Make-Up Air

Definition

Air brought into a building from outdoors through the ventilation system that has not been previously circulated through the system.

Purpose

Make-up air ensures adequate ventilation by replacing air that is exhausted from the building, maintaining indoor air quality, and preventing negative pressure. It is crucial in systems that expel large volumes of air, such as kitchens, laboratories, and industrial facilities.

Examples of Use

• Commercial kitchens: Providing fresh air to replace the air exhausted by kitchen hoods.
• Laboratories: Ensuring a safe working environment by replacing contaminated air with fresh air.
• Industrial plants: Maintaining air balance and quality in environments with high exhaust rates.

Related Terms

• Ventilation: The process of supplying fresh air and removing stale air from an indoor space.
• Exhaust Air: Air that is removed from a building through ventilation systems.
• Air Handling Unit (AHU): A device used to regulate and circulate air as part of a heating, ventilating, and air-conditioning system.

Notes

• Make-up air systems must be properly designed to balance the exhaust and intake air to avoid pressure imbalances.
• The quality of make-up air should be monitored to ensure it does not introduce contaminants.
• Energy recovery systems can be integrated to pre-condition make-up air, improving energy efficiency.