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We analyze the shear response of grafted polymer chains in shear flow via coarse-grained molecular dynamics simulations with an explicit solvent. We find that the solvent flow penetrates into almost the whole brush for "mushroom"-type brushes but only a few bond distances for dense brushes. In all cases, the external stress on the wall equals the entropic stress associated with the distorted polymer conformations. We find that the external stress increases linearly with shear rate at low rates and sublinearly at high rates. The transition from linear to sublinear scaling occurs where chains react to flow by reorienting. Sublinear scaling with shear rate disappears if the shear rate is nondimensionalized with the effective relaxation time of chain subsegments located in the outer part of the brush that experiences flow. [ABSTRACT FROM AUTHOR]

Cracks represent one of the most common types of damage in building structures and it is crucial to detect cracks in a timely manner to maintain the safety of the buildings. In general, tiny cracks require focusing on local detail information while complex long cracks and cracks similar to the background require more global features for detection. Therefore, it is necessary for crack detection to effectively integrate local and global information. Focusing on this, a local–global feature adaptive fusion network (LGFAF-Net) is proposed. Specifically, we introduce the VMamba encoder as the global feature extraction branch to capture global long-range dependencies. To enhance the ability of the network to acquire detailed information, the residual network is added as another local feature extraction branch, forming a dual-encoding network to enhance the performance of crack detection. In addition, a multi-feature adaptive fusion (MFAF) module is proposed to integrate local and global features from different branches and facilitate representative feature learning. Furthermore, we propose a building exterior wall crack dataset (BEWC) captured by unmanned aerial vehicles (UAVs) to evaluate the performance of the proposed method used to identify wall cracks. Other widely used public crack datasets are also utilized to verify the generalization of the method. Extensive experiments performed on three crack datasets demonstrate the effectiveness and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Saudi Arabia faces significant challenges in managing the rising energy consumption in buildings driven largely by its hot climatic conditions. As a result, retrofitting building facades to enhance energy efficiency has become a critical strategy. This study assesses the effectiveness of various façade retrofit strategies in reducing cooling electricity consumption using a real-time case study in Dhahran, Saudi Arabia. The strategies explored include external wall upgrades, window replacements, and installation of shading devices. Each strategy was evaluated individually, considering the reduction in heat gains, cooling load, and payback period as key performance indicators. To further maximize energy efficiency, these strategies were also analyzed in combination using the genetic algorithm optimization method, yielding 224 possible facade configurations. The optimal solution included the use of an External Thermal Insulation Composite System (ETCIS) in walls, louvers in windows, and low-emissivity coating with Argon gas-filled glazing, achieving a cooling energy reduction of approximately 16% and a payback period of 14.8 years. This study provides several recommendations for improving the efficiency of retrofitting building façades in hot climatic conditions. [ABSTRACT FROM AUTHOR]

Buildings consume 30% to 40% of all primary energy worldwide and are responsible for 50% of total greenhouse gas emissions. Canada has set a target of reducing greenhouse gas emissions by at least 80% by 2050. The aim of this paper is to investigate thermal bridging in four high-efficient buildings, such as those built to LEED standards. Thermal bridging is a major source of heat loss in many buildings, manifesting itself through exterior envelopes, particularly through studs and wall systems. LEED is an evaluation system that rates how sensitive buildings are to the environment, with one of its main objectives being the reduction of greenhouse gases (GHG) emissions through the implementation of highly efficient mechanical systems and the design of durable and efficient exterior wall systems with appropriate insulation. This research investigates and identifies the location of thermal bridging in high-efficiency buildings using non-destructive testing methods such as thermal imaging and THERM simulations. The study involves using infrared thermography to inspect surface temperature variations and detect irregular thermal patterns that correspond to thermal bridging. By collecting record drawings to identify the construction systems used in the external wall compounds, capturing thermal images with high-resolution infrared cameras, and comparing these images with simulation results, the research provides a comprehensive analysis of thermal performance. The findings from this research are significant, particularly in the context of window curtain walls, steel studs, brick shelf angles, timber frames, and roof hatches—all of which were identified as critical areas of concern due to their propensity to thermal bridges. For instance, window curtain walls, with their metal frames and large glass surfaces, showed temperature drops of up to 8°C. Steel studs, which are highly conductive of heat, resulted in temperature drops of up to 5°C, while brick shelf angles showed a temperature drop of 4°C due to heat conduction through the metal. In timber frame structure the building envelope connector showed temperature drops of up to 7°C. Additionally, roof hatches, necessary for rooftop access, were found to cause the most significant temperature drop of 10°C. The findings highlight the significant impact of thermal bridges on overall energy efficiency, emphasizing the need for careful design and construction practices to minimize heat losses. Addressing these thermal bridging issues is crucial for achieving the ambitious GHG reduction targets and enhancing the sustainability of high-performance buildings. [ABSTRACT FROM AUTHOR]

