Climate-Conscious Sustainable Practices in the Romanian Building Sector

Abstract

Climate change refers to a significant and measurable alteration in the climate’s state, evident through shifts in the average and variability of key climate factors. Although the onset of climate change spans several decades, recent studies reveal a concerning intensification that is increasingly driven by anthropogenic activities, with the construction sector emerging as a significant contributor. The present paper investigates climate-conscious innovations within Romania’s construction industry, with a specific focus on the implementation of adaptive strategies. Through a narrative review methodology, this study synthesizes diverse sources, including scientific literature, technical reports, urban policy documents and relevant websites, to map the integration of sustainable construction practices in response to climate pressures. The findings highlight a range of local approaches, including passive design, green infrastructure, and reversible architecture, reflecting Romania’s gradual alignment with broader European environmental objectives. Despite Romania’s relatively low green contribution on a global scale, the country faces significant climate risks, including heatwaves, intense rainfall, and droughts. This evolving climate context necessitates a comprehensive adaptation of architectural practices, construction processes, material selection, and design strategies to mitigate environmental impact and enhance resilience. However, the narrative review approach has inherent limitations, including the potential for selection bias and limited replicability, which constrain the generalizability of the findings. Future research should employ quantitative and empirical methods to validate the effectiveness of climate-adaptive measures in structural engineering. Key areas include the integration of climate-resilient materials, structural performance under climate-induced stressors, and lifecycle carbon assessments of building components. Additionally, further investigation is needed into the development of predictive simulation models that assess the long-term structural impacts of evolving climate scenarios specific to Romania’s geographic and climatic conditions.

1. Introduction

Climate change has emerged as one of the most urgent concerns of our era, with buildings constituting a significant source of greenhouse gas emissions (GHG) [1]. Human activity is evidently affecting the climate, since recent GHGs have reached unprecedented levels [2]. Because the increasing temperatures brought on by climate change are linked to mortality, dehydration, heat exhaustion, and heat stroke, they represent a serious risk to health and safety, especially in the construction industry [3,4].

Since 2015, urban areas have been responsible for the largest proportion of GHG emissions, initially at 61.8% [5]. This contribution has steadily increased over time, now comprising approximately 70% of total emissions [6]. Carbon dioxide (CO₂) is the leading factor behind global warming and the acidification of oceans, contributing roughly 66% to the warming effect from human-generated GHGs, a proportion that exceeds the combined contribution of all other gases [7].

The building sector is a significant source of GHG emissions, primarily from energy consumption for heating and electricity use. Major GHG sources in this sector include CO₂ emissions from electricity usage, as well as methane (CH₄) emissions from heating systems. Construction activities, such as cement production, steel manufacturing, and waste decomposition from demolition, also contribute significantly to CO₂ and CH₄ emissions. These combined factors make the building sector a key area for targeted mitigation strategies to reduce overall GHG emissions [8].

Additionally, the proportion of global GHG emissions originating from urban areas is expected to rise steadily, potentially surpassing 80% by the century’s end in certain projections. Across different scenarios, urban regions in Asia, the Developing Pacific, and Developed Countries have contributed between 65.0% and 73.3% of the total urban consumption-based emissions from 2020 to 2100 [5].

The effects of climate change vary across cities, influenced by their geographical context. Numerous urban centers are already grappling with diverse climate-related challenges. For instance, some cities face increasingly frequent and prolonged heatwaves, exacerbating the urban heat island effect, where cities are warmer than their surrounding areas. Additionally, many urban regions struggle with recurrent flooding from intense rainfall, overwhelming existing drainage systems. In other cases, the loss of wetlands and forests, which previously absorbed rainwater, has intensified flooding issues [9].

Assessments carried out in Romania on climate change reveal that its contribution to the increase in GHGs is low, especially in the context of deindustrialization, i.e., 0.3% at the global level and less than 3% at the European Union (EU) level. According to the fourth biennial report, since 2018, the main sectors that have contributed to the increase in emissions are energy (66.32%), agriculture (17.1%), industry (11.58%), and waste (5%) [10].

The ten-year period from 2015 stands out as the warmest consecutive stretch in meteorological history. During this time, numerous extreme events occurred, impacting millions of individuals and resulting in significant damage. These events encompassed both cold-season occurrences, characterized by inadequate snowfall in agricultural regions, and warm-season phenomena, featuring prolonged droughts punctuated by abrupt and intense instances of instability. These disruptions, at times violent, inflicted considerable harm, including in densely populated urban areas. In 2022, the National Meteorological Administration (ANM) issued a total of 130 messages, including 8 informational messages, 79 yellow code warnings, 38 orange code warnings, and 5 code red warnings. Throughout the year, there were 2997 messages warning of immediate dangerous meteorological phenomena. Among these, there were 2214 code yellow warnings, 688 code orange warnings, and 95 code red warnings [11].

The Intergovernmental Panel on Climate Change Synthesis Report on Climate Change 2023 predicts a change in precipitation patterns for Romania. Winters are projected to become wetter while summers will become drier. Some areas in the east and southwest have already shown decreasing rainfall trends, with occasional heavy downpours leading to local flash floods becoming more frequent. Romania is grappling with the impacts of global warming, including increased thermal stress exacerbated by urban heat islands and more intense short-term precipitation events [12]. These changes are linked to various natural hazards such as floods, landslides, hurricanes, droughts, extreme temperatures, and even earthquakes. These changes are linked to various natural hazards, such as floods, landslides, hurricanes, droughts, extreme temperatures, and even earthquakes. Climate change poses challenges to quality of life, economic stability, social services, and various economic sectors [13].

Addressing the issue of climate change requires reducing GHGs [14]. Carbon emission management in the construction sector focuses on systematically reducing CO₂ and other GHGs emitted during different phases of construction. This approach includes the implementation of strategies to minimize carbon footprints, such as utilizing low-carbon materials, enhancing energy efficiency, and following sustainable construction methods [15].

The present research aims to explore the current state and development of climate-conscious construction practices in Romania, with a particular emphasis on urban adaptation and emission reduction strategies. This study addresses a notable gap in the existing literature by offering a structured and comprehensive account of how Romania is responding to climate-related challenges in the construction sector, a theme that has not yet been comprehensively examined in the scientific literature. Specifically, the research examines how environmental, architectural, and technological solutions are being deployed within a local context. A distinctive contribution of this paper lies in its synthesis of real-world examples, urban initiatives, and local policy responses, based predominantly on secondary sources. To the best of the author’s knowledge, this is the first study to systematically map Romania’s climate-conscious construction efforts, offering practical insights that may inform both academic understanding and policy development in similar contexts.

2. Methodology of Research

The present paper adopts a narrative review approach, designed to synthesize and critically evaluate existing case studies and local practices relevant to sustainable urban development and climate adaptation within Romanian areas. The narrative review methodology was selected for its flexibility and its ability to integrate multiple data sources, such as official reports, technical documents, scientific studies, and journalistic insights, which help provide a comprehensive understanding of the current state of sustainable urban initiatives in Romania. This approach not only enables the synthesis of a broad range of practices but also allows for the identification of patterns and emerging trends in urban sustainability within a local context.

The paper is structured to provide a detailed review of the Romanian landscape of urban sustainability. Each chapter opens with a general overview, grounded in recent primary sources such as original research articles or reviews and policy reports. The focus then shifts to Romanian case studies in subsequent subsections, drawing on secondary data, publicly accessible information, and specific examples from local projects. The intention is to highlight how global concepts and strategies are being applied, adapted, or modified within Romanian cities.

The data collection process for this review involved extensive searches on institutional websites, digital archives, and open-access databases to identify the most relevant sources. Emphasis was placed on projects and initiatives that align with international sustainability standards.

The selection criteria for including examples of Romanian practice in this review were based on three key factors: first, the project or initiative had to be implemented or planned within an urban context in Romania; second, it must address at least one component related to sustainability, climate adaptation, or architectural reuse; and third, there needed to be publicly accessible and verifiable documentation that outlines the initiative’s scope, objectives, and expected outcomes. These criteria ensured that only relevant, transparent, and impactful examples were included in the analysis.

The data assessed for the integration of sustainability strategies was then grouped into thematic categories based on the overarching environmental or technological strategy, allowing for the identification of key trends such as durable and adaptive design, reversible architecture, smart water management, and urban cooling techniques.

Although the number of peer-reviewed scientific articles on Romania’s sustainable urban initiatives is relatively limited, valuable insights were obtained from secondary sources. These included Romanian urban planning documents and policy reports from both local and national authorities, press releases, public project websites, and details of municipal initiatives that highlight ongoing and completed projects. Additionally, web-based references, despite some being harder to access, played a crucial role in offering an understanding of the progress and development of local sustainability efforts.

The literature review was conducted using internet documents and academic databases, primarily ScienceDirect and Google Scholar. A range of search terms were employed, including ‘climate change AND construction sector’, ‘climate change mitigation’, ‘adaptive architecture’, ‘construction sector’, ‘greenhous gas emission’, ‘green building’, ‘future climate projections’, ‘passive design’, ‘energy efficiency in buildings’, ‘smart materials’, ‘biophilic design’, ‘smart water management’, ‘reversible design’, ‘circular economy AND construction sector’, and ‘retrofitting’. These keywords were explored individually as well as in combination with the Boolean operator AND alongside the term ‘Romania’ in order to refine the results and focus on region-specific insights related to climate-conscious construction strategies.

