In modern conditions durability and reliability of buildings are demanded more and more. According to it the special attention starts to be given to the danger of biological degradation of materials and constructions. Microorganisms are capable to occupy the surfaces of all tested kinds of widely used binding agents. However, the specific and quantitative compositions of microorganisms are various under identical service conditions. Having compared the quantity of kinds and types of the fungi developing on the samples of binders, it is possible to evaluate the efficiency of application of those or other building composites and to choose the most suitable materials for corresponding service conditions. It was experimentally shown that composites on a basis of alkaline glass binding agents possess the raised stability in the biologically corrosive environment.