|Make-Up Air Systems
Building exhaust systems take out large volume of air from the building space. If this air is not replaced at the same rate that it is expelled, the building will experience a negative pressure (the air pressure outside the building is greater than the air pressure inside the building).
Some of the most common indicators of a negative pressure problem include the suction pressure that makes exterior doors difficult to open, exhaust fans that don't work properly, drafts around doors and windows, poor indoor air quality, and infiltration of outdoor air. These problems are more pronounced during the cold season when windows are kept closed, reducing the natural pressure-balancing effect.
A make-up air system replaces the air that is expelled by a building's exhaust system, maintaining the proper balance between inside and outside air pressures while also providing many other benefits:
supplies conditioned replacement air that can be heated, cooled, humidified or dehumidified