Climate Policy Framework in Romania

To provide a clear and structured overview of Romania’s commitment to climate-conscious policies relevant to the building sector, a chronological policy timeline is presented in

Table 1. Chronological timeline of climate-conscious policies and strategies in Romania.

Year	Policy Name	Description	Ref
1992	Ratification of UNFCCC	Romania signed the UNFCCC, committing to international efforts to combat climate change (by Law No. 24/1994)	[16]
2001	Ratification of the Kyoto Protocol	Romania as an Annex I Party to ratify the Kyoto Protocol (by Law No. 3/2001), committing to an 8% reduction in GHG emissions from 1989 levels during the first commitment period (2008–2012)	[17,18,19]
2005	National Strategy and Action Plan on Climate Change	Developed during Romania’s EU accession process, this strategy aimed to align national policies with EU climate objectives	[20,21]
2013	National Climate Change Strategy (2013–2020)	Aimed to reduce GHG emissions and integrate climate considerations into sectoral policies	[22]
2015	Climate Change and Low-Carbon Green Growth Program	Assisted Romania in developing a comprehensive climate change and low-carbon development strategy, integrating climate actions into EU-funded programs	[23]
2017	Ratification of the Paris Agreement	Romania ratified the Paris Agreement through Law No. 57/2017, which entered into force on 1 June 2017. The agreement, adopted by 196 parties at COP21 in Paris, aims to limit global temperature rise to well below 2 °C above pre-industrial levels, with efforts to cap it at 1.5 °C.	[24,25]
2020	European Green Deal Alignment	Romania aligned its national policies with the EU’s European Green Deal, aiming for climate neutrality by 2050	[26]
2021	Integrated National Energy and Climate Plan (NECP) 2021–2030	Outlines Romania’s strategy to meet EU climate and energy targets, focusing on decarbonization, energy efficiency, and renewable energy integration	[27]
2023	Long-Term Strategy for Reducing Greenhouse Gas Emissions	Sets Romania’s vision for achieving climate neutrality by 2050, detailing sectoral pathways and measures. The national strategy aims to decarbonize the building sector through energy-efficient technologies, increased renovation rates, electrification, heat pumps, and renewable energy integration	[28]
2024	National Strategy on Adaptation to Climate Change (2024–2030)	Aims to enhance Romania’s adaptive capacity and resilience to climate variability and change, facilitating a transition to a sustainable, low-carbon economy	[29]
2024	National Strategy for Disaster Risk Reduction (2024–2035)	Provides a framework to mobilize public and private actors to increase Romania’s disaster resilience, focusing on understanding disaster risk and strengthening risk governance	[30]

UNFCCC, United Nations Framework Convention on Climate Change; GHG, greenhouse gas; EU, European Union; COP21, 21st Conference of the Parties.

. This table synthesizes Romania’s major national and international climate strategies, legal ratifications, and policy frameworks from 1992 to the present, highlighting the country’s evolving approach to climate adaptation and sustainable development. The timeline reflects Romania’s openness to global climate governance and its dedicated efforts to aligning national policies with European and international climate objectives. This policy evolution provides the framework for the Romanian practices presented in this study.

Romania presents a notable climate paradox: despite its relatively low greenhouse gas emissions (i.e., 6.0 metric tons CO₂ equivalent per capita in 2021, below the EU average), its vulnerability to climate change impacts is disproportionately high. The country’s low emissions are largely the result of its economic transition after 1990, which led to a decline in heavy industry and growth in renewable energy. However, Romania faces increasing exposure to extreme weather events such as heatwaves, floods, and droughts that challenge its infrastructure, agriculture, and urban systems. This paradox highlights that low emissions alone do not guarantee resilience, emphasizing the need for integrated strategies that combine mitigation with strong adaptive measures [31,32].

The Romanian experience offers valuable lessons for emerging economies confronting similar dilemmas. First, it shows the importance of aligning decarbonization efforts with targeted adaptation policies that address local climate vulnerabilities. Romania’s progressive legal frameworks and climate strategies demonstrate how national policies can integrate both emission reduction and resilience building, providing a model for countries balancing development and climate risks. Second, Romania’s approach illustrates the benefits of leveraging economic transitions to promote renewable energy and sustainable urban development, enabling simultaneous progress on mitigation and adaptation. Lastly, the country’s use of localized climate data and impact monitoring supports informed decision-making, an essential practice for emerging economies with limited resources. These insights underscore that sustainable development requires synchronized action on both emission reduction and climate resilience [32].

3. The Impact of the Built Environment on Accelerating Global Warming: Climate-Responsive Architecture

Historically, the construction sector has been characterized by energy-intensive practices, resulting in significant carbon emissions throughout the construction lifecycle. These emissions (from various stages, including the energy-intensive manufacturing of building materials, their transportation, and on-site energy consumption during construction and operation) have collectively generated a substantial carbon footprint with far-reaching environmental consequences [33,34].

In terms of the impact of climate change on buildings and the built environment, the building sector plays a major role in contributing to anthropogenic climate change. The energy required for the construction processes and operation of buildings is largely provided by the combustion of fossil fuels, which generates GHGs [35,36].

The effects of climate change have a particular impact on infrastructure and buildings, in particular because of their long lifespan, the cost of construction and maintenance, and their contribution to the smooth functioning of the economy and society. At the building scale, impacts include occupant comfort, health, structural integrity, envelope integrity, and technological systems. On a larger scale, there are broader social and economic implications, from food security to migration and unemployment rates [37].

The construction industry faces a pivotal moment influenced by the pressing challenges of climate change. This realization has deeply impacted the sector: not only does construction contribute substantially to the climate crisis through energy-intensive processes and material consumption, but it also suffers the consequences of climate change. On one hand, the industry emits GHGs and faces carbon taxes on building material production, as well as energy and heat supply during building use [38]. Additionally, it must align with infrastructure and decarbonization goals. A crucial aspect of achieving climate neutrality by 2050, a key aim of the European Green Deal, hinges on the construction sector’s transformation [39].

A building’s carbon footprint begins before use, during the extraction and transportation of materials, and extends beyond dismantling, requiring waste management through reuse, recycling, or disposal. Many construction materials, like steel and aluminum, have significant CO₂ intensity. Steel, for instance, contributes 7% to global CO₂ emissions annually due to its high “embedded energy,” while direct emissions from cement production surged by 1.5 times between 2015 and 2021 [40].

However, the most significant impact on energy usage and emissions occurs during a building’s operation and maintenance phase. According to data from the International Energy Agency in 2021, 18% of a building’s energy consumption stemmed from equipment usage (i.e., appliances and air conditioning), as well as energy demand for water heating, room lighting, and cooking. This demand is on the rise and has exceeded pre-pandemic levels. This energy also goes towards maintaining comfortable temperatures within spaces during both summer and winter, which is increasingly challenging due to global warming [41].

Buildings and infrastructure can be vulnerable to climatic events due to factors such as design or location (in flood-prone areas, steep slopes) or construction defects (use of substandard materials). They may suffer damage or become unsuitable for use due to various extreme or climate change-related weather events, including excessive rainfall, flooding, extreme maximum or minimum temperatures, snowfall, and high winds [42].

4. Architecture Adapted to Climate Change

As the global population continues to grow and urbanization speeds up, Architecture 2030 predicts that the global building stock will double by 2060. The architecture industry is struggling to create structures that will reduce carbon emissions, resist future disasters, and ensure human existence, so this spike in demand comes at a critical time. Global warming presents humanity with two major challenges: the urgent need to drastically reduce GHGs to stabilize atmospheric concentrations and prevent further human-induced climate impacts while also adapting to the effects of climate change, which are already visible and inevitable due to the climate system’s inertia, regardless of emission reduction efforts. The construction industry directly feels the impacts of climate change. More intense precipitation could cause delays and higher costs, while shifts in weather patterns may alter traditional building seasons. The increased frequency of extreme weather events suggests a greater need for rebuilding and repair work [43,44].

Adaptable architectural design addresses pressing planetary issues, including environmental degradation, resource scarcity, and ecological decline. Climate-related concerns are generally approached through two primary strategies, namely resilience building (i.e., adaptation) and impact reduction (i.e., mitigation) [45]. Utilizing natural ventilation in an adaptive manner can alleviate heat-related discomfort by over a half. Adjusting indoor temperature thresholds based on environmental conditions may cut overall energy use by up to one-third. Such adaptive techniques offer notable advantages, especially when applied to heritage structures [46].

Architects play a crucial role in advancing sustainable construction by integrating both climate adaptation and mitigation into design. Their efforts aim to lower embodied carbon, improve energy performance, and develop resilient buildings suited to evolving environmental conditions. While some construction tasks rely on short-term weather forecasts, long-term planning must also consider broader climate uncertainties [47].

One challenge lies in recognizing that buildings have long lifespans unlike consumer goods, continuously consuming energy and emitting CO₂ throughout their lives [48]. The impacts of buildings throughout their lifecycle are interconnected, so while stricter energy-saving standards during construction may result in higher embodied carbon emissions, operational emissions can be reduced. However, energy-efficient buildings may not always save energy or be carbon neutral [49,50]. Conducting a lifecycle carbon analysis enables the assessment of total carbon emissions, considering both operational and embodied emissions over the building’s lifetime and informing policy implications.

