VEGA 1/0118/23 project (Scientific Grant Agency of the Ministry of Education, Research, Development and Youth of the Slovak Republic and the Slovak Academy) ending in December 2025 entitled: “Alternative technical solutions for heat/cooling sources and energy systems in buildings using building structures with integrated energy-active elements using RES instead of fossil fuels in the context of energy security and self-sufficiency of buildings in the EU.”

The development and research on the designed and implemented experimental prototype module will focus on various technical solutions for thermal insulation panels with integrated energy-active elements, their material composition, alternative methods of connection to the distribution system, combination of EMF energy functions for all seasons, and combination of different heat/cooling sources in accordance with the principles of energy efficiency, resilience, and adaptability to climate change, and to provide solutions ensuring access to affordable, reliable, sustainable, and modern energy for all.

In this article, we present the development, design, and implementation of an experimental prototype of a prefabricated building module with integrated energy-active elements. The aim is to fill gaps in knowledge by providing a comprehensive framework covering the development, research, design, and implementation of combined building energy systems. The construction of the prototype module is currently underway. The design of energy systems is being developed in BIM. An important result of this research is the development of a technological process for the implementation of a contact insulation system with integrated ATP in modular and panel buildings with a lightweight envelope.

Our current research efforts focus on the analysis, theoretical and experimental verification, optimization, and development of technical solutions that can respond flexibly to climate change. The solutions must be energy-sustainable, durable, affordable, reliable, modern, and environmentally friendly. Potential solutions may include lightweight timber frame structures with integrated ATP elements for modular and panel buildings. The current implementation of modular and panel buildings with lightweight envelope structures is characterized as low-energy or passive. It is manufactured in a production hall in individual “modular” or “panel” units, as shown in Figure 6, Figure 7 and Figure 8.

The most important advantages of these buildings include [17]:

• Low heating and cooling costs (reduction of heat loss through the thickness of thermal insulation).
• Speed of construction (construction is several times faster than conventional masonry buildings, which require a myriad of wet processes to construct).
• Healthier and more comfortable living (forced ventilation using heat recovery air handling units, ideally with enthalpic heat exchangers = heat + moisture recovery).
• High-strength (modern panel and module structures have the strength of a monolithic shell), larger usable area (these buildings provide 7%–10% more usable area than conventional masonry buildings).
• Stable insulation (the insulation core of modern modular and prefabricated buildings is strong and stable even after decades; it cannot get wet, sag, or misapplied as can happen with conventional prefabricated frame structures, which are technologically demanding).
• A certified system with guarantees (the production process is subject to regular inspection by a notified person, and each component must be certified).
• Environmental aspects and sustainability (modular and prefabricated buildings classified as timber buildings allow for the overall production process, the construction of the building, as well as the possibility of recycling the materials, thus significantly reducing CO₂ production).

The modules are brought to a designated location after the manufacturing process is completed, where they are placed on a preprepared substrate. Once the module is installed and connected to the utility network, the customer can start using it almost immediately, as shown in Figure 7. The modules can be connected and expanded according to the customer’s needs. If necessary, the modules are designed to be movable to another location in the future [17].

By panel construction, we mean construction based on individual stand-alone panels that are premanufactured and premarked, Figure 8. The panels are assembled according to an assembly project, which forms part of each construction delivery. The method of individual panel construction ensures the possibility of construction in any conditions. The panels are lightweight (approximately 22 kg/m²), and therefore, no heavy construction machinery is required for handling. Two on-site workers can easily handle the panel. For the customer, this, therefore, allows construction even in hard-to-reach places where it is not possible to access construction mechanics. The use of panels is ideal for dealing with superstructures and extensions where the original building would not have been structurally capable of coping with traditional construction systems, such as masonry or concrete. They can also be used for buildings on water, such as houseboats. Installation of individual panels is very simple, fast, and precise. In most cases, three to four trained installers are sufficient to assemble the panels [17].

The potential of modular and prefabricated buildings with a lightweight envelope that includes active thermal protection is also justified from a humanitarian perspective, as they meet the requirements for rapid construction in areas devastated by natural disasters or military conflicts. In such contexts, passive cooling techniques are the preferred strategies for improving the indoor thermal environment. Significant challenges in the field of lightweight, modular, integrated structures include determining the optimal parameters of exterior walls to minimize energy consumption throughout the life cycle, as well as economic costs and environmental impact. The ATP system shows considerable potential for energy savings and application in the construction of energy-sustainable, resilient, and climate-adaptive buildings, particularly given its compatibility with renewable energy sources, low-temperature heating systems, and high-temperature cooling systems, thus meeting the UN SDGs, in particular, Sustainable Development Goal 7 “Affordable and Clean Energy” and Goal 13 “Climate Action.”

2. Materials and Methods

The design and implementation of the experimental prototype module with a prefabricated lightweight building envelope with integrated active thermal protection is based on a review of scientific and technical articles presented in Section 2.1. Section 2.2 describes the development and design of the experimental prototype module. Finally, in Section 2.3, we describe the planned use of BIM in the design, future operation, and maintenance of the research facility.

