The best choice of energy efficient envelope from variety of available materials is still the challenge. Therefore, the attempt of thermal performance multi-criteria evaluation of some building materials of natural origin for energy-efficient envelopes is conducted in present paper. Such types of walls from natural energy-efficient materials are considered in comparison assessment: hempcrete, adobe, strawbale panel, earthbag, cordwood, SIP (plywood+ecofiber), hempcrete+straw and energy efficient block. The influence of thermal inertia time, internal areal heat capacity, as well dimensionless index of thermal inertia D, the total thermal resistance of the walls Rtot-value, mass of the wall assembly and its cost have been taken into consideration as important influence factors. The multi-criteria numerical assessment of envelope’s energy efficiency potential was performed by two popular methods – Analytic Hierarchy Process (AHP) as the subjective weighting method and Grey Relation Analysis (GRA) as the objective weighting method. Both of methods allow to arrange the alternatives and could be applied as decision support tools in decision making (DM) process of choosing the best alternative in terms of multi-criteria assessment. For more objective analysis, by taking into account the variety of physical and physical-mechanical parameters of the wall assembly material, the concept of generalized index of the envelope energy efficiency potential is proposed. Conducted research has shown that the best envelope type in terms of of generalized index of energy efficiency potential has the hempcrete wall and hemcrete+straw wall, almost three times smaller has the wall of the earthbags. The walls from adobe, cordwood and strawbale panels have practically the equal value of generalized index of energy efficiency potential. It could be observed that AHP method shown more inhomogeneous results, than GRA. The possible reason for that is the difference in evaluation attitude in techniques - AHP is considered as the subjective method with pairwise comparison matrixes, while GRA is objective method of comparison.
According to the results of the analysis of research which is dedicated to the development of scientific and methodological basis and practical experience of the organization and management of the technological process, which is aimed to increase the energy efficiency of the thermal insulation shell, the organizational and technological factors of the improvement implementation of building envelopes were identified. It was noted that stimulating the active development of organizational and technological measures to improve the performance of building envelopes’ energy efficiency involves conducting further scientific research to find ways by creating an optimal indoor microclimate. It is expedient to identify the regularities of factors optimization’s methodological basis according to the proposed algorithm of multi-criteria analysis of their influence on the building envelopes’ energy efficiency. To formalize hierarchically the factors affecting the building envelopes’ energy efficiency, it is proposed to classify them according to such parameters as the natural and climatic requirements for the microclimate of the premises according to the building’s purpose, the structural features of the building façades, the physical and mechanical properties of heat-insulating materials, the ecological and economic characteristics of the heat-insulating of building envelopes.
The current state of research on monitoring and expert-analytical assessment of the reliability of the thermal insulation envelope of buildings is analyzed. It was established that the reliability of the thermal insulation shell is determined by organizational and technological factors that affect the probability of thermal failure of the enclosing structures. A structural diagram of the concept of monitoring is proposed for the purpose of developing mechanisms for ensuring the reliability of the thermal insulation envelope of buildings. The structural scheme of the concept of monitoring the reliability of the thermal insulation shell of buildings assumes that the components of the target monitoring program are technical diagnostics based on the results of experimental thermal imaging survey, analysis of the risks of thermal failure of enclosing structures and the development of an expert analytical assessment of the reliability of the thermal insulation shell of buildings.
According to the analysis of domestic and foreign literature sources, it is noted that reducing energy consumption to create an optimal microclimate of buildings involves reducing heat loss through external enclosing structures. Construction of new buildings and thermal modernization of existing ones is carried out with the use of different properties of thermal insulation materials, passport data of manufacturers on their characteristics need to be clarified in determining the energy efficiency of buildings. Mineral wool was selected for experimental studies of thermal insulation material used to improve the thermal insulation shell. The energy efficiency of mineral wool was studied using an installation with a climate chamber with a homogeneous heat flux over the cross-sectional area of the sample. To register the change in the amount of heat flux, thermocouples were used, which are located at different points of the climate chamber with a sample of mineral wool. Data on the change in temperature during the observation period before the stabilization of the heat flux was determined by the automatic registration unit. The change in time of the temperature regime at different points of the mineral wool sample is obtained. The thermal conductivity, which characterizes the efficiency of the thermal insulation material made of mineral wool, was calculated according to the known Fourier formula for stationary thermal regime from the values of the temperature difference in the characteristic cross sections of the sample. The discrepancy between the values of thermal conductivity of the investigated sample and the passport data of thermal conductivity of mineral wool provided by its manufacturer is revealed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.