Search Results (533)

Hakka traditional vernacular dwellings embody regionally specific climatic adaptation strategies. This study takes the Meizhou Guangludi enclosed house as a case study to evaluate its climate adaptability with longevity and passive survivability factors of the Hakka three-hall enclosed house under subtropical climatic conditions. A mixed research method is employed, integrating visualized parametric modeling analysis and on-site measurement comparisons to quantify wind, temperature, solar radiation/illuminance, and humidity, along with human comfort zone limits and building environment. The results reveal that nature erosion in the Guangludi enclosed house is the most pronounced during winter and spring, particularly on exterior walls below 2.8 m. Key issues include bulging, spalling, molding, and fractured purlins caused by wind-driven rain, exacerbated by low wind speeds and limited solar exposure, especially at test spots like the E8–E10 and N1–N16 southeast and southern walls below 1.5 m. Fungal growth and plant intrusion are severe where surrounding trees and fengshui forests restrict wind flow and lighting. In terms of passive survivability, the Guangludi enclosed house has strong thermal insulation and buffering, aided by the Huatai mound; however, humidity and day illuminance deficiencies persist in the interstitial spaces between lateral rooms and the central hall. To address these issues, this study proposes strategies such as adding ventilation shafts and flexible partitions, optimizing patio dimensions and window-to-wall ratios, retaining the spatial layout and Fengshui pond to enhance wind airflow, and reinforcing the identified easily eroded spots with waterproofing, antimicrobial coatings, and extended eaves. Through parametric simulation and empirical validation, this study presents a climate-responsive retrofit framework that supports the sustainability and conservation of the subtropical Hakka enclosed house. Full article

Building energy consumption occupies an increasing proportion of the total energy consumption of society, and the use of energy-efficient windows can have great significance for energy saving. This case study examined the energy efficiency of various types of windows of the buildings on the University of New Brunswick campus, Fredericton, Canada. The energy performance of these windows was monitored by an infrared thermal camera from November 2021 to April 2022 and assessed in terms of the heat loss between different types of windows. The main findings were that (1) the temperature distribution of a window was strongly influenced by the indoor and outdoor temperature; (2) wood frame windows showed better insulation properties than metal frame ones; (3) fixed windows had a better energy performance than sliding windows and single-hung windows; and (4) the east orientation of a building and the use of Low-E glazing were the most effective expedients to reduce the winter energy required. By comparing these findings with earlier research, this study contributes new insights for cold climates, underscoreing the importance of Low-E glazing and configuration choice in building retrofits for energy-efficient, sustainable construction. Full article

Underground high-voltage transmission cables, especially high-pressure fluid-filled (HPFF) pipe-type cable systems, are critical components of urban power networks. These systems consist of insulated conductor cables housed within steel pipes filled with pressurized fluids that provide essential insulation and cooling. Despite their reliability, HPFF cables experience faults caused by insulation degradation, thermal expansion, and environmental stressors, which, due to their subtle and gradual nature, complicate incipient fault detection and subsequent fault localization. This study presents a novel, proactive, and retrofit-friendly predictive condition monitoring method. It leverages distributed accelerometer sensors non-intrusively mounted on the HPFF steel pipe within existing manholes to continuously monitor vibration signals in real time. A physics-enhanced convolutional neural network–long short-term memory (CNN–LSTM) deep learning architecture analyzes these signals to detect incipient faults before they evolve into critical failures. The CNN–LSTM model captures temporal dependencies in acoustic data streams, applying time-series analysis techniques tailored for the predictive condition monitoring of HPFF cables. Experimental validation uses vibration data from a scaled-down HPFF laboratory test setup, comparing normal operation to incipient fault events. The model reliably identifies subtle changes in sequential acoustic patterns indicative of incipient faults. Laboratory experimental results demonstrate a high accuracy of the physics-enhanced CNN–LSTM architecture for incipient fault detection with effective data feature extraction. This approach aims to support enhanced operational resilience and faster response times without intrusive infrastructure modifications, facilitating early intervention to mitigate service disruptions. Full article