The study investigates the impact of improved synthetic amorphous silica, specifically developed aerogel-based insulating coatings, Quartzene (Qz), on energy efficiency in buildings across cold and warm climate zones. Simulations were conducted on various coatings and thicknesses for exterior and interior wall surfaces, as well as roofs. These were evaluated using a prototype residential building under dynamic thermal conditions. Wall coatings were analyzed, including a base plaster and a mixture with 10%Wt aerogel-based Quartzene. Additionally, three roof coating samples were tested: Qz 12.5%Wt, TiO2 3.3%Wt, and a blend of aerogel-based mixtures and TiO2. Mixtures containing Qz exhibited the lowest thermal conductivity (0.05 W/(m·K)) and high short-wave reflectance (up to 0.93 μm), impacting transmission loads, time lag, and decrement factor. Energy savings of up to 11% were observed in warm climates when implementing the coatings (unaged performance). Overall, the coated surfaces increased time lag and reduced decrement factor compared to uncoated surfaces. Aerogel-based coatings showed enhanced effectiveness in lowering transmission loads. [ABSTRACT FROM AUTHOR]

In this study, we investigated inspection robots that can safely, accurately, and quickly perform hammer sound inspections on tile exterior walls and present new wall hammering inspection systems using two-wheeled multi-copters. Our results yielded the following five advantages. First, the proposed multi-copter can use its wheels not only to move freely on the walls of buildings but also to overcome obstacles on the walls. Therefore, almost any tile wall surface can be inspected for hammering sound. Second, the multi-copter was equipped with both hammer-shaped rods to hit the tile exterior wall and microphones to collect the hammer sound of the tile, while moving quickly on the wall surface. Third, the wall hammering inspection systems can be used safely with a work assistance mechanism using a wire even in densely populated areas, such as urban areas, because the multi-copter has high wind resistance against crosswinds by both pushing against the wall and operating by the wire. Fourth, we presented some automatic control systems that make the multi-copter operation easy during hammering inspections and demonstrated its usefulness through experiments. Fifth, we proposed useful methods for detecting floating tiles based on the hammering results, conducted some outdoor flight experiments on building exterior walls, and demonstrated that floating tiles can be determined with high accuracy. [ABSTRACT FROM AUTHOR]

The European Community has prioritized reducing energy consumption and improving energy efficiency in the building sector, along with ensuring increasingly high standards of thermal comfort, as key goals over recent decades. Given the impact of climate change, the rising frequency of extreme weather events, and the rapid shifts in peak demand during both winter and summer, buildings must efficiently respond to sudden and extreme temperature fluctuations while maintaining optimal indoor comfort. Phase-change materials (PCMs), which can adapt their thermophysical properties in response to external conditions, may offer a solution for enhancing building resilience to climate change. This paper evaluates the benefits of integrating various PCMs with plasterboard in the energy retrofit of a multi-family complex in a Mediterranean climate. The study examines the application of a PCM with a melting temperature of 25 °C at three different thicknesses (74.2 mm, 37.1 mm, and 20.8 mm) to external walls, ceilings, and both walls and ceilings simultaneously. Among the various applications, using the PCM on walls alone maximized heating savings as thickness increased (26.6%), while ceiling application maximized cooling energy savings (17.5%). Combined solutions offered the most balanced seasonal benefits, leading to the greatest overall energy reductions (24.1%). [ABSTRACT FROM AUTHOR]

This article emphasizes the significance of understanding the actual thermal properties of thermal insulation materials, which are crucial for avoiding errors in building design and estimating heat losses within the energy balance. The aim of this study was to analyse the thermal parameters of selected thermal insulation materials, particularly in the context of their stability after a period of storage under specific conditions. The materials chosen for this study include commonly used construction insulations such as polystyrene and mineral wool, as well as modern options like rigid foam composites. Experimental studies were conducted, including the determination of the thermal conductivity coefficient λ, as well as numerical analyses and analytical calculations of heat flow through a double-layer external wall with a window. The numerical analyses were performed using the TRISCO software version 12.0w, based on the finite element method (FEM). A macrostructural analysis of the investigated materials was also performed. The findings indicated that improper storage conditions adversely affect the thermal properties of insulation materials. Specifically, storing materials outdoors led to a deterioration in insulating properties, with an average reduction of about 4% for the standard materials and as much as 19% for the tested composite material. Insufficient understanding of the true thermal properties of insulation materials can result in incorrect insulation layer thickness, degrading the fundamental thermal parameters of external walls. This, in turn, increases heat loss through major building surfaces, raises heating costs, and indirectly contributes to greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Use of 100 % recycled aggregates in concrete – report on practical applications This article reports on eight practical examples of applications for concrete with 100 % recycled aggregates. The applications include reinforced/unreinforced bored piles, foundations, load‐bearing internal/external walls, columns and floor slabs as well as balcony elements. Some components were realised as architectural concrete components. The respective project is summarised together with the results of the concrete development and concrete testing as well as the experience gained from obtaining special approvals in individual cases. Based on the findings from the various practical projects, it can be concluded that concrete with 100 % RC‐GK can be used for a large number of applications, so far limited to up to XC4 and XF3. Compressive strength for ready‐mix concrete up to C35/45 with good workability even with pumped concrete (here: pumping distance 45 m) using 100 % RC‐GK type 1 were possible without any problems. A concrete with sufficient early strength and a final strength of C40/50 was developed for precast elements. In two examples, RC‐GK type 2 was used for the coarse grain fraction and RC‐GK type 1 for the sand. All the projects presented have already been completed or are nearing completion. The feasibility of 100 % RC concrete in practice has thus been successfully demonstrated in several cases. [ABSTRACT FROM AUTHOR]

