Using of supplement based on calcium hydrosilicates as structuring supplement in dry mixes lime is proposed. It shows the impact of supplement synthesis mode on the structure formation of calcareous compositions. The efficiency of the using of modifying supplements of amorphous silica, such as diatomite, in the synthesis is shown. It has been established that in supplement of calcium hydrosilicates synthesized with diatomite a greater amount of calcium hydrosilicates, belonging to low-basic ones, are contained. X-ray analysis of samples based on synthesized supplements is presented. A high activity of synthesized calcium hydrosilicates had been established. It has been established that the injection of supplements of hydrosilicates accelerates the gain of mechanical strength. It is shown that the injection of supplements of hydrosilicates accelerates the increase of water resistance and frost resistance of coatings. The operational properties of coatings based on the developed dry mix with the addition of calcium hydrosilicates synthesized with diatomite are presented.