Building Insulation Materials Research Articles

Design of Perlite Based Thermal Insulation Plate and Determination of its Physical, Mechanical and Thermal Properties

According to the current fire regulations in Turkey, the use of insulation materials such as EPS, which are commonly employed in building insulation, is limited to buildings up to 28.5 m in height. The regulations mandate the use of Class A fire-resistant thermal insulation materials in high-rise buildings. However, these materials may present challenges in terms of application and sustainability. This study aims to develop a perlite-based thermal insulation board that is Class A fire-resistant, competitive with traditional insulation materials, and possesses optimal physical, mechanical, and thermal properties. In the production of the specimens, expanded perlite, liquid sodium silicate, and silicon powder were used, and tests for apparent density, compressive-flexural strength, capillary water absorption, and thermal conductivity were conducted in accordance with EN standards. In the first stage, the produced specimens were subjected to four different activation temperatures to determine the optimal process temperature. In the second stage, the ratios of perlite, sodium silicate, and water were varied to achieve the mixture design that yielded the highest mechanical properties from the specimens. In the final stage, water-repellent admixtures were incorporated into the batches at mass ratios of 1.5 %, 3 %, 4.5 %, and 6 %. The perlite-based thermal insulation board, which offers optimal properties in the most cost-effective manner, has an apparent density of 127 kg·m−3, compressive strength of 266 kPa, flexural strength of 156 kPa, capillary water absorption value of 0.0197 kg·m−2·min−0.5, thermal conductivity of 0.0475 Wm−1·K−1, and a unit cost of 97 $ m−3. Consequently, the insulation board developed in this study presents a viable alternative to conventional insulation materials, offering Class A fire resistance.

Theoretical Modelling, Experimental Testing and Simulation Analysis of Thermal Properties for Green Building-Insulation Materials

In this study, 45 alternative green materials for building walls were experimentally produced, utilizing renewable (epoxidized sesame oil), natural (clay), and waste (Seyitömer fly ash) resources. These materials were evaluated based on key technical properties such as mass, tensile-compressive strength, and thermal conductivity, all of which are essential for construction and insulation applications. Subsequently, theoretical modeling was conducted for the material coded SE45, which demonstrated the lowest thermal conductivity. Through mathematical calculations, the theoretical thermal conductivity value was determined with a deviation of +5.88%. Furthermore, 48 alternative scenarios were designed for three different building envelope types (internally insulated, externally insulated, and sandwich), using commonly used building insulation materials alongside the sesame oil-based green material with the lowest thermal conductivity (SE45). Energy performance evaluations were conducted by analyzing temperature distributions along the walls of all designed scenarios using ANSYS simulations under the climatic conditions of Ankara, Turkey.

Improving Combustion Analysis of Extruded Polystyrene via Custom Isolation Methodology

This study is dedicated to an in−depth analysis of the combustion characteristics of extruded polystyrene (XPS) as a building insulation material with the aim of accurately assessing its fire risk in the built environment. Innovatively, this research employed a cone calorimeter equipped with a self−designed insulating sample holder to conduct a systematic experimental study. Additionally, it performed a comprehensive analysis of the ignition characteristics, heat release rate, fire hazard, smoke release, and toxic gas emission of XPS materials. The experimental results revealed that the combustion behavior of XPS is influenced by multiple factors, including the content of flame retardants and external heat flux, which significantly affect the fire hazard of XPS. When the thermal radiation intensity escalates from 25 kW/m2 to 55 kW/m2, the peak heat release rate of XPS−B1 rises from 428 kW/m2 to 535 kW/m2, marking an increase of 25.00%. Conversely, the peak heat release rate of XPS−B2 surges from 348 kW/m2 to 579 kW/m2, reflecting a substantial increase of 66.38%. This research not only provides a solid theoretical foundation and detailed experimental data for the fire behavior of XPS materials but also holds significant practical importance for enhancing the fire safety of buildings. Overall, this research contributes to the scientific understanding of XPS insulation materials and supports the development of more effective fire prevention measures in construction.