Achieving year‐round energy savings in buildings holds great significance toward reaching carbon neutrality and sustainability. Switchable thermal‐management materials offer an energy‐free solution to dynamically regulating internal building temperatures, by passively emitting heat into cold outer space in summer, and absorbing heat from hot sunlight in winter. In addition to dynamic thermal regulation, color display is another pursuit for addressing aesthetic considerations; however, most current dynamically switchable materials lack color options, due to an optical conflict between adaptive solar reflection and selective visible absorption, limiting their wide adoption in aesthetic scenarios such as commercial exterior walls. Herein, a colored temperature‐adaptive cloak (CTAC) that achieves dynamically switchable thermal management in an energy‐neutral way without sacrificing year‐round vibrant color display is reported. This is realized by decoupling solar reflectivity modulation and color display through the choice of two individual constituent components, including thermochromic microcapsules, and fluorescent dyes. Moreover, compared to single‐mode samples with similar colors, the CTAC with dual modes stays 5.6–3.4 °C warmer during cold winter and 14.9–7.9 °C cooler during hot summer (peak solar irradiance: ≈735 and 1030 W m−2, respectively), exhibiting a remarkable potential to achieve year‐round building energy savings. [ABSTRACT FROM AUTHOR]

The layout of the exterior retaining walls and external thermal insulation demands often introduce an eccentricity between the central axes of the beams and columns, leading to what is termed as an eccentric beam-column joint. Such the beam eccentricity is a key factor in shear failures within the joint region. This study addresses the negative impact of beam eccentricity on the shear capacity of reinforced concrete (RC) eccentric beam-column joints. Current research indicates that in the five prevailing shear capacity formulas of RC eccentric joints, adverse effects are primarily accommodated by either reducing the joint's effective width (b j) or implementing an eccentricity influence factor. The study challenges the validity of these approaches by dissecting the impact of singular and interactive factors, including. Eccentricity (2 e / b c), beam-to-column width ratio (b b/ b c), and the column's aspect ratio (h c/ b c). It was observed that while the influence of 2 e / b c is generally well-accounted for, the effects of b b/ b c and h c/ b c are not adequately considered in the Chinese code and ACI-318. Leveraging the softened strut-and-tie model and insights from these examinations, a refined formula for determining the shear capacity of eccentric joints is introduced. This formula incorporates the detrimental effects of beam eccentricity through a newly conceptualized eccentric influence factor, which is a function of both 2 e / b c and b b/ b c. Compared to existing models, this proposed formula also factors in the beam-to-column depth ratio and the longitudinal reinforcement in the middle of column section. Validation against experimental data from 26 eccentric joints demonstrates that the proposed formula yields predictions with the closest proximity to actual test results and the least variability compared to the five established formulas. This approach to considering the effects of e / b c and b b/ b c proves to be slightly more accurate than Zhou's model, making it a promising alternative for practical applications. [ABSTRACT FROM AUTHOR]

The application of phase change materials (PCMs) in prefabricated buildings plays an important role in green building energy savings. In this paper, the wall with a phase change interlayer is composed of common building materials, and a phase change interlayer is filled with paraffin and nylon solid skeletons printed using 3D technology. The ordinary wall as the reference object is made of only common building materials, and its dimensions are the same as those of the composite wall with PCM interlayer. A comparison of unsteady heat transfer characteristics between ordinary wall and wall with a phase change interlayer is studied experimentally by infrared image and accurate temperature measurement. The experimental results show that the thickness, position of the phase change interlayer, and heating temperature have an important impact on the thermal insulating performance of the wall. According to the experimental data, when the interlayer thickness is 3 cm and located on the inner side of the wall with a heating temperature of 55°C, the wall not only has the desired insulation performance but also has a high utilization rate of phase change materials. The research results provide a basis for further improvement of the wall by proposing a new application of phase change materials in prefabricated buildings. [ABSTRACT FROM AUTHOR]

