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Insulation materials’ contribution to the fire resistance of timber frame assemblies may vary considerably. At present, Eurocode 5 provides a model for fire design of the load-bearing function of timber frame assemblies with cavities completely filled with stone wool. Very little is known about the fire protection provided by other insulation materials. An improved design model which has the potential to consider the contribution of any insulation material has been introduced by the authors. This paper aims to analyze the parameters that describe in a universal way the protection against the charring given by different insulations not included in Eurocode 5.

A series of model-scale furnace tests of floor specimens for three different insulation materials were carried out. An analysis on the charring depth of the residual cross-sections was conducted by means of a resistograph device.

The study explains the criteria and procedure followed to derive the coefficients for the improved design model for three insulations involved in the study.

This research study involves a large experimental work which forms the basis of the proposed design model. This study presents an important step for fire resistance calculations of timber frame assemblies.

Sewing is the most widely used and preferred method for manufacturing clothing products for extreme weather conditions and other industrial insulation systems. Multiple layers of functional fabrics in combination with insulation materials are used to thermally insulate precious body heat from its surrounding cold environment. The sewing process fixes the insulation material between the fabric layers. During conventional sewing, the insulation material is compressed along the stitch line. With the compression of the insulation material, entrapped air is forced to leave the insulation material internal structure, and heat loss occurs along the entire length of the stitch line. It results in the deterioration of thermal properties of the end product along the stitch line.

The amount of air, which is a decisive factor for thermal properties of any insulation system, was investigated at the level of a unit stitch length of a lockstitch. Conventional microscopy methods are not suitable to study the compression along the stitch line. With the help of X-ray tomography, the three-dimensional data of a stitch was taken and studied to measure the volume of air. The samples were prepared with conventional lockstitch sewing and a newly developed innovative sewing method “Spacer Stitching.” The results are compared with each other in terms of the amount of air present in a unit stitch length.

Calculations based on X-ray tomography images of lockstitch and spacer stitch revealed that, in the case of lockstitch, a unit stitch has a 15% of its volume made up of material and 85% of its volume by air. In comparison, the spacer stitch with the same sewing and fabric parameters has a material volume of 4.6 % and an air volume of 95.4% in a single stitch.

The research can positively improve the thermal properties of sewn material made for insulating purposes of conventional clothing as well as of industrial insulations.

There is no literature available which investigates and calculates the amount of air and material present along with a stitch line.

The purpose of this paper is to examine the thermal insulation and water vapor transmission rate (WVTR) according to the type of the filling material, and compared the thermal insulation in the dynamic state considering actual wearing conditions.

The thermal insulation and WVTR were evaluated in a standard state depending on the type of filling material (goose down (GD), duck down (DD), Thinsulate700 (T700), Thinsulate600 (T600) and Polyester (PET)), and the changes in thermal insulation were examined by measuring the microclimate in the case of an environmental change from a high temperature to a low temperature. In addition, the clumping of filling material and the changes in the thickness/weight depending on the laundry process were observed, and the relationships with the thermal insulation were analyzed.

The results showed that for natural filling materials (GD and DD), the thermal insulation deteriorated significantly due to changes in the thickness/weight after laundering ten times, and water washing was more appropriate than the dry cleaning. On the other hand, the artificial filling materials (T700, T600 and PET) showed a relatively smaller difference, except for clumping, when they went through more dry cleaning or water washing cycles compared to the natural filling materials.

The results showed that the laundry methods have different effects on the damage to the filling material, the change in thermal insulation, and the change in the comfort-related physical property. Therefore, it is important to select the optimal laundry method depending on the filling material.

Nowadays, thermal comfort plays a prominent role in contemporary construction practices. Appropriate thermal insulation not only offers energy efficiency benefits in buildings but also enhances occupant well-being, comfort, and productivity. Therefore, a comprehensive understanding of the thermal properties of building materials is essential. This research aims to prepare and investigate a lightweight gypsum-based composite incorporating nano montmorillonite with advanced thermal insulation properties, considering both quality and cost-effectiveness while ensuring environmental compatibility.