Designing buildings to accommodate climate change helps in achieving zero impact by enabling them to adapt without the need for redesign or reconstruction. These strategies may involve the use of flood-resistant materials and the implementation of drainage plans, the creation of landscaping with shade and drought-tolerant vegetation, and the incorporation of passive cooling techniques, improved foundations, and careful vegetation planning to avoid obstructing biodiversity corridors. Buildings should be resistant to wind, earthquakes, and flooding, and their envelope should prevent heat loss and overheating, ensuring a healthy living environment. This adaptation involves passive design adapted to climate change, energy efficiency, using sustainable materials and smart technologies, the supply of local materials, biophilic design, adaptive design, intelligent management of water, modular buildings, regenerative architecture, reversible building, rehabilitation, adaptive reuse of buildings, adaptation of building codes and regulations, the inclusion of cool places and cool spots, and the “renaturing” of cities [51,52,53,54,55,56].

In recent years, Romania has experienced increasingly erratic and extreme weather patterns that reflect the broader trajectory of global climate instability. Data collected by the ANM confirms a rise in temperature anomalies and intensified weather events affecting all major regions of the country. Prolonged heatwaves, unexpected spring frosts, and extreme precipitation events, including flash floods and severe hailstorms, have become more frequent and disruptive. These climatic irregularities have exerted pressure on agricultural productivity, public infrastructure, and the built environment. The nationwide scale of these challenges reinforces the urgent necessity for climate-adaptive strategies within the architectural and construction sectors. The temperature records and extreme weather in counties such as Bihor, Cluj, Satu Mare, and Mureș illustrate the tangible impacts of climate volatility, providing a basis for evaluating responsive architectural interventions (Figure 1) [11].

4.1. Passive Design Adapted to Climate Change and Energy-Efficient Buildings

Passive energy-saving strategies are gaining increasing attention within urban climate research. Findings indicate a bidirectional relationship, where urbanization not only responds to but also significantly drives global climate change and the urban heat island effect. This dynamic presents a substantial challenge in moderating localized climatic extremes while simultaneously enhancing the energy resilience of urban buildings [57].

Passive design is a fundamental component of sustainable architecture, utilizing natural elements and principles to enhance energy efficiency within buildings. In contrast to active systems that require mechanical or electronic interventions, passive design capitalizes on the intrinsic characteristics of the site, climate, and materials to achieve comfortable and energy-efficient environments. Passive design employs materials with high thermal mass, such as concrete or stone, to absorb, store, and gradually release thermal energy. This process mitigates indoor temperature fluctuations, particularly in regions with variable climate conditions. Additionally, optimizing window placement and design enhances natural daylighting, thereby reducing the dependence on artificial lighting. This strategy not only lowers energy consumption but also contributes to improved occupant well-being and productivity [58].

Passive houses stand as a stringent benchmark for energy efficiency in buildings, striving to diminish their environmental footprint while ensuring occupants’ utmost comfort. Their foundation lies in achieving remarkably low energy consumption through passive strategies like insulation and airtight construction, rather than heavy reliance on active heating or cooling systems. It relies on key passive strategies: high insulation, airtight construction, high-performance windows and doors, balanced ventilation with heat recovery, and optimized solar orientation [59,60,61,62]. Figure 2 depicts the five key principles of a passive house, a building standard focused on energy efficiency and minimizing environmental impact.

Buildings can use a mix of materials and construction methods like thermal-efficient glazing, insulation, and eco-friendly structural systems. These principles complement each other synergistically, culminating in buildings that demand minimal energy for temperature regulation. Consequently, occupants enjoy substantial cost savings while contributing to a diminished environmental impact [63,64,65].

The European Green Deal outlines the EU’s commitment to achieving climate neutrality by 2050. Climate change and environmental degradation pose existential threats to Europe and the world. The European Green Deal envisages achieving the goal of carbon neutrality by 2050 by transforming the EU economy into a modern zero-emission economy with resource-decoupled, inclusive growth that is free from social and national inequalities and vulnerabilities [66].

Living, restorative, and regenerative buildings achieve net zero energy if the building’s energy needs are met from alternative/renewable sources. These sources may include photovoltaics, wind turbines, or hydrogen fuel cells. Sustaining net zero energy requires rigorous preventive maintenance of all systems, detailed operations and management plans, and knowledgeable maintenance staff. Continuously monitoring building operations, maintenance, and performance through benchmarking is essential for effective preventive maintenance [67].

The Sustainable Energy and Climate Action Plan for the Municipality of Oradea and the Oradea Metropolitan Area, covering the period 2021–2027, examines energy consumption patterns and outlines strategies to decrease reliance on non-renewable energy sources while promoting the development of facilities for renewable energy production [68].

In the past fifty years, the rapid pace of global urbanization has given rise to significant challenges concerning the sourcing of raw materials and energy for building construction, as well as the management of waste generated throughout the production, usage, and disposal of materials. For instance, the production of cement alone contributes to 8% of the total global emissions of human-induced greenhouse gases, according to the World Resources Institute [69]. Currently, the construction sector accounts for 40% of materials used, waste generated, and energy consumed in the European Union. This overreliance on resources leads to severe societal problems and consequences, evident in phenomena such as global warming, drought, pollution, extensive deforestation, and the accumulation of waste. Unfortunately, these phenomena have become all too familiar aspects of our daily lives [70].

As climate-related challenges intensify globally, Romania, like many countries, finds itself increasingly compelled to translate climate resilience strategies into built form. While the general principles of climate-adaptive architecture are well established, their application at the national and regional levels demands context-specific interpretations. In recent years, several Romanian initiatives have emerged as notable examples of climate-conscious design, emphasizing energy efficiency, sustainable material use, and disaster-resilient structures. These projects not only illustrate Romania’s alignment with broader environmental goals but also highlight the critical role of architecture in shaping adaptive responses to the country’s shifting climate profile. The following section explores exemplary approaches, focusing on the architectural sector’s efforts to respond to escalating climate stressors within Romania’s diverse geographical and climatic landscape.

Implementation of Passive Design Principles in Romania

Romania has seen a gradual emergence of buildings incorporating passive design principles adapted to the local climate context. These developments reflect not only a growing awareness of environmental responsibility but also an effort to align with European energy efficiency standards.

A notable example of climate-responsive public architecture is the Town Hall in Oșorhei, Bihor County, which achieves near-total energy independence through environmentally conscious design. The building’s spatial configuration, advanced thermal insulation, and strategic use of daylight contribute to its sustainable performance. Solar panels installed on the roof provide both electrical and thermal outputs, enabling bidirectional interaction with the national power grid and supplying excess energy during low-demand intervals and accessing it during peak usage. This integrative energy approach greatly diminishes dependency on traditional energy sources. Furthermore, the project benefited from transnational collaboration, particularly with a Hungarian locality well-versed in comparable sustainable practices. Beyond lowering operational expenditures, this initiative presents a scalable model for municipalities seeking to integrate renewable technologies into civic infrastructure [71].

EvoHouse represents a pioneering milestone in Romania’s sustainable construction landscape, being the first officially certified passive house in the country. Developed in 2014 through a multinational collaboration, the building was assembled using cross-laminated timber and modular prefabricated components. Its flexible interior configuration was specifically designed to accommodate evolving spatial requirements, a critical attribute in the context of increasingly unpredictable climatic dynamics [72]. The structure spans 130 m² and is assembled from solid wood panels fabricated off-site, significantly reducing on-site waste and construction time. The heating energy demand averages around 15 kWh/m² annually, while thermal transmittance values (U) remain consistently below 0.15 W/m²K. Indoor temperatures are passively regulated, with fluctuations limited to ±1 °C across seasons. Compared to conventional building methods, the construction time was cut by over 40%, while operational energy expenses dropped by an estimated 60%. The higher upfront costs—roughly 12% above standard builds—are offset over time, with projected payback in under 10 years due to energy savings alone. Beyond performance metrics, EvoHouse revealed key implementation challenges. Transporting oversized prefabricated wall panels through local infrastructure demanded route adaptations and customized logistics planning. Additionally, Romanian building codes lacked clear integration pathways for passive house standards, requiring proactive collaboration with local authorities for compliance. Despite these barriers, the project succeeded in aligning advanced building science with regional limitations. The environmental impact is also notable: the timber structure stores over 15 tonnes of CO₂, while annual emissions are cut by more than 3 tonnes compared to a conventional home of similar size. It is important to acknowledge data that emphasize that prefabricated systems, when properly adapted, can offer a scalable, low-carbon alternative for future housing. This case also demonstrates that passive design, though initially more costly, yields long-term economic and ecological value. As demand grows for sustainable living spaces in Eastern Europe, EvoHouse serves as a replicable benchmark for integrating efficiency, comfort, and speed within residential development [72,73].

