Studying the Properties of Particulate Insulating Materials on Natural Basis

Abstract

Recently, materials based on secondary raw materials have been the focus of attention of building companies and end users as well. The reason for this are mainly the low material costs, easy manufacture and application in building structures. Despite the lower cost compared to existing insulation materials, strict requirements are put on these thermal insulation materials. In response to the constantly increasing need for insulation materials and given the general requirement of sustainability in the use of natural resources, the Faculty of Civil Engineering in Brno has for many years been engaged in the development of insulation materials made from natural fibres of agricultural origin. These materials show great promise in civil engineering. They have a low carbon footprint and low primary energy input. Experimental testing conducted in the past has revealed that the properties of these materials are comparable to those of the synthetic insulations available on the market. However, in terms of thermal insulation properties, the natural-fibre materials have different hygrothermal behaviour, which is due to the different structure of the insulations as well as the low value of thermal conductivity of the natural fibres (compared with e.g. glass or mineral fibres). The paper deals with the development of particulate insulation based on natural fibers, their behavior under different conditions and mainly with the examination of the thermal properties depending on moisture and bulk density. The paper also presents the results of research in the dependency of thermal insulation, acoustic and mechanical properties of the experimentally manufactured insulations on their bulk density.Recently, materials based on secondary raw materials have been the focus of attention of building companies and end users as well. The reason for this are mainly the low material costs, easy manufacture and application in building structures. Despite the lower cost compared to existing insulation materials, strict requirements are put on these thermal insulation materials. In response to the constantly increasing need for insulation materials and given the general requirement of sustainability in the use of natural resources, the Faculty of Civil Engineering in Brno has for many years been engaged in the development of insulation materials made from natural fibres of agricultural origin. These materials show great promise in civil engineering. They have a low carbon footprint and low primary energy input. Experimental testing conducted in the past has revealed that the properties of these materials are comparable to those of the synthetic insulations available on the market. However, in terms of thermal insulation properties, the natural-fibre materials have different hygrothermal behaviour, which is due to the different structure of the insulations as well as the low value of thermal conductivity of the natural fibres (compared with e.g. glass or mineral fibres). The paper deals with the development of particulate insulation based on natural fibers, their behavior under different conditions and mainly with the examination of the thermal properties depending on moisture and bulk density. The paper also presents the results of research in the dependency of thermal insulation, acoustic and mechanical properties of the experimentally manufactured insulations on their bulk density.