Wind-driven rain (WDR) constitutes a significant source of moisture for building facades, which poses considerable challenges to both the thermal insulation performance and long-term durability of walls. Prior studies have contributed significantly to the understanding of fluid behavior and moisture response of WDR upon impacting walls. However, the quantification of absorbed rainwater by the wall remains elusive. To address this gap, this study focuses on comprehending the dynamic WDR absorption behavior of various exterior finishing materials. Specifically, nine types of finishing materials were selected as research objects and conducted field measurements. The findings reveal that WDR absorption ratio is influenced by physical parameters of materials, surface waterproofing and the cumulative WDR. Leveraging multiple regression fittings, we established an empirical WDR absorption ratio calculation mode. This model serves as a valuable reference for determining building simulation parameters regarding dynamic moisture boundary conditions on the exterior surfaces of walls. By providing empirical insights into WDR absorption, our research contributes to a more comprehensive understanding of moisture behavior in building envelopes, thereby aiding in the development of effective strategies for enhancing building performance and durability. [ABSTRACT FROM AUTHOR]

Three-dimensional printing technology continues to evolve, enabling new applications in manufacturing. Extensive research in the field of biomimetics underscores the significant impact of the internal geometry of building envelopes on their thermal performance. Although 3D printing holds great promise for improving thermal efficiency in construction, its full potential has yet to be realized, and the thermal performance of printed building components remains unexplored. The aim of this paper is to experimentally examine the thermal insulation characteristics of prototype cellular materials created using 3D additive manufacturing technologies (SLS and DLP). This study concentrates on exploring advanced thermal insulation solutions that could enhance the energy efficiency of buildings, cooling systems, appliances, or equipment. To this end, virtual models of sandwich composites with an open-cell foam core modeled after a Kelvin cell were created. They were characterized by a constant porosity of 0.95 and a pore diameter of the inner core of the composites of 6 mm. The independent variables included the different material from which the composites were made, the non-uniform number of layers in the composite (one, two, three, and five layers) and the total thickness of the composite (20, 40, 60, 80, and 100 mm). The impact of three independent parameters defining the prototype composite on its thermal insulation properties was assessed, including the heat flux (q) and the heat transfer coefficient (U). According to the experimental tests, a five-layer composite with a thickness of 100 mm made of soybean oil-based resin obtained the lowest coefficient with a value of U = 0.147 W/m2·K. [ABSTRACT FROM AUTHOR]

Significant emphasis has been directed towards the advancement of antimicrobial agents with the objective of mitigating and managing the transmission of infectious diseases. Silver nanoparticle-decorated carbon nanotube (Ag@CNT)-based metal organic frameworks (MOFs) represent a promising nanomaterial endowed with significant antibacterial efficacy and hold potential for diverse medical applications, especially mitigating the proliferation of infectious microbes. In this study, silver nanoparticles (Ag NPs) were conjugated onto the exterior side wall of functionalized carbon nanotubes (F-CNT) employing the one-step ultrasonication technique at 37°C for a duration of 6 h. Colloidal AgNPs were loaded onto the side wall of the F-CNT for the fabrication of Ag@CNT MOF. Fabricated Ag@CNT MOF nanocomposites were subjected to comprehensive characterization employing cutting-edge analytical methods, including UV-Vis, SEM, TEM, FTIR, Raman spectroscopy, and XRD. The antimicrobial efficacy of Ag@CNT MOF nanocomposites was assessed against Staphylococcus aureus by using well diffusion and microbroth dilution methods. The synthesized Ag@CNT MOF demonstrated enhanced antimicrobial activity against S. aureus bacteria. In our in vitro investigations, we observed significant inhibition zones with diameters of 43 mm ± 0.9 mm and 50 mm ± 0.4 mm at concentrations of 0.5 mg/mL and 1.0 mg/mL using the well diffusion technique. Additionally, there was a 78% decrease in bacterial growth of S. aureus when exposed to 128 µg/mL concentration of Ag@CNT. [ABSTRACT FROM AUTHOR]

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This paper examines the water-vapour diffusion resistance (Z-value) of vapour versus wind barriers by determining their Z-value ratio in exterior wood-frame walls thermally insulated with six different materials to prevent mould growth. Using WUFI Pro, the water-vapour diffusion resistance requirements were determined for thermal insulation using mineral wool and biogenic materials: wood fibre, straw, flax, grass, and hemp. Hygrothermal simulations determine the minimum Z-value ratio between these materials with vapour versus wind barriers in temperate and cold climates. Wind barriers with Z-values between 1 and 8 GPa s m2/kg were used in walls with U-values of 0.15 and 0.10 W/m2 K. The indoor moisture load was defined from classes of 1 to 5 with a U-value of 0.15 W/m2 K and classes of 2 and 3 were used for a U-value of 0.10 W/m2 K. The Z-value ratio depends on the Z-values of the wind barrier and thermal insulation material, moisture load class, and U-value. The required Z-value ratio declines with an increased wind-barrier Z-value. The vapour-barrier Z-value approaches a fixed threshold for wind-barrier Z-values approaching lower values (1 GPa s m2/kg) and those approaching higher values (8 GPa s m2/kg), depending on the thermal insulation material. This parameter study examines wind barriers with a Z-value ranging between 1 and 8 GPa s m2/kg, which characterises typical wind barriers used in Denmark For the water-vapour diffusion resistance requirement of the vapour barrier, the Z-value increases for increased moisture load classes and thermally insulated walls with lower U-values. The conversion between the Z-value, the Sd-value, and the water-vapour resistance factor µ can be found in DS/EN ISO 12572:2016. [ABSTRACT FROM AUTHOR]