2.1. Overview of Scientific and Professional Studies

Given the complexity of our research focus, which includes the construction of two experimental houses over the past 20 years, the establishment of a mobile laboratory focused on research into intelligent compact devices (ICDs), the creation of prototypes of thermal insulation panels with integrated ATP, and the performance of several parametric studies and computer simulations, as part of the development and research of energy multifunctional facades (EMFs) [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. This section contains an overview of scientific and technical articles focused on modular and panel buildings with lightweight envelope structures. We also present an overview of scientific articles describing the application of BIM (Building Information Modeling) and BEM (Building Energy Modeling). The reason for this is that the prototype of the experimental module, energy systems, and heat/cooling sources will be designed using a building information model. The aim is to create and manage building data throughout its life cycle as a tool for efficient construction and management of buildings. A comparison and justification of the selected EMF design are provided in the introduction, with the approach to be taken grounded in the findings of earlier studies and research results.

Chang, S.J., Kang, Y., Yun, B.Y., Yang, S., and Kim, S. [18] argued that cross-laminated timber (CLT’s) advantages over timber include better accumulation of carbon and insulation. Its modular construction offers a significant reduction in construction time and cost, as well as high productivity. Their study assessed the hygrothermal performance of cross-laminated timber (CLT) walls in the context of modular construction for future climates. Firstly, CLT walls with plywood in a core layer were manufactured. Then, a CLT building mock-up was produced, and its construction was analyzed. The hygrothermal behavior of the CLT walls was simulated using WUFI, and the results were verified against measurements from the experiment. The hygrothermal performance was finally evaluated for four insulators and future US climates. The coefficient of variation coefficient of variation—root mean square error (CV(RMSE)) of the temperature inside the ply-lam CLT wall from experiments and simulation evaluations was 6.43%, meeting validation criteria. Based on hygrothermal performance, the extruded polystyrene insulation was evaluated as safe from moisture problems in all eight cities. However, the risk of mold growth increased in all regions and insulator types under climate change and higher temperatures.

Volpe, S., Sangiorgio, V., Petrella, A., Coppola, A., Notarnicola, M., and Fiorito, F. [19] stated that the fourth industrial revolution is transforming the construction industry. In the last decade, shapes, materials, and methods have evolved rapidly due to additive manufacturing technology. However, the potential of concrete 3D printing in building prefabrication has yet to be fully explored. The paper proposed a new design and prototype of a precast building envelope to be prefabricated with extrusion-based 3D concrete printing (3DCP), aiming to fully exploit the potential of 3D printing for prefabricated components. Beyond the design, research tested a 3D printable cementitious material based on a magnesium potassium phosphate cement (MKPC). The prototype was realized in scale using additive manufacturing technology to verify printability and optimize the extruder path. This demonstrates how the use of prefabricated systems, construction automation, and innovative materials can enhance the sustainability of the construction industry.

Maracchini and D’Orazio [20] stated that lightweight structural systems are often employed to rapidly construct emergency architectures following catastrophic events. However, suppose that environmental control systems are not in place (as is often the case). In such cases, these buildings can lead to poor indoor thermal conditions, especially in hot climates, which can be detrimental to occupants’ health. Passive cooling techniques are preferred to improve these conditions. However, very few studies have evaluated the effectiveness of such measures on emergency buildings, and few consider different climates, costs, and feasibility. In their study, the thermal performance of a 3D-reinforced EPS panel system was examined, which had not been adequately studied to date. A numerical model for experimental data was calibrated, then, using a reference building (recently adopted in emergency scenarios), the authors evaluated and improved the thermal performance of the building in hot and temperate climates through passive cooling measures (e.g., shading, thermal buffering, ventilation, and cooling materials). The results show high summer thermal discomfort in all climates. The measures are effective depending on the climate. For example, combining natural ventilation with cool roof materials or blinds (for temperate and hot climates) provides the best balance between thermal comfort, costs, and feasibility. However, the complete elimination of summer indoor thermal discomfort remains elusive. The study helps decision-makers and individuals improve living conditions and the sustainability of emergency architecture.

The primary objective of the study by Blanchet, P., Perez, C., and Cabral, M.R. [21] was to examine recent developments in the utilization of wood-based building materials and systems over the past 5 years. The methodology was carried out by using the systematic review procedure. This study considered only peer-reviewed articles written in English and published over the last 5 years (2018 to 2022) on materials used in structural systems and building envelopes. The energy demand for cooling and heating accounts for 40% to 60% of a building’s total energy consumption, depending on the energy mix. Every increase in energy efficiency increases the pressure on the energy embedded in the materials. In this context, bio-based and, in particular, wood-based materials are gaining popularity. Their use is significant in structural and envelope systems, making them a powerful tool for working on both efficiency and embedded energy. The building construction industry is among the most significant in the economy of industrialized countries.

Sarmento et al. [22] stated that in emergencies, access to temporary housing for displaced people must be ensured rapidly. This is essential for effective disaster response. Managing this issue promptly addresses the immediate needs of the population and fosters a sense of stability. However, given the size of emergency camps, there is often a high number of shelters to install. This needs rapid transport and assembly for the settlement procedures to be successful. Furthermore, emergencies often occur during extreme weather, making it difficult to maintain comfort in shelters. The present study examines a modular shelter constructed from composite sandwich panels composed of glass fiber–reinforced polymer (GFRP) filled with a polyurethane (PUR) foam thermal insulation core. Experimental tests and numerical analyses are used to quantify the thermal conductivity of the panels and the heat losses through the connections between the panels. Dynamic energy simulations are implemented, taking into account the aforementioned data. These are used to quantify the energy needed to ensure users’ thermal comfort via active heating and cooling systems. The model is also applied to evaluate the influence of finishes and shading devices on reducing the shelter’s energy demands in three extreme climates. The results show that a combination of shading and reflective finishes can reduce energy demands, decreasing the need for thermal insulation and reducing the overall weight of the shelter. Ultimately, passive cooling strategies can achieve energy savings that exceed those attainable with thermal insulation alone, particularly in climates where cooling demands are predominant.