Acknowledged as Romania’s leading example of passive energy-efficient architecture, the RIA house is also positioned among the global top three in this category. Endorsed by the Passive House Institute in Darmstadt, this residence demonstrates remarkable thermal performance. Engineered through a prefabrication process by Biobuilds, this dwelling underscores the country’s growing expertise in the development of low-impact, sustainable residential solutions [74]. Achieving an annual thermal energy consumption of just 2 kWh/m²—a 99% reduction compared to the national average of roughly 250 kWh/m²/year—demonstrates a transformative leap in building performance. This dramatic reduction translates into extremely low operational costs, with heating and cooling expenses amounting to approximately 18 RON annually for the 360 m² dwelling, effectively minimizing the homeowner’s carbon footprint and energy dependency. The RIA house required 15–20% higher upfront costs due to advanced materials and systems. Limited local expertise in passive house design necessitated extensive training and close teamwork. Building codes were not fully adapted, causing permit delays. Integrating renewable energy with efficient use demanded careful planning to prevent inefficiencies. Despite higher initial costs, the project proved that significant long-term energy savings and carbon reduction are achievable. Early integrated design and stakeholder collaboration ensured success. This experience highlights the need for updated regulations and capacity building in Romania, establishing a replicable model for energy-positive homes [75].

Buhnici house represents a pioneering model in Eastern Europe, being the first high-end passive dwelling in the region to attain this certification. Erected in just seven months, the building incorporates a sophisticated energy infrastructure, including geothermal boreholes, and integrated radiant cooling within structural elements. Its performance surpasses self-sufficiency, generating over triple the amount of energy required for its operation, thus classifying it as an energy-positive structure [76]. The Buhnici house is a premium passive home located in Romania, designed with a strong focus on energy independence and environmental performance. With a total area of approximately 420 m², the building integrates 70 photovoltaic panels with a combined installed capacity of 22 kW, generating over 25 MWh annually—more than triple its own energy demand. This allows the property not only to be self-sufficient but also to feed surplus electricity back into the grid. Its climate control relies on a geothermal heat pump system and mechanical ventilation with heat recovery, maintaining thermal comfort with minimal energy input. Although the initial construction costs were around 25% higher than those of a conventional house, the investment is projected to be recouped within 12 years through significantly reduced utility bills. The project faced notable challenges, including the scarcity of skilled professionals familiar with passive house technologies and the need to navigate local legislation not fully adapted to advanced, energy-positive systems. Nevertheless, the house stands as a clear example that sustainable, high-performance housing is both viable and scalable within the Romanian context, setting a benchmark for future developments in the region [77,78].

The UPB passive house prototype represents an innovative fusion of passive design principles with active mechanical systems, achieving an exceptionally low annual heating demand of approximately 13 kWh/m² and generating about 1556 kWh of photovoltaic energy annually. This remarkable performance is enabled by the combination of an earth–air heat exchanger and a heat pump, which together provide an efficient, sustainable heating and cooling solution. While the initial design phase involved some uncertainties related to system integration and climate responsiveness, ongoing performance monitoring and adaptive management have been essential in addressing these challenges. The iterative feedback from real-time data allows for the continuous optimization of both the building envelope and the energy systems, improving operational reliability and occupant comfort. This data-driven approach underscores the importance of multidisciplinary collaboration among architects, engineers, and technicians to ensure that airtightness, thermal integrity, and smart controls function harmoniously. Moreover, the project highlights typical barriers such as the need for specialized expertise and the higher upfront investment, which can be mitigated by targeted government incentives and international knowledge exchange. By demonstrating a scalable model that balances energy efficiency with renewable generation and adaptive operation, the UPB prototype provides valuable lessons for expanding passive and low-energy building practices within Romania’s diverse climatic context and beyond [79].

A passive villa inspired by Scandinavian architectural principles, located within the Hambar44 residential development (Ilfov county), illustrates how simplicity in form can coexist with advanced thermal performance. By employing geothermal heat pump systems alongside high-performance glazing, the dwelling achieves substantial reductions in energy demand. Heating and domestic hot water costs are lowered by as much as 90%, positioning the residence as a viable and replicable solution for sustainable, energy-efficient housing [80].

In the city of Brașov, the Dwellii initiative introduces a modular residential concept that exemplifies accelerated, scalable green building practices. Fully prefabricated in manufacturing facilities within a month, each unit is assembled on-site in under 24 h. This streamlined process not only curtails material waste but also aligns with passive design standards, offering an economically accessible and ecologically responsible construction solution [81].

In the Oradea Metropolitan Area (ZMO), there are currently no registered wind power plants, and the potential for harnessing wind energy in this region is considered low due to the effectiveness and efficiency challenges posed by the meteorological conditions of Western Romania. Instead, the municipality of Oradea and the metropolitan area boast significant geothermal energy sources, which are actively exploited. These sources provide energy to various public institutions and entities, including the Dr. Gavril Curteanu Municipal Hospital, Antonio Alexe Sports Hall, Nymphaea Thermal Wellness Complex, and North Ioșia Strand [68].

Figure 3 illustrates the different types of renewable energy sources used in the ZMO. There are three main types of renewable energy used in the ZMO: solar energy, biogas, and geothermal energy, each chosen based on the region’s specific natural potential and infrastructural goals. Solar energy is harnessed through the development of photovoltaic parks in several municipalities surrounding Oradea, such as Oșorhei, Borș, Sântion, Sânmartin, Nojorid, and Leș. Within the city itself, a large-scale photovoltaic park has been designed and implemented, containing over 15,000 solar panels and supplying energy to six public buildings. Additional parks have also been installed in Sântandrei and Girișu de Criș. Biogas is utilized through the construction of a thermal power plant in Oradea that operates on biogas, a renewable energy source derived from organic waste decomposition. This plant generates thermal energy (used for heating) and possibly electricity, contributing to the city’s efforts to diversify its energy mix and reduce dependence on fossil fuels. Its implementation marks a key step toward a more circular and sustainable energy system. Furthermore, geothermal energy is one of the most valuable local resources. It is used both in public infrastructure and residential areas, with parts of Oradea benefiting from geothermal water for district heating. A geothermal power plant was also built in the city to enhance the use of this clean energy source, supplying institutions such as the Dr. Gavril Curteanu Municipal Hospital, the Antonio Alexe Sports Hall, and the Nymphaea Thermal Complex [68].

Figure 4 illustrates the distribution of total energy consumption across different categories of public buildings in the Oradea municipality for the reference year 2020. Educational facilities represent the largest share of energy use, followed by healthcare buildings, with social, administrative, and sports facilities accounting for smaller portions. This overview helps identify priority sectors for energy efficiency and potential renewable energy integration [68].

Thermal rehabilitation measures planned for 45 residential buildings in the municipality of Oradea are expected to achieve significant energy savings and emission reductions. These interventions aim to improve the energy efficiency of 1069 apartments, resulting in an estimated 35–40% reduction in energy consumption and at least a 35% decrease in CO₂ emissions. Specifically, projections indicate a 39% reduction in total annual energy consumption—from 28 GWh to 17 GWh—and a decrease in average consumption per apartment from 26,200 kWh to 15,900 kWh. Total energy savings are anticipated to reach approximately 11 GWh per year (Figure 5). Key measures include enhanced external wall and roof insulation, the replacement of windows with high-performance thermal frames, and upgrading heating distribution systems. These improvements are expected to increase indoor comfort, reduce operational costs, and support the environmental sustainability goals outlined in the municipality’s integrated development strategy. The expected outcomes align with targets from the National Action Plan for Energy Efficiency, which forecasts an over 40% reduction in final energy consumption for the residential and tertiary sectors [68].

The municipality of Oradea is undertaking a series of renewable energy and energy efficiency projects aimed at reducing energy consumption and CO₂ emissions across various public infrastructures in Oradea and the ZMO. These initiatives are at different stages of planning and feasibility analysis and reflect a strong commitment to sustainability and environmental responsibility. The projects leverage solar and geothermal energy, as well as improved public lighting systems, to deliver measurable environmental benefits. Figure 6 summarizes the minimum expected reductions in energy consumption and CO₂ emissions for each project [68].

The 26 projects outlined in the Action Plan for Sustainable Energy and Climate for the 2021–2027 period aim to enhance urban planning, energy efficiency, environmental sustainability, and climate resilience in the ZMO. These initiatives focus on extending utility networks (thermal, gas, and water), modernizing and expanding green spaces, and identifying areas vulnerable to climate change. Key efforts target waste management improvements, digital energy mapping of buildings, and public awareness campaigns related to resource use and environmental risks. Other projects include energy-efficient renovation programs for public and residential buildings, the wider use of photovoltaic panels for public lighting, and integrating traffic management systems. The plan also supports the replacement of municipal fleet vehicles with electric ones and improving road infrastructure resilience to extreme temperatures. Significant attention is given to compliance with nearly zero-energy building (nZEB) standards, developing interactive energy consumption maps, and building databases that classify collective housing by energy performance. A strategic initiative aims to establish a low-emission district heating system. These projects are largely in the idea stage, with funding sourced from local budgets, European programs, and other national initiatives. Collectively, they represent a comprehensive and forward-looking approach to urban development and environmental responsibility [68].

In southern Bucharest, Cartierul Solar emerges as a model for reducing operational expenditures and environmental burden through the integration of renewable energy solutions within the residential sector [82].

The Timpuri Noi Square—Phase II project by Vastint Romania reflects a transformative approach to urban regeneration, distinguished as the first office development nationwide to be entirely independent of fossil fuel consumption, aligning with progressive environmental standards [83].