Rising global energy demand has intensified the need for sustainable building practices and reduced energy consumption in the construction sector. This study investigates the energy-saving potential of integrating innovative materials into building wall structures in semiarid climates. Specifically, we examine the combination of thermal insulation made from recycled textile waste and phase change materials (PCMs) in exterior walls. Using the dynamic simulation tool TRNSYS, we analyzed heat transfer through the modified wall assembly under semiarid climate conditions typical of Marrakech, Morocco. Our results show that this "bioclimatic" design significantly impacts cooling loads more than heating demands. The modified building achieved a 52% reduction in summer energy usage compared to a conventional reference building. This energy saving translates to a 39% decrease in greenhouse gas emissions. Importantly, this study confirms that this configuration maintains thermal comfort for occupants, with particular effectiveness during the hot summer months when cooling demands are highest. [ABSTRACT FROM AUTHOR]

AbstractPurple maize is a pigmented variety rich in antioxidants. Arabinoxylans (AX) are prebiotic compounds also found in the grain wall that can form gels. Recently, antioxidants have extensively been studied for their beneficial effects. However, these bioactive compounds do not easily reach the intestine in a stable form. These gels can protect certain compounds during in vitro digestion. This work aimed to extract the AX and simultaneously obtain the antioxidant compounds present in the external walls of the purple maize grain to produce gels with 2% and 4% AX to apply an in vitro digestion method. Popcorn maize (unpigmented) was used as a control. The amount of ferulic acid, polyphenols, and anthocyanins, and their antioxidative activity, were measured at in vitro digestion of the gels. This work highlights the ability of AX gels to enhance the potential bioavailability of antioxidant compounds including anthocyanins from purple maize after digestion. [ABSTRACT FROM AUTHOR]

Sustainable construction practices rely on carefully selecting building materials and balancing environmental and economic considerations. This study examines the complex link between local climate, market dynamics, and building material selection. Market data analysis, parametric modeling, and brute‐force optimization are used to provide insights into construction decision‐making. Across 5540 simulations, a thorough assessment of the financial and energy performance of various materials for walls, roofs, windows, and floors is conducted. Incorporating Pareto ranking, parallel simulation, and sensitivity analysis, the comprehensive evaluation reveals the intricate tradeoffs between cost, thermal properties, and energy savings. The findings highlight the potential for optimal external wall solutions to reduce U‐values by up to 30% and achieve source energy savings of up to 25% source energy savings across diverse climates. By emphasizing the importance of local context in material selection, this study highlights how energy consumption patterns and transmission losses influence financial and energy performance, thus advancing sustainable construction practices. [ABSTRACT FROM AUTHOR]

Background: Insecticides are sprayed on external building walls for treatments against crawling and flying insects. These applications can lead to drift into non-target areas and thus to undesirable environmental pollution. This emission pathway needs to be considered during exposure assessments within product authorisations to assess potential environmental risks. However, now, there is only one default value for deposition that is used in all calculations based on the Emission Scenario Document of the Organization for Economic Co-operation and Development at a distance of 50 cm to the treatment area. This is not sufficient for a risk assessment. Results: When applying a chemical barrier of 50 cm at the bottom of the building wall, wind direction had the greatest influence on drift, while changing the nozzle type had no significant effect. Compared with the measured ground sediments, the OECD default value was deemed to be realistic at a distance of 57 cm from the treatment area. When treating the entire building wall, the wind direction as well as the nozzle used show significant influence on the measured values of drift. The default value for deposition proposed for modelling environmental exposure in OECD document ESD PT18 No. 18 was exceeded. Thus, the exposure estimation might not be protective enough. Conclusion: Drift values used for the environmental exposure assessment of biocidal products during treatments of building walls should be adapted. This is especially relevant for treatments of entire building walls, where the current default value was exceeded for all distances from the building wall. Wind direction and nozzle type can reduce environmental impact. This finding can be used as a measure to reduce unnecessary exposure in the environment in the future. [ABSTRACT FROM AUTHOR]

