We show an approach to estimate turbulence intensity of turbulent jet boundary layer. This approach uses geometric and kinematic analysis of simplified scheme of its macrostructure. It is a continuation of researches performed by professor of Heat Gas Supply and Ventilation Department of Kyiv National University of Construction and Architecture Andrei Tkachuk. The obtained value of maximal turbulence intensity is coincides with known experimental data. This approach allows estimating of turbulence parameters of ventilation currents for energy efficiency optimization of air exchange organization.