Which system requires makeup air due to interference from exhaust fans?

Ventilation systems require makeup air because they actively exhaust indoor air to maintain indoor air quality and reduce humidity. When exhaust fans are running, they create a negative pressure within a building, which can lead to a deficiency of air. To compensate for this loss and maintain proper air balance, additional air, called makeup air, needs to be introduced from outside.

This is essential to ensure that the system operates efficiently and safely, as inadequate air supply can cause issues such as backdrafting of combustion appliances, difficulty in maintaining desired temperature settings, and increased energy consumption due to inefficient system operation. Properly managing makeup air helps sustain a healthy indoor environment by ensuring a continuous flow of fresh air, which is particularly critical in spaces with high levels of exhaust.