The growing interest in smart buildings and the integration of IoT-based technologies is driving the development of new tools for monitoring and optimizing indoor environmental quality (IEQ). However, many existing solutions remain expensive, invasive and inflexible. This paper presents the design and validation of a compact, low-cost, and real-time sensor system, conceived for seamless integration into indoor environments. The system measures key parameters—including air temperature, relative humidity, illuminance, air quality, and sound pressure level—and is embeddable in standard office equipment with minimal impact. Leveraging 3D printing and open-source hardware/software, the proposed solution offers high affordability (approx. EUR 33), scalability, and potential for workspace retrofits. To assess the system’s performance and relevance, dynamic simulations were conducted to evaluate metrics such as the Mean Radiant Temperature (MRT) and illuminance in an open office layout. In addition, field tests with a functional prototype enabled model validation through on-site measured data. The results highlighted significant local discrepancies—up to 6.9 °C in MRT and 28 klx in illuminance—compared to average conditions, with direct implications for thermal and visual comfort. These findings demonstrate the system’s capacity to support high-resolution environmental monitoring within IoT-enabled buildings, offering a practical path toward the data-driven optimization of occupant comfort and energy efficiency. Full article

Climate change is intensifying the frequency and severity of extreme weather events, threatening the resilience of buildings and urban infrastructure. While technical solutions for climate adaptation in buildings are well documented, their economic viability remains a critical, yet underexplored, dimension of decision-making. This novel systematic review analyzes publications with an exclusive focus on climate adaptation strategies for buildings using cost-based evaluation methods. This review categorises the literature into three methodological clusters: Cost–Benefit Analysis (CBA), Life Cycle Costing (LCC), and alternative methods including artificial intelligence, simulation, and multi-criteria approaches. CBA emerges as the most frequently used and versatile tool, often applied to evaluate micro-scale flood protection and nature-based solutions. LCC is valuable for assessing long-term investment efficiency, particularly in retrofit strategies targeting energy and thermal performance. Advanced methods, such as genetic algorithms and AI-driven models, are gaining traction but face challenges in data availability and transparency. Most studies focus on residential buildings and flood-related hazards, with a growing interest in heatwaves, wildfires, and compound risk scenarios. Despite methodological advancements, challenges persist—including uncertainties in climate projections, valuation of non-market benefits, and limited cost data. This review highlights the need for integrated frameworks that combine economic, environmental, and social metrics, and emphasises the importance of stakeholder-inclusive, context-sensitive decision-making. Ultimately, aligning building adaptation with financial feasibility and long-term sustainability is achievable through improved data quality, flexible methodologies, and supportive policy instruments. Full article

The integration of Mechanical Ventilation with Heat Recovery (MVHR) systems into heritage buildings poses a series of challenges, largely attributable to architectural constraints and conservation requirements. The present study offers an operational campaign of an MVHR system installed during the energy retrofit of a protected residential heritage dwelling in Vitoria-Gasteiz, Spain. Although environmental monitoring was carried out throughout the year, representative spring, autumn and winter days of continuous operation were analysed, as the occupants frequently avoided using the system due to noise perception. This limitation highlights the importance of considering acoustic comfort and user acceptance as critical factors in the long-term viability of MVHR in heritage contexts. The system was assessed under real-life conditions using continuous environmental monitoring, with a focus on indoor air quality (IAQ), thermal efficiency, airflow balance, and pressure losses. Despite the acceptable mean apparent thermal effectiveness (0.74) and total useful efficiency (0.96), the system’s performance was found to be constrained by significant flow imbalance (up to 106%) and elevated pressure drops, which were attributed to the legacy of the duct geometry. The results obtained demonstrate IAQ improved overall, with mean CO₂ concentrations below ~650 ppm across the analysed dataset; however, daily means occasionally exceeded 900–1000 ppm during high-occupancy periods and in the absence of spatially distributed demand control. These exceedances are consistent with the measured outdoor baseline (~400–450 ppm) and reflect the need for post-commissioning balancing and room-level sensing to sustain Category II performance in heritage dwellings. This study provides empirical evidence on the limitations and opportunities of MVHR deployment in historic retrofits, thus informing future guidelines for sustainable interventions in heritage contexts. Full article