According to updated statistics, by the year 2020, more than 250 constructions across Romania had obtained certification as environmentally sustainable under globally recognized frameworks like the Building Research Establishment Environmental Assessment Method (BREEAM), Leadership in Energy and Environmental Design (LEED), Excellence in Design for Greater Efficiencies, and the WELL Building Standard. This certified stock comprises a range of structures, including business premises, housing complexes, retail developments, and distribution centers, with the highest concentration situated in Bucharest and notable presences also recorded in Cluj-Napoca, Timișoara, and Brașov [84]. Moreover, Romania currently has a total of 11 newly constructed buildings certified with the highest BREEAM rating of “outstanding”, each achieving a score exceeding 90%. Of these, seven were assessed and certified by BuildGreen. In terms of LEED certifications, there are 28 newly built projects in Romania that have achieved the “Platinum” level, indicating advanced sustainability performance. Out of these, eight were certified through BuildGreen [85].

A significant role in promoting energy efficiency among homeowners and real estate developers has been played by government-supported programs managed by the Environmental Fund Administration. Among the most relevant initiatives are the “Green House Plus” and “Energy-Efficient House” programs, which provide funding for energy efficiency projects, and the “Green House Photovoltaic” program, which provides funding for the installation of photovoltaic panels in passive houses, where such systems are not already included in the developer’s base offer [86].

4.2. Smart Materials

Smart materials exhibit distinct behavioral properties in response to external stimuli (i.e., light, stress, moisture, temperature), effectively integrating both sensing and actuation capabilities. The sensor component detects environmental changes and communicates with the actuator, which subsequently alters the material’s characteristics. Recent advancements have led to the emergence of diverse categories, including shape memory alloys, piezoelectric compounds, thermobimetals, and thermochromic substances [87,88]. To diminish the carbon footprint of new construction projects, minimizing the use of high-emission materials like concrete, steel, aluminum, and foam insulation is crucial [88,89].

Sustainable construction materials are designed to ensure reliable performance and durability over time while requiring minimal maintenance and significantly reducing environmental impact through lower raw material extraction, reduced energy consumption, and minimized emissions during both the production and usage phases. A variety of innovative materials are now being integrated into sustainable building practices, each offering distinct advantages. These include autoclaved aerated concrete for its lightweight and insulating properties, geopolymer concrete, which reduces carbon emissions by replacing Portland cement, and hempcrete, a biodegradable material with excellent thermal insulation. Additionally, solutions such as self-repairing concrete, phase change materials, and photocatalytic concrete exemplify smart technologies that enhance longevity, energy efficiency, and environmental performance. Structural innovations like ultra-high-performance concrete, cross-laminated timber, and insulated concrete forms also contribute to reducing the carbon footprint of the built environment, while specialized options such as permeable concrete, Martian concrete, and repurposed wind-turbine blade elements highlight creative pathways toward climate-conscious construction [90].

Nanotechnologies enhance traditional materials with extraordinary properties. An array of nanomaterials, including nanoalumina, nanosilica, nanocellulose, carbon nanotubes, nanoclay, and titanium dioxide, have been investigated for their potential in construction applications. These substances significantly enhance mechanical resilience, thermal behavior, and overall material performance. Their integration contributes to improved durability, an over 20% increase in strength, better insulation, and self-cleaning surface properties [91].

Additionally, immersive technologies such as virtual reality and augmented reality are becoming increasingly vital within the architecture, engineering, and construction industries, given the sector’s fundamental reliance on spatial and three-dimensional visualization [92].

The Internet of Things and 5G technology are expected to revolutionize real-time data monitoring and management, facilitating smarter and safer construction sites. These technologies are digitizing and automating the construction industry, ushering in an era of precision, sustainability, and heightened productivity. Three-dimensional printing, an additive manufacturing technology, constructs three-dimensional models by layering successive material layers. These models are created using 3D printers of various sizes with various purposes, which follow commands from computer-aided design programs. Additionally, 3D scanners can replicate these models. The versatility of 3D printing means that it finds applications across multiple sectors, including medicine, engineering, construction, aerospace, dentistry, industrial design, consumer products, jewelry, and footwear. While 3D printing has been employed in diverse domains, its application in building construction remains relatively novel [93].

Emerging Trends and Romanian Implementation of Smart Materials

In the context of Romania’s construction sector, the application of smart materials is emerging as a significant strategy to enhance building performance, sustainability, and resilience.

Owing to their multifunctional performance and adaptive behavior, smart materials are increasingly viewed as key contributors to environmentally responsible construction methods. Although Romania is progressively embracing these innovative materials, the pace of integration remains constrained by ongoing challenges linked to economic limitations, cultural perceptions, and regulatory frameworks. A noteworthy instance is Fineceramic^®, an internationally patented innovation by Roca, which facilitates the fabrication of refined, ultra-slim ceramic components marked by elevated visual appeal and structural robustness. Produced through physical vapor deposition, this material incorporates titanium-based nanoparticles into its surface, thereby significantly improving its resistance to wear and oxidation, properties of particular importance in sanitary design contexts [94].

Shape memory alloys are metallic materials that can return to a predefined shape when subjected to specific thermal conditions. This property is particularly useful in applications requiring self-healing or adaptive structural components [95]. Romanian research initiatives have explored the integration of shape memory alloys in civil engineering. For instance, the development of smart composite systems incorporating shape memory alloys aims to create self-adjusting structural elements capable of responding to environmental changes, thereby improving the durability and safety of buildings and infrastructure [96].

Electrochromic materials change color or opacity when an electric voltage is applied, while thermochromic materials alter their properties in response to temperature variations. These materials are utilized in windows and facades to regulate light and heat ingress, enhancing energy efficiency and occupant comfort [97]. The Romanian Council for Green Buildings has identified electrochromic and thermochromic windows as innovative solutions for improving building performance. These materials are being incorporated into modern constructions to optimize energy use and reduce environmental impact [98].

Aerogels are ultra-lightweight materials with low thermal conductivity, making them excellent insulators. Their application in construction contributes to enhanced thermal performance without adding significant weight to structures [99]. Romanian construction projects are beginning to incorporate aerogels into building designs, particularly in areas requiring high insulation standards. This adoption aligns with global trends towards sustainable and energy-efficient building practices [98].

Three-dimensionally printed silicone sensors are flexible devices capable of monitoring various parameters such as strain, temperature, and pressure. Their integration into building structures allows for real-time monitoring and adaptive responses to environmental conditions [100]. The NewSmartSil project in Romania focuses on developing 3D-printed silicone sensors for civil engineering applications. These sensors are designed to monitor structural health, enabling proactive maintenance and enhancing the longevity of buildings [101].

Several commercial real estate developments in Bucharest, including The Bridge and Oregon Park, have adopted advanced architectural solutions such as dynamic electrochromic glazing, sustainable building envelopes, and components made from recyclable resources, leading to notable reductions in energy consumption during use [102].

In the domain of residential architecture, Hațeg House exemplifies efficient laminated timber construction, characterized by low embodied energy and superior insulation performance, with construction timelines shortened through modular prefabrication methods [103].

Environmentally responsive insulation technologies, such as hemp-derived systems and hydroceramic composites, have been introduced in sustainable housing projects like Cartierul Solar and Verde Park, where they facilitate passive control of interior thermal and humidity conditions. Despite their advantages, the broader deployment of these technologies remains constrained by substantial upfront investment, insufficient familiarity among industry professionals, and the lack of contemporary regulatory frameworks that support innovative construction materials [82].

4.3. The Supply of Local Materials: The Circular Economy and Off-Site Construction

The construction sector faces increasing demands to transition toward sustainability, embracing circular economy principles. Originating from industrial ecology, this model integrates concepts like the 3Rs (i.e., reduce, reuse, recycle), eco-efficiency, cradle-to-cradle thinking, biomimicry, and zero emissions. It synthesizes diverse frameworks—from industrial symbiosis to green growth—into a cohesive strategy promoting regenerative material cycles and long-term environmental resilience in the built environment [104]. Reaching nearly zero-energy buildings is the main goal when it comes to new construction [105].

Decreasing the distances between material manufacturing and on-site use can significantly impact a project’s footprint and overall building sustainability. Transport distances play a crucial role in determining GHGs due to fuel combustion. Thus, by minimizing these distances, a project can significantly reduce its carbon footprint [106,107].

Modular prefabricated construction, off-site and in a factory-controlled environment, minimizes waste, shortens construction time, increases efficiency, reduces transport emissions, and reduces resource consumption, resulting in 30% less emissions on-site. Additionally, off-site construction provides architects with innovative opportunities to integrate sustainable materials and technologies into the manufacturing process, promoting environmentally friendly construction practice [108].

Examples from Romanian Practice

Romania is slowly integrating circular economy concepts, in line with EU regulations aimed at minimizing environmental harm. Despite obstacles such as insufficient laws, weak enforcement, and low recycling levels, the country is advancing toward a circular model. Key actions focus on waste reduction, enhancing resource use, and fostering eco-friendly production and consumption. Efforts to promote recycling, reuse, and waste reduction are central to Romania’s path to a more sustainable economic framework. Although challenges remain, both national policies and EU assistance are driving a gradual shift toward a more circular, environmentally conscious economy [109,110,111].

In Romania, climate adaptation efforts increasingly emphasize the utilization of locally sourced materials alongside the adoption of circular economy frameworks in the building sector. In regions such as Maramureș, vernacular dwellings have been reimagined through the reuse of sustainably harvested timber, frequently salvaged from deconstructed buildings, adhering to circular construction models [112].