Jia et al. [23] proposed an innovative prefabricated modular building that is energy-efficient and sustainable. To ensure energy efficiency, the paper investigated the thermal performance of the building’s outer enclosure walls by testing T-joint and tie bar specimens. The tests indicate that GFRP tie bars exhibit superior thermal performance. FE models are established to assess insulation materials and thickness, and a thermal analysis method for the envelope structure is proposed. The optimal thickness of various insulation materials is calculated based on the average and structural thermal bridge heat transfer coefficients. For cold regions, the recommended thicknesses range from 200–260 mm for graphite polystyrene board, 200–280 mm for rock wool board, and 210–320 mm for foam glass board.

Hu, Y., Ai, Z., Zhang, G., Zong, J., and Liu, Z. [24] discussed the challenge of determining the optimal exterior wall parameters for modular integrated constructions (MICs) to minimize life-cycle energy consumption, economic cost, and environmental impact. The study compared 3E and single-objective optimization methods for the thickness of MIC in China. Factors such as heating, ventilation, and air conditioning (HVAC) operational duration, climate change, grid emission factors, and building lifespan all affect the optimal thickness. The 3E optimization method achieved the highest cost–benefit ratio in carbon reduction. Lightweight external walls have an optimal thickness, deviating from the current nearly zero-energy building standard by up to 200 mm. Reductions in HVAC operational duration, global warming, grid emission factors, and extended building lifespan could potentially decrease the optimal wall thickness by up to 140 mm; however, this could also be detrimental. Deviations in HVAC operational duration have the most significant impact on life-cycle 3E results, reaching up to 8.4%. Climate change has a minimal impact. This research could improve the cost–benefit ratio for MIC carbon emission reduction and emphasize the need for flexible building standards.

As Zhang, Chen, Gasparri, and Lucchi [25] stated, many challenges face cities. Climate change, urbanization, and food security have made people focus on sustainable vertical farming and renewable energy solutions. Building facades, often underutilized in high-density urban environments, present an opportunity for multifunctional buildings incorporating photovoltaic (PV) systems and vertical farming modules. On vertical surfaces, these two systems often compete for space. Their research focused on a multifunctional agrivoltaics building envelope (ABE) system utilizing building-integrated photovoltaics (BIPV) technology and vertical hydroponic farming. The ABE system is a modular design, with each unit prefabricated and bolted together for easy construction. The design process includes 2D cross-sectional technical design, assembly sequences, and an analysis of key design parameters through 3D modeling. Their research used a Research through Design (RtD) and Research for Design (RfD) approach to bridge prototyping, testing, and performance optimization. The paper highlighted the potential of integrating renewable energy with agricultural production in building envelope systems. By addressing space optimization and multifunctionality, their research provides a practical framework for future applications in urban sustainability.

Parracho et al. [26] claimed that modular construction is superior to traditional building methods when combined with digital technologies. This literature review assesses recent advances in digital modular construction for a sustainable and climate-neutral built environment, identifying research gaps and trends using the PRISMA method. The review integrates digital technologies with modular construction, extending the analysis to efforts to use circular and bioclimatic designs, renewable energy sources, and passive building design strategies. While most literature focuses on BIM, IoT applications leveraging real-time data for sustainability are also discussed. Building Energy Modeling (BEM) and Life Cycle Assessment (LCA) tools are frequently discussed in the context of climate-friendly housing. Despite the push for sustainable modular construction strategies, machine learning, and artificial intelligence applications are underexplored. Only a few papers mention reaching nZEB requirements despite the focus on passive building solutions and renewable energy sources. Material circularity is not yet at its full potential. There is some interest in off-grid modular buildings, although further research is needed to analyze the feasibility of their modular construction for sustainable off-grid communities. Ultimately, the review concludes that digitalization can enhance efficiency and promote environmental sustainability in the architecture, engineering, and construction (AEC) sector.

Gong Q et al. [27] focused on enhancing the energy performance and environmental characteristics of public rental housing (PRH) in cold regions of China. PRH plays a crucial role in providing basic housing security in major Chinese cities. The authors proposed low-energy consumption strategies for buildings. Three-dimensional parametric modeling of PRH modules was performed using Grasshopper and Rhino software (version No. 6), and building performance simulation was performed using plug-ins such as Ladybug and Honeybee. The Energy Use Intensity (EUI) was reduced by improving the building envelope, and the Thermal Discomfort Percentage (TDP) and Useful Daylight Illuminance (UDI) were increased. Sensitivity analysis was performed using the SRC and TGP methods, and the Octopus plug-in was utilized for multiobjective optimization that considers daylighting, thermal comfort, and energy consumption. The findings show that the optimized equilibrium model reduced the EUI by approximately 20.9%, the TDP by about 47.0%, and the UDI by approximately 13.8%. This integrated approach effectively optimizes PRH performance and provides a robust framework for future applications in similar climate conditions.

A plethora of other significant scientific papers have been published in the field of modular and panelized construction. The present review is not intended to provide a comprehensive overview of all relevant publications; rather, it is an attempt to draw attention to other scientific works that may be of interest to the reader [28,29,30,31,32,33].