This study adopts a laboratory experimental approach. A gypsum sample (without additives) and seven samples of gypsum combined with varying percentages of sodium and calcium montmorillonite nanoclays undergo extensive testing and analysis. Subsequently, the properties of these samples are compared.

The results indicate that adding montmorillonite nanoclays to gypsum composites reduces the density of the tested samples and increases their porosity. Moreover, the thermal conductivity coefficient decreases in these samples, significantly improving the thermal insulation properties of the lightweight gypsum plaster. This improvement is more pronounced in samples containing sodium montmorillonite nanoclay compared to calcium-based samples. Additionally, the investigations reveal that compressive strength decreases with the addition of montmorillonite to the samples.

In this research, laboratory experiments were conducted to investigate the physical and mechanical properties of gypsum plaster with varying percentages of sodium and calcium montmorillonite nanoclays. The studied properties include density, porosity, thermal conductivity coefficient, and compressive strength. Additionally, stress-strain diagrams, elastic modulus, and initial and secondary critical stresses were analyzed for each specimen.

This article aims to investigate a selected number of liquid hydrogen storage tank parameters in a turboelectric distributed propulsion concept.

In this research study, tank structure, tank geometry, tank materials and additional physical phenomenon such as hydrogen boil-off and permeation are considered. A parametric analysis of different insulation foams is also performed throughout the design process of a lightweight liquid hydrogen storage tank.

Based on the mass of boil-off and foam weight, phenolic foam exhibited better characteristics amongst the five foam insulation materials considered in this particular study.

Liquid hydrogen occupies 4.2 times the volume of jet fuel for the same amount of energy. This suggests that a notable tank size is expected. Nonetheless, as jet fuel weighs 2.9 times more than liquid hydrogen for the same amount of energy, this reduced weight aspect partly compensates for the increased tank size.

In this article, potential insulation materials for liquid hydrogen storage tanks are highlighted and compared utilizing a presented methodology.

This paper investigates thermal mass performance (TMP) in hot climates. The impact of using precast concrete (PC) as a core envelope with different insulation materials has been studied. The aim is to find the effect of building mass with different weights on indoor energy consumption, specifically cooling load in hot climates.

This research adopted a case study and simulation methods to find out the efficiency of different mass performances in hot and humid climate conditions. Different scenarios of light, moderate and heavyweight mass using PC have been developed and simulated. The impact of these scenarios on indoor cooling load has been investigated using the integrated environment solution-virtual environment (IES-VE) software.

The results showed that adopting a moderate weight mass of two PC sheets and a cavity layer in between can reduce indoor air temperature by 1.17 °C; however, this type of mass may increase the cooling demand. On the other hand, it has been proven that adopting a heavyweight mass for building envelopes and increasing the insulation material has a significant impact on reducing the cooling load. Using a PC Sandwich panel and increasing the insulation material layers for external walls and thickness by 50 mm will reduce the cooling load by 15.8%. Therefore, the heavyweight mass is more efficient compared to lightweight and moderate mass in hot, humid climate areas such as the UAE, in spite of the positive indoor TMP that can be provided by the lightweight mass in reducing the indoor air temperature in the summer season.

This research contributes to the thermal mass concept as one of these strategies that have recently been adopted to optimize the thermal performance of buildings and developments. Efficient TMP can have a massive impact on reducing energy consumption. However, less work has investigated TMP in hot and humid climate conditions. Furthermore, the impact of the PC on indoor thermal performance within hot climate areas has not been studied yet. The findings of this study on TMP in the summer season can be generated in all hot climate zones, and investigating the TMP in other seasons can be extended in future studies.

The environmental performance of several flat roof systems with different materials and insulation thicknesses is compared using life cycle assessment (LCA), with the aim to determine the roofing materials with the highest environmental performance. The paper aims to discuss these issues.