Investigation of hygrothermal behavior of a novel bio-based panel: Experiment and numerical simulation

Straw composites, owing to their low carbon footprint and favorable hygrothermal properties, are becoming a promising alternative insulation material for buildings in order to promote energy saving and occupants’ comfort. However, the heat and moisture characteristics of straw composites at the material scale and under steady-state condition are insufficient for a thorough assessment of their performance as a building component in actual service conditions. This study focused on the hygrothermal performance of a novel bio-based wall made with a rice straw–alginate composite material. The temperature and relative humidity profiles within the wall were monitored under various boundary conditions. The inverse analysis method was proposed to determine liquid water permeability. In in a dynamic test, compared with the model of coupled heat-and-moisture transfer (CHM), the transient heat transfer model predicted temperature profiles with higher errors and underestimated total heat flux by up to 30.6%. Also, under the dynamic condition, the CHM model with liquid water transport showed decreased mean absolute errors by 61%, 57% and 8% at depths of 28 mm, 36 mm and 64 mm, respectively, compared with those predicted by the CHM model without liquid water transport. Both vapor transport and liquid transport seemed to be essential when modeling thermal transfer and moisture transfer through the wall.

Corrigendum to “Size effect of typical hygrothermal properties test values for building insulation materials” [Energy Build. 325 (2024) 115049

Corrigendum to “Size effect of typical hygrothermal properties test values for building insulation materials” [Energy Build. 325 (2024) 115049

A Literature Survey on Advanced Insulation Material In Buildings

Insulating materials have an important role in maintaining the thermal efficiency of buildings by limiting heat transfer and energy consumption. This research explores the latest innovations in building insulation materials that can improve energy efficiency and sustainability. The aim of this research is to analyze the latest developments in building insulation materials, as well as explore the potential use of eco-friendly materials that have minimal environmental impact. The research method involved a comprehensive literature review of academic articles, research papers, and other relevant sources to gather information regarding innovative insulation materials being developed. The results show that insulating materials such as aerogels, vacuum panels, and phase change materials have high thermal performance and good durability. In addition, the use of sustainable materials such as recycled paper and natural fibers is gaining popularity among architects and developers. The application of advanced and environmentally friendly insulation materials is essential to improve the energy efficiency of buildings and reduce environmental impact. By utilizing innovative technologies and materials, we can create a more sustainable living environment for future generations.

Toward a Greener Building Envelope: Analyzing Sustainable Cladding Materials through BIM for Energy Efficiency

The proper building materials used in the building envelope provide better thermal and energy efficiency of the building by allowing for better thermal regulation between the inside and exterior. The scope of this research involves the optimization of the building envelope’s features to enhance the thermal ambiance and lower the energy requirements of residential structures in a specific environment. Critical design choices include the facade cladding system and building insulation materials. In order to select the most effective facade cladding system among widely used materials in the Black Sea climate conditions, this study attempts to develop sustainable design options by building information modeling of a sample site security cabin modeled with the BIM-based Autodesk Revit software, followed by a building energy model. Finally, building energy simulation was carried out with Green Building Studio, which can be integrated with the Autodesk Revit program. The heating, cooling, and total energy consumption of the sample site security cabin project were determined by the analysis. Seventy-two alternative designs resulting from eight different coating materials, three commercial insulation materials, and three different structural materials were evaluated. In terms of energy efficiency, EPS and siding were obtained as the most effective insulation materials and coating materials for Trabzon province. This way, it has been aimed to provide the designers with the information through the sample project for the buildings to be designed in the determined climatic conditions.

Utilization of graphite tailings and coal gangue in the preparation of foamed ceramics

AbstractTo enhance the effective utilization of graphite tailings and coal gangue (CG), both considered typical industrial solid waste materials, we synthesized foamed ceramics incorporating these materials. The optimization process led to improvements in compressive strength, water absorption, and thermal conductivity by regulating critical parameters, including the proportions of SiC and Na2O, as well as the duration of ball milling. Employing techniques such as X‐ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, we investigated the phase composition, high‐temperature reactions, and microstructural characteristics of the foamed ceramics. The incorporation of graphite tailings (GT) facilitated the formation of a rich network of pore structures and amorphous glass phases, which enhanced the lightweight nature, mechanical strength, and thermal insulation properties of the foamed ceramics. By analyzing the GT content as a variable, we determined that the G50C40 (GT:CG:potassium feldspar = 40:50:10) sample exhibited optimal performance overall. Under these experimental conditions, the foamed ceramic demonstrated a bulk density of 0.749 g/cm3, a compressive strength of 12.37 MPa, a thermal conductivity of 0.21 W/(m·K), and a water absorption rate of 0.79%. Therefore, it is posited that GT possesses considerable potential to broaden the application spectrum of foamed ceramics within the domain of building insulation materials.

