When estimating the ventilation flow of an enclosed parking garage various factors come into play, such as its use, its geometry and its location. Current regulations describe generic solutions based on data that are sometimes obsolete. The aim of this work is to achieve greater efficiency in the ventilation systems of enclosed parking garages. To this end, an in-depth study has been carried out on the factors that influence the calculation of the ventilation flow. If the application is used in an urban parking garage a considerable reduction in ventilation flow is revealed compared to current standards. Also, an analysis has been conducted of the energy consumption as well as the amount of CO2 emitted into the atmosphere together with an economic study. The results of this research show that the proposed solution for the studied parking garage reduces energy consumption by 24.10%, leads to a fall in CO2 and represents a cost saving of 18.93% in the cost of the ventilation system and a saving of 6.35% in annual operating costs. (C) 2013 Elsevier Ltd. All rights reserved.