The calculations were carried out for an existing apartment block with a 300 m² flat roof. Five insulation materials with three different heat resistances each, five types of waterproof layers, three covering layers, and a green roof are assessed using LCA. Foreground data including maintenance are obtained from roofing companies, and background data are taken from Ecoinvent. ReCiPe is used as impact method. Energy losses through the roof are calculated using the energy software EPA-W.

Improving the insulation from 2.5 to 5 m²K/W leads to reductions of the damage scores from about 10 to 40 per cent. Polyisocyanurate and expanded polystyrene were found to have the lowest environmental damage, although the differences are small. Regarding the other layers, PVC mechanically fixed, ethylene propylene diene monomer (EPDM) mechanically fixed, EPDM glued and PVC with gravel ballast were found to have the lowest environmental damage of the materials assessed.

The outcomes of this study will aid building owners and construction and maintenance companies to choose renovation options for flat roofs with the lowest impact on the environment.

A smart choice of materials for a roofing system, with enough consideration of other aspects such as practical applicability, can thus significantly improve the environmental performance of the roof of a building.

Thermal insulation is important to achieve energy efficiency in a buildings’ lifespan while maintaining comfort. Traditionally, the majority of insulation in buildings is man-made petroleum based products with limited or no-end life usage. However, from an environmental and economic sustainability perspective, they are not sustainable as natural resources are finite and in danger of run-out. Furthermore, they are also highly influenced by the increasing price and the ongoing scarcity of fossil fuel oils. The paper aims to discuss these issues.

This paper introduces soap based insulation from recycled materials as a sustainable alternative to petroleum counterparts. The methodology is lab based experimentation and iterative tests. The phased based research process for the incremental development of the soap based thermal insulation is explained.

Findings reveal that soap based insulation can be one possible way forward in the quest for natural and sustainable thermal insulation from recycled products to preserve and conserve the sustainable environment.

Thus, the paper provides a unique environmentally friendly approach as an alternative to those existing petroleum counterparts for thermal insulation in buildings.

The purpose of this paper is to describe and discuss initial work to assess the moisture buffering performance of selected bio-insulations in lofts that suffer from excessive moisture following refurbishment.

These conditions were then reproduced in a physical lab-based experiment such that the comparative performance of the bio-insulations and stone wool could be measured.

It was found that the bio-insulations could remove over 60 per cent of the moisture in the loft air, and therefore reduce the risk of condensation and its severity.

The initial work reported here is indicative of the buffering potential of bio-insulations but further work is required to better quantify this performance. There is a need to further examine lofts with moisture problems and to produce reliable testing methods and protocols to be used when retrofitting loft insulation.

Installers and specifiers of loft insulation should ensure that insulation is installed correctly, as with the drive to increase loft insulation levels the risks of damaging the building fabric through condensation are increasing.

Excessive moisture can damage the building fabric and create health problems. Using insulations that perform well across a range of performance criteria tend to favour bio-insulations, which have a far less harmful impact on the environment than do typical fossil-fuel based insulations.

The paper presents preliminary findings that support arguments for specifying bio-insulations.

The purpose of this paper is to deal with performance verification of thermal insulation fillings that are used for outer clothes into cold environments. Thermal properties of filling materials (down and three sophisticated fillings) were tested under condition approaching real weather conditions in Middle Europe.

In the paper, modern method of thermal resistance Rct measurement, by Sweating Guarded-Hotplate system, was compared with method of Technical University of Liberec (TUL method). The TUL method shows good results and it is applicable even at ambient temperatures below zero, which fully corresponds to real application of the insulation filling.

Evaluation of fibre battings were carried out even at temperatures below the freezing point, which is important for simulation of actual application of these filling structures. The highest thermal resistance of goose down confirm that natural materials have their irreplaceable position, especially in application into clothes for extreme conditions.

There does not include effect of the humidity change on thermal insulation properties. It will be subject of further research of authors.

The investigation of thermal insulation properties were carried out under conditions approaching real application of tested materials, namely, at low ambient temperature.