A notable example in Bucharest is the transformation of The Ark, once a commodities exchange, into a contemporary creative center. This retrofit combined heritage conservation with ecological upgrades, employing recycled inputs and energy-saving technologies while retaining the architectural integrity of the original façade [113].

4.4. Biophilic Design

Biophilic design is an integrated approach that combines natural elements, engineering methods, and design strategies to enhance health, well-being, and productivity, as evaluated through individual biometrics, self-reported mood, and work performance [114,115].

Moreover, the biophilic approach is about bringing aspects of the natural world into built spaces, such as natural light, water features, plants, and materials such as wood and stone, with an emphasis on reconnecting with nature, bringing the outdoors indoors by blending natural elements, patterns, and materials into the built environment. By incorporating textures, shadows, colors, and perspectives, biophilic design contributes to mental comfort and increases productivity, reducing reliance on artificial lighting and improving the indoor climate [116].

As urban greening, sustainable design, and green architecture become more prevalent, many cities, infrastructures, and buildings are expected to embrace biophilic design in the coming decades. Buildings that harmonize with the surrounding nature, such as those featuring ivy walls or designs that complement local geological features, are often well received. Additionally, natural shapes and forms, including representations of vegetation, trees, leaves, and animal motifs like beehives and webs, can be integrated both inside and outside buildings. To successfully apply biophilic design, it is essential to adhere to certain basic principles consistently. These principles serve as fundamental conditions for effective biophilic design practice [117,118].

Biophilic Design in Romania Targeting Local Initiatives and Best Practices

In Romanian architectural practice, the integration of biophilic principles has gained traction as a method to promote health-oriented, user-centric environments. An illustrative example is Green Court Bucharest, a project by Skanska, which strategically utilizes vegetated terraces, interior landscaping, dynamic water installations, and expansive glazing to enhance daylight exposure. This development has been awarded BREEAM certification, reflecting its alignment with sustainability standards and its prioritization of occupant health and environmental quality [119].

In the residential sector, the Cosmopolis complex in Bucharest integrates artificial lakes, urban forests, and green roofs to enhance environmental quality and promote human–nature connections [120].

Located centrally in Bucharest, One Cotroceni Park is a major multifunctional real estate development that integrates contemporary office environments with retail infrastructure, designed to enhance both operational efficiency and user well-being through climate-conscious and biophilic design strategies. Among its most prominent nature-integrative components are the extensively vegetated rooftop areas, which provide opportunities for outdoor respite and informal interaction. Within the interior spaces, the generous incorporation of plant life contributes to a tranquil microclimate, supporting cognitive performance and psychological comfort. The use of organic construction materials, particularly untreated wood and natural stone, reinforces sensory connection to the natural world, encouraging a biophysically restorative atmosphere. The architectural layout also prioritizes daylight access through large-scale glazing and open spatial configurations, ensuring that occupants benefit from both abundant natural illumination and unobstructed visual contact with landscaped zones, thereby fostering a healthier and more human-centered built environment [121].

Uptown is a modern residential development in Cluj-Napoca, designed in alignment with nZEB standards, with a strong emphasis on enhancing resident well-being through the integration of biophilic design elements. This project features shared garden areas and private green spaces adjacent to individual units, along with rooftop and terrace-level relaxation zones that promote interaction with natural surroundings. Expansive windows ensure abundant daylight penetration throughout the living spaces, supporting circadian health and reducing the need for artificial lighting. The interior design incorporates natural materials and indoor vegetation, contributing to a soothing, environmentally conscious living environment [122].

4.5. Durable and Adaptive Design

Sustainable architecture aims to reduce environmental impacts by incorporating energy-efficient technologies that enhance the livability, health, well-being, and comfort of inhabitants. This approach involves considering building orientation, natural light, ventilation, shading, and the use of biomass, while focusing on resource efficiency and the reuse of materials from the earliest project phases [105,123].

Green roofs can capture and filter rainwater on-site while providing a habitat for plants and reducing cooling needs in certain climates. Today, scientific research can help spread knowledge about natural materials and traditional construction methods, supporting their proper use. Sustainable architecture focuses on reducing resource use and pollution throughout a building’s lifecycle. Sustainable construction is guided by seven core principles: reducing CO₂ emissions through energy-efficient, low-impact buildings and eco-friendly urban planning; reusing materials via circular economy practices; promoting near-zero-energy buildings using renewables and smart systems; protecting land and biodiversity; designing for climate resilience; enhancing indoor health and well-being; and raising environmental awareness through education and regulation [124].

Romanian Perspectives on Durable and Adaptive Architecture

Durable and adaptive design principles focus on enhancing the longevity, flexibility, and environmental performance of buildings. In Romania, several major developments have embraced this approach, demonstrating how built environments can be resilient, efficient, and responsive to future functional needs.

Situated in the northern area of Bucharest, Floreasca City represents a multifunctional urban development that integrates residential and commercial uses while illustrating contemporary strategies for resilient and adaptable architectural design within the Romanian context. This complex integrates a suite of environmentally responsive technologies that aim to reduce ecological footprints and ensure long-term resource efficiency. Key adaptive components include advanced water management systems alongside a network of green elements such as rooftop vegetation and elevated garden platforms, which collectively aid in moderating local thermal conditions and managing precipitation runoff. The development harnesses solar energy through on-site photovoltaic installations, thereby diminishing reliance on conventional energy grids. Construction materials were selected based on durability and recyclability, in alignment with circular economy principles. Furthermore, the project emphasizes optimized natural illumination through generous window surfaces, supplemented by energy-efficient LED lighting systems to enhance interior comfort while minimizing energy use [125].

Located in Bucharest, the Timpuri Noi Square development exemplifies a multifunctional urban complex that accommodates office, residential, and retail components, with design considerations focused on long-term functional resilience and contextual integration within the existing cityscape. Central to its conception are strategies that prioritize both physical durability and spatial adaptability. Among the most significant features are green rooftop installations that foster ecological diversity and mitigate heat accumulation, along with integrated photovoltaic systems that facilitate the local production of clean energy. Water reuse technologies further support efficient resource utilization. The internal configuration of the buildings has been intentionally designed to permit spatial reorganization, ensuring adaptability to shifting user demands over time. These design strategies are reinforced by a comprehensive sustainability framework, which includes stringent energy efficiency measures, the incorporation of environmentally responsible building materials, and the deployment of advanced waste reduction mechanisms, all contributing to the mitigation of the project’s environmental impact [83].

Situated in the city of Iași, the Palas complex represents a multifunctional urban development that integrates business, residential, retail, and leisure facilities within a sustainability-oriented framework. Central to the project’s environmental strategy is the incorporation of green roof systems, solar energy technologies, and mechanisms for efficient water use, all contributing to improved ecological performance and reduced resource consumption. The spatial design allows for high adaptability, enabling the internal configuration of office and commercial areas to evolve in response to shifting economic and social demands. Moreover, the integrated green infrastructure, which includes stratified planting, artificial water bodies, and conserved heritage structures, reinforces the project’s environmental resilience while simultaneously preserving local cultural identity within the built environment [126].

4.6. Smart Water Management

The growing vulnerability of water resources, exacerbated by climate change, directly impacts both their quality and availability. Addressing these issues requires integrating climate change adaptation approaches into water management practices, ensuring resilience and sustainability [127].

Water management systems, including integrated water resource management, have typically relied on past climate and hydrological data, assuming system behavior remains constant. However, as climate patterns evolve, these assumptions no longer hold, making historical data insufficient for planning future variability and extreme events. Adapting water management strategies to these changing conditions is now necessary [128].

Smart water management technologies leverage sensors and telemetry to provide continuous monitoring of parameters like flow, pressure, and consumption. These systems facilitate the early detection of leaks and overuse, enhancing the efficiency of water distribution. Key solutions include ultrasonic sensors, smart meters, and leak detection tools. Furthermore, the increasing application of digital twins aids in data analysis and resource management optimization. These advancements play a critical role in conserving water and promoting sustainable resource usage [129].

Architects can contribute to water control by integrating rainwater harvesting, water saving and wastewater recycling systems, which can play a positive role in combating climate change, as seasonal rainfall patterns indicate alternating periods of excessive rainfall, leading to flooding, alternating with increasingly long periods of drought. To achieve this objective, buildings need to reduce their dependence on centralized water supply systems by collecting rainwater in their own systems and implementing circular water recycling/reuse systems. With the impacts of climate change, such as rising sea levels, extreme weather events, and temperature fluctuations, architects can design buildings that are adaptive and resilient [130].

While adaptation and mitigation measures can complement each other, they may also present direct conflicts. For example, incorporating large windows to reduce the need for artificial lighting improves daylight utilization but can lead to overheating in summer if not properly shaded. Strategies for addressing these challenges include integrating vernacular architectural techniques to mitigate flood risks and safeguard housing. Another approach is employing adaptive master plans, computational models that generate urban plans based on contextual information, boundary conditions, and design objectives [131].

Romanian Practices Targeting Smart Water Management

Smart water management is a cornerstone of sustainable urban development. It involves the use of digital technologies and ecological strategies to reduce water waste, manage runoff, and optimize water use across facilities.

