Building industry as an important branch of the economy of each country consumes significant amounts of energy and emits greenhouse gases into the environment (CO2 ). These negative effects which affect on the environment have a contribution to make many of the restrictions recorded in the documents of sustainable development in the construction industry. The most significant are: environmentally friendly building products, energy efficiency of buildings, organized management of construction wastes including demolition materials. However, in relation to a building and its surroundings can be distinguished: reduction of impurities emissions resulting from the combustion of the heating facility, reduction of the energy demand for heating, possibility of disposal of waste and effluents. These considerations leads to the exploration and initiation of new construction materials and technologies, and in the final stage for the implementation of low-energy and passive buildings. This paper presents the results of preliminary studies of new composite material based on foam lime mortar, packed with natural flax fibers and additives and admixtures. The paper presents the physico- mechanical characteristics of the composite (strength parameters, absorption, coefficient of thermal conductivity, etc.) of different composition mix output. It is expected that the composite will be applied in the implementation of low-energy and passive building as parts fulfilling the structural and insulation function. The proposed material solution from natural ingredients meets the requirements of sustainable development in the construction industry. Studies are carried out under a cross-border grant from the Technical University in Brest and the material as the original solution is submitted to the Polish Patent Office.
