A controller for dynamically balancing air pressure in a building including at least a first room, includes a receiver, a processor, and a transmitter. The receiver is configured to receive an outdoor air pressure measured by an outdoor pressure sensor, and to receive a room air pressure measured by a room pressure sensor. The processor is configured to calculate a pressure set point based on the outdoor air pressure, to determine whether the room air pressure deviates from the pressure set point by a predefined threshold, and to generate instructions for a heating ventilation and air conditioning (HVAC) unit to adjust the room air pressure to the first pressure set point. The transmitter is configured to transmit the instructions to the HVAC unit. A system and a process for dynamically balancing air pressure in a building including at least a first room are also provided.