With government, industry, and public pressure to decarbonize the building sector through reducing embodied and operational emissions, there have been a wide range of innovative materials used in building envelope retrofits. Although these innovative materials, such as super insulating materials, bio-based insulation, and many others, are assessed on thermal performance and code requirements before use in retrofits, there is no unified standard assessment metric for hygrothermal performance of innovative materials in building envelope retrofits. This paper performs a rapid review of the available literature from January 2013 to March 2025 on hygrothermal performance assessment metrics used in retrofits. Using rapid review methods to search for records in Scopus, Web of Science, and Google Scholar, fifty-nine publications were selected for bibliometric and qualitative analysis. Most selected publications include discussions and analysis of relative humidity in the wall assembly post retrofit, moisture content, and mould index within the envelope. There is a research gap in publications considering hygrothermal damage functions such as freeze–thaw index, relative humidity and temperature (RHT) index, or condensation prediction. There is also a research gap in country and climate studies and analyses of in situ retrofits with innovative materials, and occupant comfort post retrofit. Full article

External Thermal Insulation Composite Systems (ETICSs) are increasingly applied in both new construction and energy retrofitting, where long-term durability under environmental exposure is critical to preserving thermal efficiency. Moisture ingress represents a key degradation factor, reducing insulation performance and undermining energy savings promoted by the ETICS. The effectiveness of these systems is strongly influenced by surface protection, which also reflects aesthetic and biological resistance. This study investigates the influence of three commercial protective surface coatings, characterized by hydrophobicity, photocatalytic activity, and resistance to biological growth, on ETICS finishes based on acrylic, natural hydraulic lime (NHL), and silicate binders. An artificial aging protocol was employed to evaluate coating stability and compatibility with the finishing layers. Results show that acrylic-based finishes provided superior durability and protection, while coatings on NHL and silicate substrates exhibited lower performance. Notably, a TiO₂ enriched photocatalytic coating, despite improved self-cleaning potential, demonstrated the least durability. The findings highlight that optimal ETICS protection requires coatings that combine low water absorption, effective drying, and biological resistance, thereby ensuring sustained thermal and energy performance over time. Full article

Summer overheating has emerged as the primary comfort challenge in rural housing under a warming climate. Conventional retrofit measures are often infeasible due to high costs and limited technical capacity. This study investigates how spatial configuration influences summer thermal conditions while keeping envelope materials constant, focusing on rural dwellings in the Guanzhong region of China. Three representative prototypes are analyzed: the traditional courtyard type, the deep continuation type, and the progressive combined type. Thermal performance is evaluated using the Predicted Mean Vote (PMV) index through Ladybug and Honeybee simulations based on long-term meteorological data, and validated with multi-room field measurements. Two parametric analyses further test the effects of window opening rates (0.2–0.5) and room width-to-depth ratios (1:1–1:2.5). Results indicate that courtyards and galleries function as transitional zones, creating discrete yet connected thermal units and reducing PMV near edges. Second-floor rooms show a ventilation advantage with an average PMV reduction of 0.08. Enlarging window openings improves PMV only when cross-ventilation paths exist, while ratios wider than 1:2 raise PMV and slightly influence adjacent rooms. Field measurements confirm these simulated patterns. Cross-regional comparisons with Argentina, Brazil, and Japan further demonstrate that once the envelope is adequate, the spatial organization becomes the key driver of summer comfort. The study highlights practical, low-cost strategies such as reallocating high-use rooms to favorable zones, adding targeted shading, and ventilation, and introducing lightweight spatial interventions. These measures enhance summer comfort without invasive construction. Full article

