The paper is focused on the effect of chemical additives, namely plasticizing agents on the heat emission in the context of cement hydration. The authors find to what extent each additive affects this process for CEM II 32.5H and CEM I 42.5H. They come to the conclusion that this additive decreases the maximum temperature of the mixture heating. In laboratory conditions the standard consistency for all compositions is chosen in accordance with GOST 310.3-76. The research results are obtained with the help of an adiabatic calorimeter. The area to determine the amount of heat generated over a defined period is calculated.