An optimization study on thermal insulation applied to building exteriors has been performed in this research. Solar radiation has been considered while obtaining optimum insulation thicknesses for various directions. Analyses have been conducted not only for the cardinal directions (south, north, west, and east) but also for the intermediate directions (southeast, northeast, northwest, and southwest). Solar radiation received by vertical walls and cooling and heating degree day values have been computed according to directions. This research examines the most suitable insulation thicknesses for different seasonal usage scenarios, considering cooling, heating, and annual energy demands. Variations in energy cost savings, savings rates, payback periods, seasonal energy demands, and optimum insulation thicknesses for various wall orientations have been presented. Additionally, correlations providing the total cost based on the applied insulation thickness for each direction and various building usage scenarios have been determined. The results indicate that incoming solar radiation varies from 52.08 W/m2 to 111.82 W/m2 across different wall orientations, while energy cost savings range from 23.48 USD/m2 to 24.56 USD/m2, with savings rates between 69.8% and 70.3%. Payback periods range from 5.94 to 6.05 years. Depending on the wall orientation, optimum insulation thicknesses vary between 4.52 and 5.02 cm for heating, 1.56 and 2.09 cm for cooling, and 5.92 and 6.08 cm for annual energy requirements. The heating energy demands ranged from 54.8 MJ/m2 to 58.38 MJ/m2, while the cooling energy demands varied between 10.91 MJ/m2 and 12.08 MJ/m2, depending on the wall orientation. It has been concluded that the ideal insulation thicknesses for meeting cooling, heating, and annual energy demands vary depending on the wall orientation and the building's use purpose. [ABSTRACT FROM AUTHOR]

The current study used degree-day method to determine the optimum insulation thickness for different insulation materials. Some of the commonly used insulation materials available in the market are considered in the study. Materials used in the study are, fiberglass rigid, urethane rigid, fiberglass urethane, perlite, and extruded polystyrene. The cooling degree days were calculated using the base temperature varies from 18°C to 26°C for the four major cities like Mumbai, New Delhi, Kolkata, and Chennai of India. The study aims to analyze the effect of the number of cooling degree days and base temperature on insulation thickness and also determine the variation of annual cooling cost with the insulation thickness. The result shows that the optimum insulation thickness varies with the cooling degree days and is also influenced by the electricity rate and the cost of insulation material. Based on the result, it is found that optimum insulation thickness is affected by the thermal conductivity of the material, base temperature, CDD, material cost, and fuel cost. The result shows best suitable insulation materials for Delhi, Mumbai, Kolkata, and Chennai are urethane rigid, fiberglass urethane, urethane rigid, and fiberglass rigid respectively. The optimum insulation thicknesses vary between 1 and 12 cm for the different base temperatures and cities. Annual cooling cost per m2 is calculated for the base temperature 21 °C and 24 °C, and the result shows that fiberglass urethane has the lowest annual cooling cost for different cities. Energy-saving varies with the thickness of the insulating materials apply on the wall. In addition with the help of insulation, energy can be saved up to 80% and achieve energy-efficient buildings. [ABSTRACT FROM AUTHOR]

Phosphogypsum (PG) is a solid waste generated by phosphate fertilizer industries that is currently used in concrete materials. However, adding PG to concrete usually results in reducing its water resistance and corrosion resistance. This paper presents a new method of applying PG to concrete to improve its water resistance. In this paper, a green superhydrophobic PG (SPG) coating was prepared using modified PG as a hydrophobic medium and cement as the bonding material. The contact angle between the superhydrophobic phosphogypsum coating (SPG coating) and water was 156°, and the coating reached a superhydrophobic state with good self-cleaning ability. Even when sandpaper was used to polish the coating, the water contact angle of the coating was still greater than 150°, indicating that the coating had good wear resistance. In addition, the results of water absorption and electrochemical experiments indicated that mortar coated with SPG had better water resistance and corrosion resistance than ordinary mortar. The SPG coatings with water resistance, wear resistance, and self-cleaning properties have potential applications in building exterior walls. [ABSTRACT FROM AUTHOR]

The problem of reducing primary energy consumption is increasingly discussed in the technical literature. Relatively large amounts of energy are used to heat rooms. In the case of resources of much cheaper waste energy or energy from renewable sources with a temperature lower than required in the rooms, the so-called "thermal barrier" placed in external walls can be used to reduce heat transmission losses. The thermal barrier is a vertical wall element with pipes with a heating medium installed in the partition, with a temperature lower than the temperature in the room but higher than that resulting from the heat transfer through the partition without a barrier. An analytical calculation of heat flow through a thermal barrier has not been encountered in the literature. Therefore, a methodology for thermal barrier calculations was developed. In the paper, the heat fluxes flowing from the room to the partition and from the partition to the outside are determined. The developed model of partition with thermal barrier is then presented and the formula for thermal barrier efficiency is derived. Based mainly on theoretical models for the assumed input values and the partition's surroundings it was found that the efficiency of the thermal barrier does not depend on the temperatures of the barrier base and the wall environment, but only on the geometrical and thermodynamic parameters of the partition. It has also been shown that the efficiency of the thermal barrier is the highest when the resistance of the partition on both sides of the barrier is the same. It should be noted that the total amount of heat given off by a wall with a thermal barrier is greater than through a wall without a barrier, but the costs of heating the room may be lower. [ABSTRACT FROM AUTHOR]