Pan, Y., Zhu, M., Lv, Y., Yang, Y., Liang, Y., Yin, R., Yang, Y., Jia, X., Wang, X., Zeng, F., and Huang, S. [34] stated that building performance simulation (BPS) is important in the building industry because of the support of building energy modeling (BEM). Researchers and tool developers face both opportunities and challenges when applying BEM at various levels and stages of building energy management. Their paper reviewed recent studies and demonstrated how BEM can be utilized to manage energy in various ways. The paper also discussed the research’s objectives, the tools that can be employed, and their application. It examined the latest research and identified potential future directions, offering suggestions. It also discussed the integration of BPS with other systems.

Alhammad, M., Eames, M., and Vinai, R. [35] argued that, due to population and energy demand, energy efficiency in buildings is becoming increasingly essential. Architectural firms are moving from traditional Computer-Aided Design (CAD) to Building Information Modeling (BIM). However, buildings consume nearly 40% of the world’s energy. Therefore, there is a need to integrate Building Information Modeling (BIM) and Building Energy Modeling (BEM), demonstrating how BIM can minimize energy consumption by combining building information software with data from existing energy-efficient building automation systems (EBAS). BEM is a form of computational analysis that can be utilized in conjunction with BIM or CAE systems. The paper explored the literature on BIM and BEM and the effect of BEM in the design phase of projects. A recent survey was conducted on the Google Scholar, Web of Science, ScienceDirect, and Scopus databases. Papers were screened, and it was found that BIM and BEM are useful in practical applications, although short life-cycle projects might not be suitable. Challenges exist with interoperability tools, with data exchange restricted. Binary translation is the best data exchange option. Analysis showed that the most used program for integrating BIM/BEM is Green Building Studio, developed by Autodesk to improve construction and operational efficiencies.

Guo, H., Chen, Z., Chen, X., Yang, J., Song, C., and Chen, Y. [36] stated that many existing and aging buildings urgently need retrofitting and renovation but lack accurate information on their geometry and energy consumption. The study introduced an automated platform for building information modeling (BIM) to generate building energy modeling (BEM). This platform enabled the creation of energy models to estimate energy consumption and perform retrofit analysis. A four-story office building in Hong Kong was selected for the case study. The building images were transformed into a 3D point cloud model. The point cloud model was provided to Revit to generate the BIM model in Industry Foundation Classes (IFC) format. This IFC file, containing the geometric information of the building, was supplied to the AutoBPS-BIM tool to generate the BEM model in EnergyPlus for simulating energy consumption. The annual electricity use intensity (EUI) of the building is 145.05 kWh/m². The energy model was used to evaluate the energy-saving potential of cooling, lighting, and window replacement. The electrical energy savings are 17.22%, 6.91%, and 6.61%, respectively. This research demonstrates that the UAV-BIM-BEM (Unmanned Aerial Vehicles-Building Information Modeling-Building Energy Modeling) platform has potential for BEM modeling in existing buildings and building energy retrofitting.

In addition to the scientific papers described in more detail, which deal with computer simulations and modeling of energy phenomena in buildings, further studies closely related to these promising research methods are recommended, particularly in the construction and building energy systems [37,38,39,40,41,42,43,44,45,46,47,48,49].

2.2. Development and Design of an Experimental Prototype of a Prefabricated Modul

The development and research of lightweight envelopes for modular and panelized buildings with an integrated thermal barrier is closely related to the verification of theoretically obtained results and assumptions from parametric studies and computer simulations on a real building exposed to external conditions and climatic changes, which are increasingly extreme in our temperate climate zone, especially in the summer period. For the aforementioned reasons, an experimental prototype of a prefabricated module is being developed in two alternative compositions of the lightweight building envelope with ATP for experimental measurements of different energy functions. The first investigated lightweight building envelope with an integrated ATP will be one with a thermal barrier energy function. The investigated quantities will be the dynamic thermal resistance R_DYN ((m²·K)/W), dynamic heat transfer coefficient U_DYN (W/(m²·K)), and the dynamic thermal insulation thickness d_DYN (m), as illustrated in Figure 9a,c [50]. The second investigated lightweight building envelope with integrated ATP will feature an energy function that serves as a thermal barrier, cooling the superheated facade surface and preheating domestic hot water through the ATP placed on the exterior wall of the façade, as shown in Figure 9b,d.

The prototype module, featuring a lightweight building envelope with integrated ATP, has been designed with the following specifications: a length of l = 4180 mm, a width of w = 2930 mm, and a height of h = 3688 mm. The module is composed of an anteroom and a main room dedicated to experimental measurements of indoor environmental parameters, as shown in Figure 10. The figure shows the floor plan, transverse, and longitudinal sections of the research object.

2.3. The Use of Building Information Modeling (BIM)

Digital technologies, such as Building Information Modeling (BIM) and the Common Data Environment (CDE), are imperative tools in the modernization of the construction sector. The implementation of integrated active thermal protection measures, such as active facades or intelligently controlled heating and cooling systems integrated directly into building structures, necessitates precise coordination among designers, manufacturers, and installation teams. In this context, the BIM environment provides an ideal platform for integrating data from all phases of the building life cycle, from design through production to operation.