Fire performance and characterization of geopolymer foams using fly ash and coal gangue

The paper introduces foamed geopolymers as effective thermal insulation materials for buildings, with the ability to withstand high temperatures. The production methods for achieving a porous microstructure in geopolymers are discussed, emphasizing the use of foaming agents like aluminium powder. The presented research focuses on developing geopolymer foams from industrial waste materials [fly ash and coal gangue] with enhanced thermal and fire resistance while maintaining robust mechanical properties. The novelty lies in evaluating these foams at a medium-sized panel scale [750 mm x 750 mm x thickness] and assessing their fire resistance through comprehensive tests, differentiating it from existing literature that primarily explores smaller-scale materials. Class F fly ash from Skawina power plant, Poland and waste rock from coal mining KWK Wieczorek, Katowice, Poland were used for preparation of geopolymer foam. The research aims to contribute insights into the fire performance of geopolymer foams under ISO 834-1 fire scenario, paving the way for potential applications as thermal insulation panels in building facilities. Results from fire exposure tests, post-fire mechanical property assessments, SEM observations, EDS analyses, XRD analyses, as well as ageing effects are presented and discussed. While foamed geopolymers demonstrate resilience and fire resistance, variations in their mechanical properties and microstructure due to fire exposure are highlighted. The research underlines the potential of employing geopolymer foams as a sustainable solution for thermal insulation in construction, opening up further exploration and application in the construction industry.

Experimental Research on a Feasible Building Insulation Material Based Reed in China

Experimental Research on a Feasible Building Insulation Material Based Reed in China

Comparison of Thermal Conductivity and Long-Term Change of Building Insulation Materials According to Accelerated Laboratory Test Methods of ISO 11561 and EN 13166 Standard

The insulation performance of a building is one of the most fundamental factors in reducing its energy use. The insulation of the building envelope is the main factor that directly affects the cooling and heating loads, which is responsible for the largest portion of the building’s energy consumption. Recently, in South Korea, building insulation materials such as PIR and PF, which have not only fire resistance but also high insulation performance, are becoming mainstream in the industry as fire safety standards have been strengthened. However, there are concerns about the long-term change of high-performance insulation materials. In particular, in contrast with existing plastic insulation materials such as EPS and XPS, the evaluation of the reliability of the long-term change of insulation materials with a high closed-cell rate is becoming an issue. This is because, unlike the existing EPS and XPS, there are insufficient international standard test methods for evaluating the long-term thermal performance of composite insulation materials such as polyurethane and phenol. They are combined with layers of other types of thermal insulation and/or one or both of the surfaces are covered with coatings, facings, membranes or other surface skins, all serving some functional purpose depending on the product application. In this study, the long-term change of building insulation materials was tested and analyzed based on the standard of the accelerated aging test. Four types of building insulation materials were used in the experiment: EPS, XPS, PF and PIR. The accelerated aging tests were conducted based on ISO 11561 and BS EN 13166 standards (accelerated laboratory test methods). The results of the accelerated aging tests for the materials were analyzed and the thermal resistance of the insulation materials was also compared. From the test results according to the slicing test method specified in the ISO 11561, the thermal resistance of EPS, XPS, PF, and PIR with long-term changes decreased by 2.4%, 8.5%, 16.4%, and 18.0%, respectively, compared to the initial thermal resistance. From the test results according to the 70 °C heat acceleration test method specified in the EN 13166, the thermal resistance decreased by 2.0% for EPS, 6.7% for XPS, 8.7% for PF and 13.6% for PIR, compared to their respective initial thermal resistance values. The EPS showed highly similar thermal resistance changes for the two different test methods. It was found that there was no effect from the slicing of the insulation material, and the accelerated aging test showed minimal changes in thermal resistance. In contrast, the other insulation materials exhibited different thermal resistance changes depending on the test method, with each material showing a thermal resistance change of 8.8% to 15.9% when subjected to the accelerated aging test.