For thousands of years, mortar-based materials — including bedding mortars, plaster floors, internal wall plasters, external wall renders and stuccos, and concrete — have been key construction materials in many cultures throughout the world. This paper gives an overview and examples of the use and development of mortar-based materials in cultures across the Middle East, Europe, Asia, and Mesoamerica, prior to the development of hydraulic cements in the late 18th and early 19th centuries. [ABSTRACT FROM AUTHOR]

Wood is known for its complex hygroscopic properties. Previous studies show that both the temperature-dependency and the hysteresis in sorption should be included in the physical models, if the most accurate results are desired from simulations of building assemblies with wood-based materials. Literature is scarce on the topic, where the significance of these aspects on the reliability of mould-risk assessments is inspected. Exterior walls with glass wool insulation and LDF-sheathing were studied by using two different models with previously measured material data. Over 300 hygrothermal simulations were carried out, where mould-indices were computed on the warm side of the sheathing. According to both conventional and more sophisticated model, the studied walls perform well in cold climate if no driving rain leaks in. Temperature-dependent and hysteretic model yields slightly smaller mould-indices in general, but for certain leaky cases the difference is significant, which indicates the importance of sophisticated sorption-properties in modelling. [ABSTRACT FROM AUTHOR]

Facility agriculture, which involves agricultural production in controlled environments such as greenhouses, indoor farms, and vertical farms, aims to maximize efficiency, yield, and quality while minimizing resource consumption and environmental impact. Energy-saving technologies are essential to the green and low-carbon development of facility agriculture. Recently, phase change heat storage (PCHS) systems using phase change materials (PCMs) have gained significant attention due to their high thermal storage density and excellent thermal regulation performance. These systems are particularly promising for applications in facility agriculture and related buildings, such as solar thermal utilization, greenhouse walls, and soil insulation. However, the low thermal conductivity of PCMs presents a challenge for applications requiring rapid heat transfer. This study aims to provide a comprehensive review of the types, thermophysical properties, and various forms of PCMs, including macro-encapsulated PCMs, shape-stabilized PCMs, and phase change capsules (PCCs), as well as their preparation methods. The research methodology involves an in-depth analysis of these PCMs and their applications in active and passive PCHS systems within facility agriculture and related buildings. The major conclusion of this study highlights the critical role of PCMs in advancing energy-saving technologies in facility agriculture. By enhancing PCM performance, optimizing latent heat storage systems, and integrating intelligent environmental control, this work provides essential guidelines for designing more efficient and sustainable agricultural structures. The article will serve as the fundamental guideline to design more robust structures for facility agriculture and related buildings. [ABSTRACT FROM AUTHOR]

The energy consumption of residential buildings plays a crucial role in overall energy consumption and environmental sustainability. This paper aims to conduct an energy analysis of a residential house located in China, with a focus on comparing the accuracy of the model, identifying areas for improvement, and proposing energy-efficient solutions. Four sets of temperature sensors were placed to monitor the ambient temperature at which the building is located and the indoor temperature of the residential building during a heating season. The energy consumption of keeping the building running at a low temperature was recorded and compared with the simulation results to verify the accuracy of the model. The monitoring results give the weekly average temperature of each zone on each floor, and the door and window positions, room layouts, and orientations are discussed to analyze the thermal response of the building. In addition, the effect of the heat transfer coefficient of the exterior walls, the heat transfer coefficient of the roof, and the solar heat gain coefficient (SHGC) of the exterior windows on the heating energy consumption of the building are further analyzed through simulations. The results show that, after adding a certain thickness of insulation to the exterior walls and roofs of a building, increasing the thickness of the insulation layer produces little extra energy saving. The use of building windows with high SHGC can effectively reduce building heating energy consumption. [ABSTRACT FROM AUTHOR]

Enhancing the energy efficiency of building envelopes is one of the key strategies for energy conservation and reducing consumption in buildings. This study employs numerical research methods to explore the impact of crucial factors such as solar cell coverage, air channel height, indoor relative humidity, and indoor wind speed on the power generation performance and thermal comfort of a photovoltaic (PV)—Trombe wall. The dynamic changes in optical and thermal performance and energy efficiency matching mechanisms of this system are also discussed in hot summer and warm winter regions. The research findings indicate that the periods of good thermal comfort and power generation efficiency for humans are from 9:00 to 17:00 in winter. In summer, these periods are from 5:00 to 8:00 as well as from 17:00 to 20:00. When the system height is 2 m, the electricity price for power supplied by the PV—Trombe wall system is 25% lower than the residential price, with an annual energy generation of 322.5 kWh/m2 of solar panel, which can save USD 6.35 in costs. Moreover, an experiment is conducted to investigate the thermoelectric correlation by constructing a traditional Trombe wall and an external PV—Trombe wall. When the coverage reached 52.08%, the overall system efficiency was maximized. At a coverage of 78.12%, the system's thermal efficiency was at its lowest, while the maximum power generation was 510.3 W. It can be seen that the PV—Trombe wall possesses good economic benefits and energy saving as well as emission reduction potential in hot summers and warm winters regions, and the smooth implementation of related works will effectively promote its applications and promotions. [ABSTRACT FROM AUTHOR]

