Durability Assessment of ETICS: Comparative Evaluation of Different Insulating Materials

The External Thermal Insulation Composite System (ETICS) is a common cladding technology that is widely used thanks to its well-known advantages. Despite previous studies dealing with ETICS durability in real-building case studies or involving accelerated ageing tests in climatic chambers, little progress has been made in the knowledge of the long-term durability of the system. In order to realize optimized maintenance plans for this component, the durability of the whole system, and of the most-used insulating materials for the ETICS (i.e., cork, polyurethane, rock wool, glass wool, grey EPS, and fiberfill wood), has been investigated. Based on previous experiments on ageing cycles, different climatic chambers were used to accelerate performance decay by simulating natural outdoor exposure in order to assess different physical and thermal characteristics (thermal transmittance, decrement factor, time shift, water absorption, thermal resistance, and conductivity). Recorded trends show that materials with lower thermal conductivity exhibit lower performance decay, and vice versa. The durability of the ETICS with different insulating materials (as the only variable in the different samples) was evaluated in order to quantify service life and then correctly plan maintenance interventions. Life-cycle assessment must take into account service life and durability for each material of the system. A higher durability of insulating materials allows for the execution of less maintenance interventions, with the loss of less performance over time. This study shows the physical and thermal behavior of the ETICS during its service life, comparing the differences induced by the most-used insulating materials. As a result of accelerated ageing cycles, the analyzed ETICS reveals a low grade of decay and measured performances show little degradation; for thermal conductivity, differences between the measured and the declared conductivities by technical datasheet were observed.

How Reliable is the Thermal Conductivity of Biobased Building Insulating Materials Measured with Hot Disk Device?

Thermal conductivity is of high importance for insulating materials since it strongly influences the thermal performance of the building. Generally, it is recommended to measure this property with steady-state methods like guarded hot plate (GHP) or heat flow meter (HFM). These methods are reliable, but steady-state condition can take a long time to be reached. Therefore, transient methods were developed to speed-up the measurements. For instance, the hot disk transient plane source method is a widely used standard technique (ISO 22007-2) for measuring thermal conductivity of various materials. In the last 20 years, this technique has been applied also to bio-based insulating materials. However, overestimated thermal conductivity (compared to steady state method) are frequently measured. More generally, such differences are also observed for low thermal conductivity materials. The aim of this work is to evaluate the influence of numerous factors to explain the origin of these differences. The factors include the experimental setting parameters, the measurement analysis parameter or even the discrepancies between the theoretical model and the real experimental set-up. The analysis is performed for a light-earth biobased concrete made of raw earth and hemp shiv. Recommendations are proposed in conclusion.

Breakdown Properties of Cables with Different Inorganic, Insulating Nanomaterials

The insulation performance of cable insulating materials can be optimised via matrix modification. Typically, low-density polyethylene (LDPE) is used as the matrix, and a certain proportion of nanoparticles are added to this matrix. To explore the effects of nanoparticles with different forms on the structural interface and crystal morphology of the material, nano-MMT and nano-ZnO were added to LDPE, and comparative experiments were carried out. Based on microscopic test results, material insulation performance changes before and after optimisation were observed. Then, simulation cable models with different insulating materials were developed. Based on the simulated electrical measurements, the thermal breakdown performance of the different insulating materials was tested. According to infrared stereo vision detection results, anomalous temperature points in the cables can be located accurately. Finally, based on macroscopic test results, we verified whether the inorganic, insulating nanomaterials meet the requirements for high-voltage transmission.

Thermal insulating materials on liquid glass binder

The article discusses the possibility of creating new inorganic heat-insulating materials based on liquid glass binder and mineral fillers. Within the framework of the article, the influence of various additives such as sawdust, chalk, coal and graphite on the physical and technical properties of an inorganic heat-insulating material is considered. The authors of the article proposed the compositions and conditions for obtaining materials that meet the regulatory requirements for materials and products for building thermal insulation

Insulation of historic buildings and case study simulation

The article deals with the historic buildings and their insulation. It is generally known that classical thermal insulation of walls from the outside is not permissible due to the cultural value of historic facades. Compared to external insulation solutions, the implementation of internal insulation is more technically complex and faces several risks. In the article is devoted the chapter which deals with the aim of the application of internal insulation in historic buildings. There are mentioned risks associated with the application of internal insulation, which are related to the thermal-humidity behaviour of the structure. One chapter is devoted to faults that may occur after the application of internal insulation. These disorders have a building-physical character and also affect the hygienic criteria of the building. The larger chapter deals with insulating materials suitable for the purposes of interior insulation of historic buildings. The results of a case study from Dublin and Košice are also presented, where the thermal-humidity behaviour of selected thermal insulation materials was investigated. The results of moisture content and surface temperature before and after application of insulating materials are compared.

Methodology for assessing the degree of moisture ingress into the insulation of traction electric motors of diesel locomotives

Objective: To develop a method for assessing the degree of moisture absorption by the traction electric motor (TEM) insulation. Methods: Based on the analysis of one-dimensional diffusion of liquid into the insulating material of the TEM windings, it has been shown that cracks increase its saturation with liquid. The proposed analytical solution for anisotropic diffusion of liquid into a cracked insulating material has been investigated. Results: An analytical model has been developed that describes the ideal moisture absorption according to the Fick's law, and it has been shown that it is suitable for calculating the diffusion of moisture into the insulating materials of the TEM windings. Practical importance: Further research should be aimed at obtaining material properties in a moisture-controlled environment