Size effect of typical hygrothermal properties test values for building insulation materials

Thermal and moisture properties of building insulation materials are crucial input parameters for analyzing thermal and moisture transfer phenomena in building environments. Accurate determination of these parameters under different conditions is essential for the correct application and assessment of materials and envelope structures. However, numerous factors influence thermal and moisture properties, and while extensive research has been conducted on this topic, the effects of specimen size on typical thermal and moisture property test values remain unclear. To address the issue of unreliable data caused by random specimen sizes in thermal and moisture property testing of building insulation materials, this study selects three materials—expanded polystyrene (EPS), extruded polystyrene (XPS), and foamed cement—as test subjects to explore the size effects on typical thermal and moisture property test values. The results indicate that specimen size significantly affects the test values for typical thermal and moisture properties, with only a few experiments showing negligible size effects for certain materials. For foamed cement, recommended specimen sizes for thermal conductivity testing using the guarded hot plate method and the transient plane source method are 300 × 300 × 30 mm and 50 × 50 × 30 mm, respectively. Except for equilibrium moisture absorption experiments, the weight of other moisture property tests is generally represented by thickness > planar dimensions.

Preparation and properties of phosphogypsum-based calcined coal gangue composite cementitious materials

Phosphogypsum (PG) and coal gangue (CG), as the largest solid waste today, the effective utilization of this part of the resource can help to alleviate environmental pollution and resource waste. The aim of this study was to utilize the excellent thermal insulation properties of original PG and the regulation of hydration products by calcined coal gangue (CCG) to produce phosphogypsum-based calcined coal gangue composite cementitious materials (PBCM). The optimal ratio of PBCM was studied through a combination of mechanical properties and thermal insulation properties. Finally, the effect of the foam factor is further investigated. The results show that: CCG can be used as a silicon-rich material with gelling properties to regulate the hydration products generated. The test block with a foam content of 8 % has the best performance, with a compressive strength of 2.53 MPa and a thermal conductivity of 0.1427 W/(m·K). The optimal experimental scheme obtained from the orthogonal test was as follows: The optimal experimental design obtained from orthogonal experiments was as follows: PG, quicklime (QL), sulfoaluminate cement (SAC) and foam contents were 45 %, 8 %, 8 % and 8 %, respectively. The CCG: cement and water-solid ratios (W/S) were 3:7 and 0.275, respectively. The development of high-performance composites presented in this study is conducive to enhancing waste utilization and provides a novel approach as well as a theoretical foundation for insulating building materials in practical engineering applications.

Natural fibers as promising core materials of vacuum insulation panels

To reduce energy consumption in buildings, this paper investigates the feasibility of using natural fibers as cost-effective, environmentally sustainable core materials for vacuum insulation panels (VIPs). First, a comprehensive experimental study was conducted for 10 potential natural fiber candidates. The thermal conductivities of the 10 natural fiber mats at various vacuum pressures were measured; their compression and morphology properties were quantified. In addition, an analytical model was used to explore the major factors that influence the thermal conductivity of natural fibers as a function of internal air pressure. Results show that recycled cotton, kapok, and bamboo fibers are ideal candidates for VIP core materials; at <0.05 Pa, their thermal conductivities varied between 2 and 4 mW/(m⋅K). Furthermore, for some fibers, thermal conductivity was inversely proportional to fiber density. For the selection of fiber materials for VIP cores, the ideal fiber candidate has a small fiber diameter and a low fiber mat density. Based on thermal measurements, even though the internal air pressure of 5 Pa was enough to attain the minimum thermal conductivity, obtaining internal air pressure below 5 Pa is recommended for prolonged service life, considering small leaks of VIP package barrier films and potential off-gassing from fibers. The simulation results predicting the effective thermal conductivities matched the experimental results well. These findings indicate that natural fiber–based VIPs have the potential to be a sustainable, inexpensive alternative to the current technologies in building insulation materials.