The BIM environment facilitates the design of individual active thermal protection panels, with each element capable of being enriched with technical and material information. This information can then be managed in a CDE, thereby providing a unified and controlled environment for the sharing of data across professions. Such an approach has the potential to mitigate the risk of project non-conformances and optimize the quality feedback control process, thereby aligning with ISO 9001 [51] requirements.

The integration of artificial intelligence (AI) within the design process represents a significant innovation and a potential solution. Specifically, AI algorithms can analyze a range of input data, including climatic conditions, building orientation, and energy requirements. Through this analysis, AI algorithms can then design the optimal placement, sizes, and types of active protection panels. When employed in conjunction with generative design within a BIM environment, this approach facilitates the automated generation of multiple solution options, thereby optimizing parameters such as heat gains, energy consumption, and production efficiency. Concurrently, AI could be instrumental in predictive control of production processes and the enforcement of ISO 9001 quality standards, thereby enhancing the precision of automated outputs. The integration and interconnection of these individual elements would facilitate the development of an efficient, fully automated solution that significantly enhances quality, reduces lead times, and mitigates the risk of errors.

Building Information Modeling (BIM) will be utilized in the design of an energy system for a prototype module featuring a lightweight perimeter structure and integrated ATP. In the initial phase, a 3D model was created (see Figure 11). The use of clash detection tools facilitates the identification and elimination of conflicts between the piping routes of various systems and building elements. This approach is expected to eliminate the need for additional costs during implementation and reduce the time required for construction. The integrated functions of the BIM software will facilitate the optimization of pipe diameters and pump outputs, as the subsequent model of the energy systems will encompass all pertinent input data, including pipe lengths, fittings, and elevation levels [52,53,54,55,56].

The BIM application facilitates the dissemination of information regarding alterations to the digital model to all relevant parties, including responsible engineers and contractors. This ensures that all stakeholders are informed of the latest modifications and can provide feedback or contribute to the model’s development. Revisions made to the drawings will be automatically reflected in the deliverables, thereby minimizing the risk of outdated documentation. Furthermore, the finished model can be utilized to automatically generate a variety of reports, including pipe lengths, the number of valves and fittings, and material calculations for a contact insulation system with integrated energy-active elements. These reports can then be used, for example, as a basis for procurement. Following the completion of the experimental prototype of the module, the BIM model will persist as a digital twin of the research object. In the event of any subsequent modifications or extensions, the research team will be able to swiftly determine the precise parameters of the piping and equipment (e.g., types of elements used, pipe diameters, element positions, etc.) [52,53,54,55,56].

3. Results

3.1. Results of the Development and Design of an Experimental Prototype of a Modul with ATP

Following the theoretical analysis and optimization of the lightweight envelope of modular and panelized buildings in the function of a thermal barrier (TB), experimental measurements are planned to verify the results and assumptions. An experimental prototype of a model with ATP is currently under construction.

3.1.1. Location Description

The location of the research object is in the city of Nitra, Slovakia (Figure 12). From the point of view of the energy balance of the buildings, the following data are characteristic of the site: outdoor design temperature θ_e (°C), average annual outdoor temperature θ_e,m (°C), average outdoor temperature in the heating period θ_e,average (°C), and the number of days of the heating period n (-) in the sense of the standards STN EN 12831-1 [57] and STN 38 3350 [58]. For comparison, we present these values for several cities in Slovakia, organized by location (

Table 1. Outdoor design temperature θ_e (°C), average annual outdoor temperature θ_e,m (°C), average outdoor temperature in the heating period θ_e,average (°C), and number of days of the heating period n (-) [57,58].

Geographical Zone (City)	Height Above Sea Level (m)	Outdoor Design Temperature θe (°C)	Average Annual Outdoor Temperature θe,m (°C)	Average Outdoor Temperature in the Heating Period θe,average (°C)	The Number of Days of the Heating Period n (-)
Bratislava	142	−11	9.9	4.3	208
Košice	205	−13	8.4	3.3	226
Nitra	190	−11	9.6	4.1	212
Prešov	257	−15	8.3	3.1	226
Trnava	146	−11	9.5	4.0	214
Žilina	344	−15	7.2	3.3	246

).

3.1.2. Technological Prescription for the Implementation of ATP on a Prototype Building

A key finding of our research endeavor is the formulation of a technological prescription for implementing active thermal protection on a prototype building module with a lightweight envelope.

Purpose of the Technological Regulation

The subject of technological regulation is the method of mounting premanufactured panels with integrated active thermal protection (ATP) on a module prototype of a lightweight building.

Scope of Validity

The present code of practice is intended for all persons involved in the transport, assembly, installation, or fitting of panels with integrated active thermal protection (ATP) on a prototype modular cell intended for research purposes.

General Information

The prototype module with the lightweight envelope has overall dimensions of 4180 mm in length, 2930 mm in width, and 3688 mm in height. The configuration of the module comprises an anteroom and a primary chamber intended for the execution of experimental assessments of indoor environmental parameters. The clear height of the structure is 2500 mm. The prototype module is mounted on a paved surface and mechanically anchored to concrete blocks. The roof is flat, with a foil covering and extensive greenery (a substrate with Sedum acre planting). The roof attic is elevated above the plane of the roof. The thickness of the outer skin is 300 mm, and the thickness of the roof skin, including the green roof, is 445 mm.

In Figure 10 of Section 2.2, we present the plan and sections of a prototype building module featuring a lightweight envelope, which will be used for active thermal protection (ATP) performance research.