Palas Iași not only boasts sustainable architectural features but also incorporates advanced water management systems throughout the development. These systems include the collection of rainwater, which is utilized for irrigation in gardens and public green spaces, as well as water-efficient infrastructure integrated into both office and commercial buildings. Additionally, intelligent monitoring technologies are employed to regulate water consumption across the entire complex, ensuring minimized wastage and optimized overall performance [126].

4.7. Reversible Design: Adaptive Reuse and Reuse of Buildings

Reversibility is the ability to change structures or disassemble its components, systems, and products while avoiding destruction [132].

Many of the building materials used today end up as waste when structures are demolished, posing a significant sustainability challenge for architecture. This accounts for nearly 34% of the total waste generated annually in Europe, highlighting the urgent need for reduction. Creating reversible architecture aligns with the principles of a circular economy, aiming to eliminate waste by reusing all materials in a closed-loop system. Designing buildings with reusability in mind ensures that their components can be repurposed for other projects [133,134].

Reversible architecture ensures that entire buildings can be dismantled at the end of their lifespan, with all components reused to avoid waste. These designs envision structures that can be easily added to or removed without causing damage to the building or its materials. Referred to as “Design for Change,” this approach enables flexible buildings that can adapt to evolving market demands and user needs. Reversible design allows structures to adapt to changing needs, allows for changes in functionality or utilization, and focuses on flexibility, adaptability, and the potential for disassembly or modification without the need for complete demolition [132].

Another sustainability strategy involves prioritizing the renovation, reuse, or adaptive reuse of existing structures over demolition and new construction. This approach is not only faster and more cost-effective but also conserves materials and preserves heritage buildings, often protected by local regulations. Traditionally, buildings were designed to fulfill specific needs such as function, comfort, and budget, tailored to prevailing conditions. Sustainable design has shifted this mindset, introducing green building standards and rating systems aimed at creating environmentally conscious buildings. However, emerging innovative concepts challenge conventional notions of building design and sustainability, viewing buildings as dynamic and interactive entities. These include the concepts of adaptive architecture, living buildings, recycling, adaptive regeneration/reuse, computational design, nanotechnology, and the integration of artificial intelligence (AI). Enhanced spatial flexibility enables occupants to utilize floor space more efficiently as needs evolve, while convertibility allows various building areas to serve multiple purposes. Extensibility enables buildings to accommodate higher densities without expanding their footprint or infrastructure. These concepts redefine traditional building paradigms and push the boundaries of sustainable design, emphasizing adaptability and responsiveness to evolving needs and conditions [135,136].

Romanian Practices Targeting Reversible Design

Reversible design emphasizes the ability to modify and adapt buildings over time, allowing them to be repurposed for different functions as the needs of society evolve. This approach is closely related to adaptive reuse, where old structures are given new purposes, contributing to sustainability and heritage preservation. Several urban regeneration projects in Romania showcase these principles, highlighting the growing trend of transforming old industrial sites into modern, multifunctional spaces.

Sema Parc is a transformative urban regeneration project located in Bucharest’s Grozăvești area, where the site of the former Semănătoarea factory is reimagined as a mixed-use complex. This development focuses on adaptive reuse and reversible design, breathing new life into the old industrial structures while preserving their historical integrity. Several former factory buildings have been repurposed into modern office spaces and residential units, showcasing the principles of adaptive reuse. This project is designed with future adaptability in mind, allowing for easy modifications to accommodate evolving community needs, which is a key aspect of its reversible design approach. Additionally, the renovation process incorporated recycled materials from the original structures, minimizing waste and conserving resources. Architecturally, this complex blends contemporary office designs with glass, steel, and high-tech materials, offering expansive terraces and large windows that provide panoramic views of the surrounding green spaces, with 70% of the residential area dedicated to lush, open environments [137].

Halele Obor, a historic marketplace complex in Bucharest, underwent a comprehensive renovation aimed at adaptive reuse, transforming the site into a vibrant hub for commerce and culture. By focusing on the preservation of its original architectural framework, the project employed adaptive reuse techniques to revitalize existing spaces, preserving the complex’s historical integrity while repurposing it for modern functions. Central to the design approach is reversible design, which ensures that the buildings can easily accommodate a variety of future commercial and cultural activities without compromising their structural core. Additionally, sustainability was a priority, with the integration of energy-efficient technologies and advanced water management systems [138].

4.8. Rehabilitation—A Sustainable Strategy for the Preservation of the Built Environment

Building rehabilitation involves improving the habitability, safety, and energy efficiency of existing buildings and revitalizing dilapidated or outdated structures. This concept encompasses various interventions such as repairing structural elements, renovating facades and roofs, reconfiguring interiors, and adapting buildings to new uses. It plays a crucial role in preserving built heritage and revitalizing urban areas. The integration of rehabilitation with sustainability practices is essential to minimize environmental impact and promote eco-friendly construction methods [139,140].

The construction industry has a significant environmental footprint, making building rehabilitation a strategic approach to reducing carbon emissions. It emphasizes the reuse of materials and adoption of efficient technologies, thus lessening resource consumption and waste generation. Beyond environmental benefits, rehabilitation preserves historical legacy and revitalizes urban neighborhoods, offering new opportunities for development [141].

Rehabilitation projects should not only focus on energy efficiency but also add value to modernized buildings. They involve less resource consumption and waste generation compared to new construction, provided that modern construction techniques and sustainable materials are utilized. Adhering to evolving building standards and regulations, including those related to energy efficiency and environmental performance, is crucial in this process. Retrofitting, a common practice in building rehabilitation, aims to enhance energy efficiency and thermal performance or update outdated structures. Prioritizing the improvement of existing buildings over demolition helps retain materials and reduces carbon emissions associated with new construction. This approach aligns with sustainability goals and promotes responsible stewardship of resources [142].

Romanian Practices Targeting Retrofitting Concepts

Since 2013, the University of Oradea has implemented a transformation plan focused on sustainability, with retrofitting and circular economy principles at its core. The aim was to reuse existing infrastructure and reduce environmental impacts. Key retrofitting techniques included structural rehabilitation, thermal insulation, utility system replacement, and the integration of renewable energy systems. Seven previously abandoned buildings (over 5,400 sqm) were reintegrated as educational spaces, equipped with photovoltaic panels, which are efficient heating and ventilation systems. The heating system was reconfigured to use geothermal energy as the primary source, supported by high-efficiency heat exchangers and pumps, with solar power as a supplement. A closed-loop system reinjects residual geothermal water, increasing resource efficiency. Moreover, additional upgrades included the rehabilitation of water and sewage networks, rainwater harvesting systems for irrigation, and smart metering for energy and water use. The campus also improved green space through the removal of obsolete buildings and introduced sustainable mobility options like bike racks, pedestrian zones, and a tram extension [143,144].

5. Measures That Can Be Applied in Landscape and Infrastructure

Technology transfer is essential for climate-conscious developments in the building sector, facilitating access to sustainable materials and innovative construction techniques that diminish carbon emissions [145]. The Quadruple Helix concept, which encompasses collaboration among academics, industry, government, and civil society, enhances innovation by merging local knowledge with sophisticated technologies to achieve sustainable solutions [146]. This collaboration fosters the development of a climate-resilient ecosystem by implementing technologies that improve energy efficiency and resource conservation [147].

Urban systems contribute to the exponential rise in emission levels, but this process can be slowed or, optimistically, reversed by promoting development that fully aligns with environmental protection. Architects can contribute by designing eco-friendly buildings with green roofs and living walls, integrating green spaces, and using materials or technologies that reduce the negative impact on people and buildings [148].

In Romania, various urban areas have adopted innovative measures to mitigate the urban heat island effect and improve the thermal comfort of residents. Among these solutions, the integration of water features such as fountains and artificial lakes plays a crucial role in reducing ambient temperatures. Nicolae Romanescu Park in Craiova [149] and Central Park in Cluj-Napoca utilize lakes and fountains to create cooler microclimates. These “cool spots” offer natural thermal regulation through the strategic use of water. Additionally, urban green space initiatives like the “Green Cluj” project [150] and Timișoara’s “Green City” action plan are focused on expanding green areas and enhancing air quality [151]. These projects include the creation of green corridors and planting trees to combat heatwaves while also improving urban aesthetics and resilience to climate change. Furthermore, re-establishing forest protection belts around agricultural land and renaturation efforts, such as those in Tulcea, contribute to enhancing biodiversity, preventing soil erosion, and preserving moisture levels, thereby promoting a healthier urban environment [152].

Water features such as pools, artesian fountains, sprinklers, and ponds can be utilized to enhance thermal comfort in outdoor spaces. Oradea benefits from ten artesian wells situated in the central and pericentral areas. Currently, development works are ongoing in public areas above the underground parking lot on Independentei Street. This includes the construction of an artesian fountain with a waterfall-like effect, featuring water steps. The fountain is one of four artesian fountains located in Piata Unirii, Oradea. Utilizing vegetation curtains planted in all available urban spaces can effectively reduce temperatures and provide shaded areas. In 2023, the city of Oradea initiated a municipal campaign that resulted in the planting of 790 trees across various species, alongside an additional 100 birch trees as part of the “ Plant in remembrance” project, in collaboration with the Zi de Bine Association. The 2024 planting initiative will be conducted in two stages: the first phase will involve the planting of 408 trees in the spring, followed by the second phase, which will see to the planting of an additional 2,500 trees during the autumn and winter months. Oradea stands out as the only municipality with a local register of green spaces featuring up-to-date data, last updated in spring 2022. The city boasts a green space area of 6,030,056 sq m (equivalent to 27.56 sq m per capita), housing nearly 100,000 trees and shrubs. Comparing park area to the total green space, most municipalities show park percentages exceeding 10% [68].