Reflective materials, characterized by high albedo and thermal emissivity, offer effective passive cooling strategies for reducing building energy demand. While prior studies have developed thermal transfer models validated under laboratory conditions or conducted short-term monitoring in non-air-conditioned spaces, their effectiveness in operational buildings remains underexplored. This research evaluates the change in cooling energy demand and indoor thermal comfort in a retrofitted office building with reflective materials in China’s Hot Summer and Cold Winter (HSCW) zone. The calibrated WUFI^®Plus simulations show that the application of reflective roof and window materials can result in an 11.3% reduction in cooling energy demand. Moreover, occupant surveys indicate improved thermal perception, with the mean Thermal Comfort Vote (TCV) rising from −0.75 to −0.30, thermal acceptability increasing from 0.10 to 0.35, and 80% of occupants reporting cooler conditions. These subjective results align with simulated Predicted Mean Vote (PMV) reductions (0.82 → 0.74), confirming the retrofit’s effectiveness. While the energy savings are more modest than those reported in Mediterranean climates, they are generally consistent with the energy saving ratios of buildings in the HSCW region as evaluated by previous studies. This study provides a framework for assessing retrofits in occupied buildings with reflective materials and indicates the practicality of such retrofits as an economic, low-disruption strategy for upgrading aging office building stocks in the HSCW zone. Full article

Rural residential structures account for a substantial share of carbon emissions within the construction industry. Enhancing building envelopes can diminish structural carbon emissions, thereby facilitating the attainment of “dual carbon” objectives. Current algorithm-driven research on the low-carbon retrofitting of residential building envelopes generally neglects temperate regions in low-latitude plateaus, often misses embodied carbon, and utilizes rather limited methodologies for issue identification. This study focuses on rural dwellings in Lijiang, utilizing a cross-validation method that incorporates sensitivity analysis, infrared thermal imaging, and energy efficiency criteria to systematically identify vulnerable regions in the building envelope. Consequently, critical issues are converted into optimization variables for the NSGA-II method, aiming to minimize both embodied carbon and operational energy usage. BAPV is concurrently implemented to partially mitigate renovation expenses. A weighted summation approach delineates stakeholder preferences, resulting in three optimum options. The findings reveal that all three methods correspond to their unique preferences, illustrating distinct trade-offs among energy efficiency, carbon reduction, and economic feasibility. The government-oriented approach attained an energy saving rate (ESR) of 45.11%, a life cycle carbon reduction (LCCR) of 1215.76 kgCO₂/m², and a dynamic payback period (DPP) of 3.65 years. The architect-oriented approach realized the highest energy savings and carbon reduction (45.41%, 1218.96 kgCO₂/m²), with a payback period of 3.99 years. The villager-oriented approach emphasized economic viability, achieving an energy savings rate of 41.55%, a carbon reduction of 1149.46 kgCO₂/m², and the shortest payback period of 2.87 years. This study provides an optimization process and reference parameters for building envelopes in a low-carbon design for residential buildings in temperate regions of low-latitude plateaus. Full article

Fossil fuel-based power production faces challenges, particularly greenhouse gas emissions, that contribute to global warming. This paper explores retrofitting an existing 207.8 MW coal-fired steam power unit with a Concentrated Solar Power (CSP) tower system and Thermal Energy Storage (TES) systems to create a hybrid solar–coal power plant. The concept integrates a solar component and a two-tank TES system into the existing steam Rankine cycle. Thermodynamic modeling and balance calculations were performed using Ebsilon Professional software (version 16) to analyze the design. Three injection points for feedwater preheating were analyzed, with flow rates that varied from 10 to 100 kg/s. Thermodynamic simulations show that solar contributions of 16.0 MW (Variant 1), 27.6 MW (Variant 2), and 37.6 MW (Variant 3) increase net electricity output to 213.5 MW, 216.8 MW, and 219.3 MW, respectively. The corresponding thermal efficiencies rise from 42.6% to 43.8%, while the hybrid system’s total efficiency improves up to 29.6%. These results demonstrate that controlled feedwater diversion and solar integration can enhance performance, reduce coal dependency, and lower CO₂ emissions without compromising operational stability. Full article