Basic thermal insulation panels with integrated active thermal protection consist of polystyrene insulation boards with a minimum thickness of 100 mm and built-in pipe distribution into the system profiled plastic board. Additional thermal insulation panels, in standard dimensions of 1000 × 500 mm and a minimum thickness of 100 mm, form the duct cover during the installation of the supply and return ducts and the connection to the heating circuits.

Each base panel in the longitudinal direction (longer wall) of the modular cell has an overlap of 100 mm across the corner of the envelope, which serves to close the contact with the base panel in the transverse direction of the module envelope. Each base panel shall have a minimum 80 mm free edge on the interior side of the perimeter (excluding the surface with the profiled plastic sheet) for the application of adhesive mortar.

The size of the base panels is predesigned according to a cladding plan that respects the possibility of connection to the heating/cooling system and also the position of the hole fillers on the facade of the prototype.

Figure 13 illustrates the cladding plan for the base panels of the active thermal protection (ATP) system on a prototype building module featuring a lightweight envelope, as well as the position of the installation duct. The cladding plan is designed separately for each exterior wall (wall W1–W4) of the prototype module.

Construction Preparation

a.

Readiness of the building, object, and structure

For the installation of the active thermal protection system, it is necessary to prepare the structure on which the individual mounting panels will be mounted. At the same time, penetrations must be made through the envelope of the prototype building module for all piping to connect the tubular heating/cooling system to the heat/cooling source (HCS) located in the interior of the module. The location of the penetrations is evident from the location of the water pipes in the PD-cladding plan. The surface of the envelope must be dry without water film (after rain), sufficiently flat (differences greater than 5 mm must be repaired), and free of dust and possible dirt for the application of the primer.

b.

Workplace readiness

The site requires a water supply for the preparation of the adhesive mortar and an electricity supply for the use of small machinery in the assembly of the premanufactured panels.

c.

Preparation of the construction site

The construction site requires, in particular, a drained area for storing basic and additional panels of the active thermal protection system, their assembly components, and a water and electricity supply. Additionally, it requires an access road and fencing of the construction site to prevent unauthorized persons from entering. The interior of the prototype building module can be used for storing materials, subject to weather conditions; it is not necessary to provide a separate enclosed warehouse.

Materials Used

For the implementation and installation of the contact structure (insulation panels) for active thermal protection, a soak-in primer and an adhesive mortar designed for application on a wood-based substrate will be used, including reinforcing mesh and corner beams. A system foundation strip, comprising a system aluminum profile to enclose the ATP contact system above the plinth, or a timber foundation strip, will be used to fit the ATP base panels at the plinth level of the prototype building module. The base panel contact structure itself is a semi-finished product manufactured off-site. It will be transported to the site by normal means of transport with no particular demands on the dimensions or load capacity of the vehicle. Transportation will be provided in a comprehensive range in one cycle (one at a time). Prepared areas around the module and the interior of the prototype building module will be used for storage of materials. Figure 14 lists the element-base ATP panels for each wall of the prototype building module, including their sizing characteristics.

Technological Procedure of Works

a.

Preparatory work

The preparatory work includes the installation of an auxiliary structure-trestle or sliding scaffolding, which will allow the safe and high-quality installation of the panels at a height of 1.5 m above the ground.

b.

Semi-finished products (production, transport)

No additional semi-finished products will be manufactured on site for the fitting and assembly of the ATP panels for the individual walls of the prototype building module.

The adhesive mortar for the application of the panels to the substrate—the wall of the wood-based the prototype building module—will be produced. The adhesive mortar will be mixed according to the manufacturer’s instructions, on site using an electric mixer in an impermeable container—a bucket. The addition of any antifreeze additives to the adhesive mortar is not permitted. The addition of any quantity of water to dilute the adhesive mortar during the bonding process is not permitted.

A cover insulation panel without ATP will be manufactured separately to enclose the installation channel and homogenize the envelope construction. The covering insulation panel is manufactured as atypical, separately for each wall of the prototype building module by cutting out the necessary shape from mineral wool (MW) based insulation boards.

c.

Composition of work teams, equipment of work teams with tools and machinery

For the implementation and installation of the active thermal protection system, it is necessary to deploy two separate crews consisting of at least two masons and two plumbers. The team shall include a person qualified to carry out construction management and quality control. For the teams (individual work crews), basic small machinery with a connection to electricity or accumulators (drill, stirrer, screwdrivers, hammers, pliers, tighteners, etc.) is required. For the application of priming and adhesive mortar, it is necessary to equip the workers with a brush, roller, containers, and a trowel. For checking the quality of the substrate flatness, installation of the foundation strips, and installation of the ATP panels, a spirit level, plumb bob, and laser device are needed.

d.