Facile construction of superhydrophobic porous red mud/slag-based geopolymer for thermal insulation and oil/water separation

Red mud (RM) is difficult to be comprehensively utilized and has a serious impact on the environment due to the high alkalinity, low activity, and high content of harmful substances. In this study, porous RM-based geopolymers (PRGMs) with high porosity ratio (76.83%) and compressive strength (1.16 MPa) were prepared by controlling the ratio of slag and RM (60%) and curing temperature (70 °C) and adding a mechanical foaming agent (MFA: 12%). The flux of the PRGMs was as high as 10180.33 L·m-2·h-1 at a thickness of 3 mm. The equilibrium cold surface temperature was reduced from 175.6 to 131.7 °C compared to a structure without MFA. In addition, a superhydrophobic PRGMs (SPRGMs) was successfully modified by chemical vapor deposition using water and polymethylhydrosiloxane at 120 °C for 3 h. It had excellent superhydrophobic properties (159.04°) and low thermal conductivity (0.1922 W·m⁻1·K⁻1). The contact angle of the SPRGMs was still >150° even after treatment under real simulation conditions including acid/alkali/salt solution contact/immersion, variable temperature (-20 to 450 °C for 2 h), ultraviolet aging (60 h), and physical abrasion (10 cycles). The SPRGMs achieved 100% desorption of light/heavy oils with excellent and stable cycling performances. The contact angle was still larger than 151° after 10 cycles. Furthermore, the SPRGMs are effective for a continuous treatment of oil/water emulsions and mixtures by gravity, which provides a new concept for the development of thermal insulation building materials, large-scale treatment of RM, and industrial treatment of oil/water pollution.

Research on preparation and microscopic mechanism of heat-insulating & flame-retardant EP/PI composite aerogel

Polyimide aerogels, with their lightweight, thermal insulation, and flame-retardant properties, have found extensive applications in aerospace, military, and other fields. However, their use in the building insulation materials market is rare. This paper focuses on polyimide (PI) aerogels and incorporates expanded perlite (EP) of different mesh sizes and qualities to prepare expanded perlite/polyimide (EP/PI) aerogels, aiming to enhance the performance of building insulation materials and reduce energy consumption in buildings. The research results indicate that the incorporation of EP not only protects the aerogel framework from complete destruction and improves its high-temperature stability but also significantly affects the pore distribution of PI aerogels. Specifically, doping a mass of 0.2g of expanded perlite with a mesh size of 80 can increase the specific surface area of PI aerogels by 15 times, effectively increasing the number of pores and the quantity of non-communicating pores in the aerogel, while also reducing the thermal conductivity of PI aerogels by 10 %, thereby hindering heat transfer and enhancing their thermal insulation and flame-retardant properties. To gain a deeper understanding of the thermal insulation mechanism of aerogels, the study combines molecular dynamics principles to analyze the diffusion of nitrogen molecules within the aerogel, thereby elucidating the heat transfer process and explaining the thermal insulation mechanism of EP/PI aerogels. Overall, the findings of this study demonstrate low density, low thermal conductivity, good high-temperature stability, and excellent thermal insulation and flame-retardant effects, indicating significant application potential and socio-economic benefits in building insulation materials.

Bioinspired polylactic acid/polyethylene glycol @ silicon dioxide microfibrous tarpaulin with dual-layer heterogeneous structure for enhanced daytime radiative cooling

Fibrous tarpaulin serves as the core barrier that protects goods, people, or areas from the adverse impacts of the external environment, such as rain, dust, and sunlight. However, conventional tarpaulins exhibit inadequate mechanical properties, a low solar reflectance, and are susceptible to pollution. To address these issues, a bioinspired polylactic acid/polyethylene glycol @silicon dioxide (PLA/PEG@SiO₂) microfibrous tarpaulin with a dual-layer heterogeneous structure was fabricated via in-situ drafting melt-blowing combined with thermal bonding, inspired by the layered structure of shells. This bioinspired dual-layer heterogeneous structure, with an adjustable heterodyne angle and SiO₂ size gradient, significantly improved the mechanical performance of the PLA/PEG@SiO2 microfibrous tarpaulin, and specifically manifested as an increase in the bursting strength of the sample to 25.5 N. Moreover, PLA/PEG@SiO2 microfibrous tarpaulin demonstrated excellent anti-pollution properties, effectively repelling liquids and dust. Additionally, its radiative cooling efficiency was notably enhanced, achieving a temperature reduction of ~9.8 °C compared with conventional fabrics, with reflectance of ~88.6 % and emissivity of ~98.3 %. These findings suggest that dual-layered PLA/PEG@SiO₂ microfibrous tarpaulin with multifunctional capabilities is a promising candidate for radiative cooling in outdoor shelters, wearable cooling devices, and energy-efficient building insulation materials.