There is an urgent need to implement sustainable solutions in the construction sector, particularly within the Peruvian context, where regulations on energy efficiency and building rehabilitation are still under development. This study addresses the energy and social rehabilitation of the Mercado Central in Lima, with the aim of identifying the most effective interventions from both energy and economic perspectives while promoting urban sustainability. A detailed assessment of the building’s original state—covering the thermal envelope and technical systems—was conducted, followed by fifty energy simulations using Ce3X© v.2.3. software. Based on the obtained energy rating, several envelopes and system improvements were proposed and evaluated in terms of energy savings, cost-effectiveness, and social benefits. The most advantageous option, Measure M9, combines interventions in roofs, openings, and installations. It achieved a global energy rating of 17.6 A, with a projected lifespan of 75 years and an investment of EUR 1,642,457.01, recoverable in just 1.4 years. The results highlight the potential of integrated retrofitting strategies to simultaneously improve energy performance and social impact. Measure M9 emerges as the most viable solution, providing a replicable model for sustainable urban rehabilitation in Peru and other regions facing similar challenges. Full article

This study evaluates the passive thermal resilience of two full-scale residential buildings during natural summer heatwaves and blackout-like conditions in a temperate European climate. The buildings share identical geometry and ventilation but differ in envelope mass and ground coupling. Building B1 is a masonry structure with a slab-on-ground floor, while B2 is a lightweight timber-frame house. In 2019, B1 underwent a retrofit in which floor insulation was removed to enable direct subsoil heat exchange. Three complementary frameworks were applied: model IOD, AWD, OEF, the indicators AF and αIOD, and the health-based scenario rating HE, HIHH, and WBGT. Across all metrics, B1 demonstrated superior resilience, with overheating fully eliminated after ground coupling was introduced. B2, in contrast, remained vulnerable under both moderate and extreme events. The findings highlight the critical role of thermal mass and soil buffering in maintaining safe indoor conditions without active systems. Under certain circumstances, omitting under-slab insulation can improve summer resilience without significantly compromising winter performance. A companion life-cycle analysis confirms lower cumulative carbon emissions for B1 under all SSP scenarios to 2100. Passive ground coupling thus emerges as a low-cost, maintenance-free adaptation strategy with co-benefits for mitigation and occupant safety. Full article

This study presents a detailed analysis of the energy performance and thermal comfort conditions in four existing school buildings located in Madrid, Spain. Dynamic simulations were conducted using TeKton3D—(iMventa Ingenieros, Málaga, Spain)- an open-source tool based on the EnergyPlus engine—to model four improvement scenarios: (I) current state, (II) envelope retrofitting with ETICS and high-performance glazing, (III) solar control strategies, and (IV) incorporation of mechanical ventilation with heat recovery. Each building was simulated under both current and projected 2050 climate conditions. The case studies were selected to represent different construction periods and urban contexts, including varying levels of exposure to the urban heat island effect. This approach allows the results to reflect the diversity of the existing school building stock and its different vulnerabilities to climate change. The results show that envelope retrofitting substantially reduces heating demand but may increase cooling needs, particularly under warmer future conditions. Solar control strategies effectively mitigate overheating, while mechanical ventilation with heat recovery contributes to improved comfort and overall efficiency. This study highlights the trade-offs between energy savings and indoor environmental quality, underlining the importance of integrated renovation measures. The study provides relevant data for decision-making in climate-resilient building renovation, aligned with EU goals for nearly zero and zero-emission buildings. Full article