Progress of work

• Wall W1 and W3

• Cleaning of the substrate/exterior surface of the perimeter wall No. W1 of the prototype building module from any dust and dirt from the construction. Cleaning is to be carried out by plastering or vacuuming with an industrial vacuum cleaner.
• Levelling of the substrate as required and removal of protruding wooden elements of OSB boards, sawdust, and cuttings.
• Implementation of the adhesion bridge and priming of the substrate in two perpendicular layers with a primer designed for absorbent substrates (wood/wood–composite materials). Apply the coating with a roller, observing the specified consumption per m².
• Technological break according to the primer manufacturer’s specifications.
• Drilling holes for the foundation strip into the load-bearing part of the cladding structure. Fitting the foundation strip to the level of the position of the lower edge of the base panel No. W1/8, S1/7, and W1/6 in the plane.
• Application of adhesive mortar with a trowel along the entire length of the free edge of the insulating part of the base panel, including a minimum of three separate mortar targets in the area. Apply the targets outside the pipework.
• Fit and glue the base panels into the space of the system aluminum base batten, or in the case of a timber batten, to the top level of such base batten.
• Take a technological break as necessary to allow the adhesive mortar to cure and to eliminate buckling/buckling when transferring the vertical load of the W1 panels located above.
• At the time of the technological pause, drill holes for the dowel bar into the load-bearing part of the envelope structure at wall W3.
• Set the dowel bar to the level of the position of the bottom edge of the base panel No. W3/4 and W3/3 using a spirit level in the plane.
• Then apply the adhesive mortar to the W3/4 and W3/3 base panels in the same way and fit to the face of the perimeter wall.
• The other panels above the level of the first row of walls W1 and W3 shall be fixed to the perimeter structure in the same way, using adhesive mortar applied around the entire edge of the free part of the insulation board and in a minimum of three separate targets in the panel area.
• The bonding of the remaining rows of panels is accomplished by alternating the W1 and W3 walls.
• The edges of the panels on walls W1 and W2 must be fitted on the corners with an overlap in the thickness of the insulation board (min. 100 mm).

• Wall W2 and W4

• The W2 and W4 wall is implemented in the same way.
• The edges of the panels on walls W3 and W4 are soldered to the level of the corner of the envelope of the prototype building module.
• After the base panels are installed, the anchoring of the supply and return ducts is carried out directly on the perimeter cladding of the prototype building module in the area of the omitted installation duct.
• This is followed by the connection of the ATP base panels to the supply and return piping, as well as the connection to the piping in the envelope of the prototype building module.
• After a positive inspection of the pipe connections, the sealing of the installation duct is carried out with an atypical-shaped mineral wool insulation element, which is manufactured from standard dimensions on site.
• Once the ducts have been sealed on all walls of the prototype modular cell, a reinforcement/protection layer will be implemented at the corners of the fitted ATP panels and the locations of the MW cover panels.
• The reinforcement layer is implemented in three steps: application of the adhesive mortar, placement of the reinforcing mesh, and closure with the reinforcing mortar by a wet-in-wet system.
• At corners, the overlaps of the reinforcing mesh over the edge of the corner must be kept to a minimum of 100 mm. The corners can also be reinforced with a system element, such as a corner beam.
• Mesh overlaps of min. 80 mm must also be maintained at the point of change of the insulation material, the overlapping junction of the installation duct, and the ATP base panels.
• Finally, a sealing profile is fitted in the joint of the attic flashing and the highest panel around the entire perimeter of the prototype building module.

Figure 15 shows a detail of the corner with the connection of the ATP base panels in the longitudinal and transverse directions of the envelope of the prototype building module and a detail of the connection of the base panels to the duct cover panel.

e.

Organization of work in space and time

This part of the technological prescription can be completed after the prototype of the module has been realized.

f.

Process labor intensity, unit cost, duration

This part of the technological prescription can be completed after the prototype of the module has been realized.

g.

Treatment and protection of the product

Product protection is required during ATP implementation. Wet processes (adhesive bridge, panel bonding, reinforcement layer) can be carried out in the temperature range of +5 °C to +30 °C. The substrate and the wet processes in the ATP construction must be protected from direct precipitation and sunlight during implementation. This protection should be implemented in the event of the need to interrupt the work or after completing a sub-process by overlapping or creating a separate barrier on the scaffolding. The finished product, featuring a mature and dry reinforcement layer, does not require special protection, as it is designed for outdoor use.

h.

Finishing work (e.g., dismantling of ancillary structures) and readiness for downstream processes

After mounting the panels W4/1 to W4/4 on wall 4, covering the joints of the corners and the joints of the base panels with the installation panel with a reinforcing layer, and closing the contact of the panels under the attic sheathing, the auxiliary scaffolding structure will be removed. Monitoring the effectiveness of the active thermal protection of the prototype module will be part of the energy system equipped with the building management system.

i.

Inspection and test plan

• Initial check:

• Delivery of materials, panels, and related components (number, size, damage) and compliance with PD.
• Substrate cleanliness, moisture, and flatness.
• Location of penetrations for system connection.
• Climatic conditions for application of primer and adhesive mortar.

• Interoperative control:

• Position and flatness of the installation of the foundation bar.
• Number of coats and primer consumption.
• Consistency of adhesive mortar.
• Method and extent of application of adhesive mortar.
• Position of the base panels in accordance with the cladding plan.
• Width of overlap of the base panels at the corners of the prototype module.
• Position and anchoring of the piping for the system connection.
• Interconnection of the pipe panel system with the supply and return pipe in the ducts and connection to the interior penetrations.

• Output inspection and inspection of finished work:

• Functionality of the ATP pipe system.
• Overlaps of the reinforcement grid across the corner joints and the joints of the supplementary panels (on the installation channels) with the base panel.
• Sealing of the base panel and attic flashings.

Health and Safety at Work

The technological regulation will also encompass an analysis of potential safety risks and the proposal of appropriate measures for their mitigation.

Environmental Protection

The Technological Regulation also encompasses the following aspects. Firstly, it identifies the harmful effects on the various components of the environment. Secondly, it puts forward measures to eliminate these harmful effects. Thirdly, it identifies the categories of construction waste, as well as the quantification of their respective quantities.