Buildings are one the largest energy-consuming sectors in the world, and it is crucial to find solutions to reduce their energy consumption. One way to evaluate these solutions is using building simulation software, which provides a comprehensive perspective. In this article, using DesignBuilder software (v 6.1), the effect of using phase-change materials (PCMs) on the external walls and ceiling of the Department of Mechanical Engineering of Shahid Beheshti University (Tehran, Iran) has been investigated. The methodology involves the use of a layer of PCMs for three locations: (1) on the walls; (2) on the ceiling; and (3) on both the walls and ceiling, with/without PV panels, which leads to seven scenarios (alongside the reference one). The result shows that using PCMs has a greater impact on the heating load than the cooling one and is more effective on ceilings than walls. For the simultaneous use of PCMs in the ceilings and walls, the heating and cooling loads, in comparison with the initial condition of the building, are reduced by 24%, and 12%, respectively. When using solar panels, the heating load increases by 12.6%, and the cooling load decreases by 8.6%, whereas the total energy consumption of the building is fairly constant when using both PV panels and PCMs. In these last conditions, the primary evaluated values shifted significantly. Notably, CO2 emissions saw a nearly 50% reduction, making the simultaneous use of PV panels and PCMs on both walls and ceilings the best performance option. [ABSTRACT FROM AUTHOR]

Traditional concrete buildings exhibit low energy consumption and high heat loss, which results in a larger environmental problem. Precast insulation walls are proposed for strengthening thermal insulation efficiency and mitigating heat loss. Numerous studies have investigated the thermal performance of insulation walls over the past decades. However, gaps remain in practical engineering applications. This study aims to bridge these gaps by providing practical design recommendations based on experimental research. Nine different types of precast insulation walls were tested to examine the thermal performance, and the parameters of the insulation material, insulation form, insulation layer thickness, and concrete rib width were investigated. Then, numerical models of these walls were developed for simulating the thermal performance of the tested specimens. Finally, a six-story student apartment model using designed walls was developed to assess energy consumption in two distinct climate zones: the hot summer and cold winter zone of Changsha City, and the cold zone of Harbin City. The results indicate that the precast insulation wall with external insulation form shows better thermal performance than the sandwich insulation form. It is recommended to use precast insulation walls with 50 mm extruded polystyrene (XPS) external thermal insulation form in Changsha City and 80 mm XPS external thermal insulation form in Harbin City. Furthermore, buildings using precast insulation walls can significantly reduce energy consumption by 49.25% in Changsha and 49.38% in Harbin compared to traditional concrete wall buildings. Based on these findings, suitable design suggestions for this precast concrete wall panel building composed of insulation walls are given. [ABSTRACT FROM AUTHOR]

Sludge ceramsite (SC) can be utilized as a lightweight aggregate in concrete, especially in external wall materials, due to the increasing volume of polluted sludge, which contributes to water system deterioration and poses greater threats to human health. The influence of the fresh mortar's slump flow on the dispersion of ceramsite was studied. The ultrasonic sound velocity, capillary water absorption rate, compressive strength, and coefficient of variation (CV) were measured in this study. Thermogravimetric (TG) analysis, ultra depth-of-field microscope scanning, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS) were used to analyze the performance mechanism of the ceramsite concrete. The results indicated that adding SC could reduce the fluidity of the fresh concrete, with a reduction by rates of up to 2.04%. The addition of WRA could improve the fluidity by rates of up to 60.77%. The relationship between the ultrasonic sound speed and the increasing fluidity could be deduced as a negative correlation. The water absorption was negatively correlated with the compressive strength. The concrete with a slump flow of 12.35 and 12.5 cm reached the maximum compressive strength, which had the lowest water absorption, and demonstrated internal homogeneity. The optimum slump flow was 12.35 and 12.5 cm. With the slump flow of 12.5 cm, the corresponding CV was the lowest, showing the optimum SC's dispersion. Through TG, XRD, and SEM analyses, it was verified that the addition of 0.6% WRA promoted the hydration of cement. In addition, SC increased the hydration products. [ABSTRACT FROM AUTHOR]

The side junctions of metal-plastic block frame windows to the walls of residential buildings at different positions of window frames in the wall cavity are analysed. The duration of thermal failure state by the condensate formation criterion was used as a probabilistic indicator of reliability. The units of uninsulated walls, erected in the second half of the 20th century, have a clearly insufficient thermal reliability level. Thermal insulation of walls according to current design standards in most cases ensures an acceptable of the thermal failure state duration. [ABSTRACT FROM AUTHOR]