Investigation of thermal, acoustic, mechanical, and radiation shielding performance of waste and natural fibers

It is crucial to address two pressing global issues, energy shortage and environmental pollution, when producing building insulation materials. Using waste and natural fiber groups can be part of the solution. The insulation material was produced using pumpkin fiber, chicken fiber, cotton waste, vermiculite, and epoxy as binders. The samples were tested for thermal conductivity coefficient, ultrasonic sound transmission rate, density, water absorption rate, compressive and bending strength, and fire resistance at temperatures of 75, 100, 125, and 150C. The samples produced using natural and waste materials yielded a thermal conductivity value of 0.041 W/mK, an ultrasonic sound transmission speed of 0.25 km/s, a compressive strength value of 1.57 MPa, and bending strength values of 0.91 MPa. It has been clearly demonstrated that, with its low volume loss, it can serve as an alternative to the EPS-XPS types available in the market. Furthermore, the linear attenuation coefficients (LAC) were examined to obtain radiation shielding properties of the samples at 1173 and 133 keV energies using a 60Co gamma source. Also, LAC values determined between 0,1167 ± 0,0452 cm−1-0,2315 ± 0,0065 cm−1 for 1173 keV and 0,1042 ± 0,0488 cm−1 - 0,2141 ± 0,0062 cm−1 for 1333 keV. Accordingly, it has been revealed that waste compositions are effective in protecting against radiation.

Energy-Efficient Geopolymer Composites Containing Phase-Change Materials-Comparison of Different Contents and Types.

The purpose of this study was to analyze the effects of phase-change components on the properties of geopolymer foams. Geopolymer foams are lightweight foamed geopolymers that are characterized by a high degree of porosity. Phase change materials, on the other hand, are compounds that, when added to a material, allow it to absorb, store, and then release large amounts of energy. Three types of PCMs, i.e., MikroCaps, GR42, and PX25, were introduced at 15% by weight. Geopolymer materials were produced based on silica fly ash, and hydrogen peroxide H2O2 was used to foam the geopolymer structure. The PCM geopolymer composites were cured at 60 °C. The produced materials were tested for physical, chemical, and thermal properties. The tests included oxide and mineral composition analysis of the base material, PCM particle size analysis, apparent density and porosity tests on the foams, water leachability tests, thermal tests (λ, Cv, Cp, α), and structural and textural analysis. The most relevant tests to confirm the performance of the phase-change materials were thermal tests. With the introduction of PCMs, volumetric heat capacity increased by as much as 41% and specific heat by 45%, and thermal diffusivity decreased by 23%. The results confirm the great potential of geopolymer composites as modern insulation materials for buildings and structures.

Tuning Rigid Polyurethane Foam with Eco-friendly Cellulose Nanocrystals from Oil Palm Empty Fruit Bunches as Energy-Efficient Material Composites for Buildings

The development of novel materials based on renewable materials with beneficial properties that assist with energy efficiency and conservation has been encouraged by increasing consciousness of environmental issues. This research intends to use sustainable cellulose nanocrystals (CNC) obtained from oil palm empty fruit bunches (OPEFB) as reinforcement to enhance the properties of rigid polyurethane foam (RPUF). RPUF reinforcement with varied CNC concentrations (0.25–1 wt%) was examined by foaming behavior, surface morphology, mechanical properties, thermal insulation properties, dimensional stability, efficiency energy study, and CO2 reduction through their thermal conductivity values. The results achieved an optimal improvement of mechanical properties of the RPUF composite by around 23.53% compared to RPUF control, at the addition of 0.5 wt% of CNC concentration while maintaining the density of 37–39 kg/m3. Further, incorporating CNC improved thermal insulating performance by 9.95%, as reflected by decreased thermal conductivity from 0.0292 W/mK to 0.0269 W/mK and decreased cell size by 28.12%. Finally, based on the energy and cost efficiency studies, RPUF-CNC composites offer up to 0.78 kWh/m2 and 0.031 kWh/m2 compared to conventional wall materials made of concrete and wood, respectively. Furthermore, it contributed to reduced greenhouse gas (GHG) emissions by 110 and 7.2 kg CO2/year compared to concrete and wood, respectively. This work demonstrates the promising use of eco-friendly building insulation materials to mitigate the energy and environmental crisis.