3.2. Construction Progress

The construction of the prototype module, featuring a lightweight building envelope and integrated ATP, is currently in the post-construction phase, following the completion of rough construction, as illustrated in Figure 16. Following this, the production of thermal insulation panels with integrated ATP will commence in the layer between the load-bearing part and the thermal insulation part, as well as in the layer below the external facade treatment. Finally, the manufactured panels are applied to the walls of the test module in a manner analogous to that of the contact thermal insulation system.

4. Discussion

A limitation of the parametric study and computer simulation results presented in Part 1 is the lack of experimental analysis under realistic conditions, which may affect the transferability of these results. The model assumes a constant temperature of the heat transfer fluid, which may not accurately reflect actual operating conditions. Therefore, further research will focus on the experimental verification of these results in a real environment, specifically examining the effect of temperature and weather fluctuations on the performance and energy efficiency of ATP embedded in lightweight envelopes of modular and panelized buildings. The practical application of these findings may be important in strategies to optimize the operation of combined building–energy systems in buildings, especially in combination with renewable energy sources, waste heat, and low-temperature heating and high-temperature cooling. For these reasons, we have developed and designed a prototype test module for a building with a lightweight envelope, which is currently under construction.

In the future, we will pay closer attention to various thermal insulation materials and their combinations with ATP, as well as to the investigation of heat transfer dynamics under different climatic conditions. We also plan to combine research on the use of ATP under the external surface of the facade in combination with integrated photovoltaic energy elements. We hypothesize that cold water extracting heat from the overheated façade, used for preheating the DHW, can increase the efficiency of the PV as it is known that the efficiency is higher at lower temperatures. These investigations can contribute to the better design of energy-efficient building systems.

The research and development of modular and panelized buildings with lightweight building envelopes that incorporate active thermal protection is also justified from a humanitarian perspective, as it meets the prerequisites for rapid construction in devastated areas following natural catastrophic events or even military conflicts. As Maracchini and D’Orazio [20] observed, lightweight structural systems are often employed in the aftermath of catastrophic events to construct temporary emergency structures. However, in the absence of adequate environmental control systems, which is a common occurrence in post-disaster scenarios, these structures often result in suboptimal indoor thermal conditions, particularly in hot climates. This can have a detrimental impact on the physical and mental well-being of occupants if they are to be inhabited for extended periods. In such contexts, passive cooling techniques are regarded as the preferred strategy for enhancing the indoor thermal environment. Sarmento, R. et al. [22] stated that in emergencies, providing rapid access to temporary housing for displaced people is essential for effective disaster response. The efficient management of time is, therefore, crucial in addressing the immediate physical needs of the population and fostering a sense of stability.

Hu et al. [24] identified the determination of optimal exterior wall parameters as a significant challenge in the field of lightweight modular integrated constructions (LMICs), with the objective being to minimize life-cycle energy consumption, economic cost, and environmental impact. Research into active thermal protection is closely related to the design of the indoor environment; for this reason, our research activities also focus on assessing indoor air quality and recovering heat and cold from indoor exhaust air. We have described these topics in several publications [59,60,61].

In light of the preceding research, which was chiefly conducted on experimental houses [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16], it can be concluded that energy multifunctional facades (EMFs) are a viable solution to the issue of climate change and an effective means of decarbonization in the construction industry. The multifunctionality of active thermal protection (ATP) in building structures, as an internal source of heat and cooling, enables a degree of flexibility in response to sudden and long-term climate changes that are not possible with conventional building envelopes. This renders energy multifunctional facades applicable within virtually any climate zone or building typology without any discernible restriction.

The strengths, weaknesses, opportunities, and threats associated with the development, research, and implementation of energy multifunctional facades are presented in the SWOT analysis, as shown in Figure 17.

5. Conclusions

This paper outlines the developmental process of a prototype experimental module that will be utilized in the research on energy multifunctional facades. Although the experimental object in situ is still under construction, the results required for empirical verification of the assumptions obtained through analysis and synthesis of the outputs from parametric studies and computer simulations are not yet available. The design of heat/cooling sources and energy systems in BIM is not yet complete. It is therefore considered important to inform the professional public and scientists working in this field of research about the theoretical results, hypotheses, and the anticipated technological procedure for implementing EMFs in real buildings.

The primary objective of this project is to design structures using consistent, prefabricated components (facade, wall, and roof panels) equipped with integrated energy-active elements. The implementation of these elements in conjunction with the building envelope aims to facilitate the integration of heat/cooling source elements (solar collectors or ambient energy collectors for heat pumps) and end components of energy systems for heating, cooling, and thermal barrier. The multifunctionality of these prefabricated elements will be complemented by photovoltaic elements for electricity generation and ventilation with heat recovery, ensuring high environmental safety of the building’s energy systems and, in some cases, its self-sufficiency. This will contribute to achieving carbon neutrality, maintaining a healthy indoor environment, and promoting sustainability.

All of this represents access to affordable, reliable, sustainable, and modern energy for all, as well as solutions for buildings that actively respond to climate change. An important aspect of our innovative solution is the controlled transfer of heat through building structures by means of active thermal protection, which is an effective measure in the fight against climate change and its consequences.

Following the conduction of experimental measurements and the validation of theoretical assumptions, the results and findings will be disseminated to the relevant professional audience.