Micro-forests are gaining traction in cities globally, especially where space for greenery is limited. Their small size makes management easier. Architects now have the opportunity to prioritize biodiversity in their designs and material choices to ensure sustainable practices that do not deplete natural resources. Urban forest patches offer health benefits, superior cooling compared to ornamental plants, and pollutant removal. They also serve as buffers against disasters like storms and act as carbon sinks [153,154]. Oradea City Hall is spearheading an ecological revitalization project on a 6-hectare plot, transforming it into an urban forest complete with running and cycling tracks, sports fields, an observation tower, a pontoon for water sports, a natural-material amphitheater, and an adventure park [68].

6. Future Climate Projections

The global building industry significantly contributes to energy consumption, GHGs, and economic growth, yet it remains inadequately equipped to address the magnitude of transformation necessary for upcoming climate and societal challenges. Although technological innovations have progressed, energy consumption and emissions are persistently increasing, especially across emerging economies. Major driving forces encompass rising population numbers, urban expansion, climate variability, and widespread poverty. Efforts to decarbonize the sector are currently fragmented, slow, and insufficient, impeded by obsolete financial frameworks and ineffective policy enforcement. Achieving sustainable and fair development within the building industry demands comprehensive systemic reforms that combine technological advancements, economic restructuring, and cultural adaptation, all aligned with international climate objectives. Failure to act risks exacerbating social disparities and environmental degradation [155].

By 2025, the construction sector will have reached a turning point marked by an emphasis on innovation, safety, and sustainability. By prioritizing the use of low-carbon, ecologically friendly materials in conjunction with energy-efficient architectural solutions, the industry is actively tackling climate-related concerns. Modern technologies like artificial intelligence, automation, and digital platforms—including drone applications and Building Information Modeling—are improving safety procedures, making the best use of resources, and simplifying project execution, which reduces costs and increases efficiency. The European Union’s regulatory frameworks and international directives emphasize how urgent decarbonization and climate adaption are. Wearable technology and sophisticated predictive data analysis are supporting worker protection more and more. The sector is positioned for sustainable growth by incorporating these developments and encouraging interdisciplinary collaboration, producing infrastructure that is more resource-conscious and robust. The analysis emphasizes three closely linked approaches crucial for decreasing the carbon footprint of construction materials: advancing decarbonization techniques for traditional materials, reducing unnecessary extraction and manufacturing, and embracing regenerative materials [156].

Projections of future climate conditions indicate a substantial rise in global temperatures, which is expected to decrease heating demands while significantly amplifying cooling requirements, thereby increasing the likelihood of indoor overheating. This alteration in energy needs contributes to greater electricity use and escalates GHGs, particularly in regions where energy systems remain carbon-intensive. In countries with a predominantly renewable energy mix, such as Portugal, the environmental impact shifts from operational emissions to the embodied carbon in construction materials. The effectiveness of retrofit interventions, like external wall insulation, is highly dependent on regional climatic variables and future weather scenarios, with wall characteristics playing a pivotal role. Employing lifecycle assessment integrated with climate projections becomes essential for evaluating long-term building performance and securing thermal comfort with reduced ecological footprints [157].

An in-depth case analysis demonstrated that anticipated climate conditions spanning from 2020 to 2090 will have a profound impact on the long-term performance of buildings. Essential design features, including the thermal conductance of external walls and glazing (U-values), along with wall material density, were found to significantly shape outcomes related to lifecycle carbon emissions (LCCEs), lifecycle cost (LCC), and indoor thermal discomfort duration (IDH). By employing climate-projected datasets, a climate-resilient optimization framework was applied to an office structure located in a cold climate zone, resulting in notable improvements (i.e., IDH dropped by 4.3%, LCCE dropped by 44%, and LCC dropped by 8.2%). This integrative model utilizes advanced ensemble learning algorithms for precise forecasting, while optimization processes are guided by the constrained two-archive evolutionary algorithm. Furthermore, the selection of optimal resilient strategies is facilitated through the application of VIKOR, a robust multi-criteria assessment method [158].

A recent analysis demonstrated that anticipated climatic shifts will exert a considerable influence on energy requirements within buildings, particularly regarding cooling loads. Employing regionally downscaled climate projections from CORDEX, adjusted through bias-correction techniques, simulations conducted on social housing in Argentina indicated that higher emission trajectories amplify both energy use and uncertainty. In scenarios with moderate GHGs, cooling energy use varied between 27 and 37 MJ/m², while heating spanned from 303 to 330 MJ/m². Under more extreme emission forecasts, cooling needs escalated to 51–70 MJ/m², accompanied by a decline in heating demand to 266–326 MJ/m². Enhancing building energy performance not only reduced overall consumption but also narrowed the range of uncertainty. These findings underscore the inadequacy of single-model projections, affirming the necessity for ensemble-based modeling approaches to support resilient, climate-informed planning in construction practices [159].

AI offers powerful tools for interpreting extensive datasets related to climate patterns and infrastructure systems, thereby facilitating development strategies that are resilient to climate impacts. It contributes to the formulation of energy-optimized building and mobility solutions, enhances the integration of renewable sources into electrical grids, and supports efforts to curtail GHGs. By processing spatial information on land use and terrain, AI can pinpoint regions susceptible to flooding or erosion, informing anticipatory interventions such as constructing barriers or adjusting urban planning regulations. It also aids in implementing adaptive responses, including the reinforcement of existing structures, the introduction of nature-based solutions, or the strategic repositioning of critical infrastructure. Advanced AI simulations can forecast the potential consequences of rising seas and severe climatic events on built environments, equipping public institutions and communities with actionable insights [160].

Romania’s building industry must adapt to projected climate changes and leverage emerging technologies to remain resilient and sustainable. According to Romania’s Eighth National Communication on Climate Change projections based on CMIP6 data, average temperatures in Romania are expected to rise by 2–3 °C by 2050 under high-emission scenarios, with southern and eastern regions facing intensified heatwaves [161].

Cooling demand in Southern Europe is projected to increase significantly according to recent climate assessments. These shifts will likely decrease heating needs but drastically increase cooling requirements, especially during hotter summers [162,163].

In response, Romania’s Integrated National Energy and Climate Plan 2025–2030 projects that, by mid-century, renewable energy use will be more evenly balanced, with biomass, wind power, heat pumps, and hydrogen each projected to supply roughly 16% to 19% of the total final energy consumption from renewables [164]. This aligns with broader EU strategies like “Fit-for-55”, which aim to fully decarbonize heating and cooling by mid-century [165].

To meet these demands, future Romanian buildings must incorporate a combination of climate-adaptive strategies that enhance energy performance and resilience. First, passive cooling techniques—such as natural ventilation, external shading elements, high-performance insulating windows, and vegetated (green) roofs—should be widely implemented to reduce peak cooling loads during increasingly hot summers. Second, heating, ventilation, and air conditioning systems should be integrated with advanced technologies, including electric heat pumps, thermal energy storage solutions, and smart control systems powered by artificial intelligence, in order to optimize energy consumption and improve buildings’ responsiveness to environmental conditions. Lastly, building envelope design must be guided by comprehensive lifecycle assessments and future climate projection data, ensuring the selection of materials and construction methods that maximize long-term thermal efficiency and minimize environmental impacts.

The convergence of climate projections and policy targets necessitates a shift in Romania’s construction paradigm, from traditional, heating-focused designs to integrated, adaptive architectures that combine passive strategies, advanced systems, and data-driven optimization for a truly climate-resilient built environment.

7. Conclusions

Climate change drives measurable shifts in climate patterns, with the construction sector being a key contributor, necessitating urgent adaptation through strategic planning, design, material selection, and architecture. Romania shows growing commitment to climate-adaptive construction and sustainable urban development by integrating passive design, renewable energy, smart materials (e.g., electrochromic glazing, hemp insulation), and circular economy principles, despite economic and regulatory barriers. Urban projects in Oradea, Brașov, Bucharest, and other cities illustrate the integration of environmental responsibility and resilience, reflecting Romania’s growing commitment to sustainable urban development and climate-responsive architecture across the country.

To accelerate the transition to climate-resilient construction, clear policy actions are essential. Romania must update and harmonize building codes to mandate passive, adaptive, and renewable energy solutions, ensuring new constructions meet robust resilience standards. Simplifying permitting and offering targeted financial incentives is critical to fostering innovation and encouraging the adoption of advanced technologies such as prefabrication and sustainable materials. Additionally, investing in specialized training and capacity building will close expertise gaps, empowering architects, engineers, and builders to implement cutting-edge solutions effectively. The enhanced use of localized climate data should support evidence-based policymaking and urban planning, enabling tailored responses to regional climate vulnerabilities.

These strategic recommendations, grounded in Romania’s experience, provide practical guidance for Romania and other emerging economies facing similar challenges. Romania’s successes in funding schemes and regulatory support exemplify how aligned public policy and private innovation can drive systemic change in the construction sector. This integrated approach is vital for building sustainable cities that ensure environmental sustainability, economic feasibility, and social well-being in a warming world.