Mechanical Ventilation uses motorized fans and ductwork to actively supply and remove air from building spaces, maintaining controlled indoor air quality and thermal conditions independent of outdoor weather. This system provides reliable ventilation regardless of wind, temperature, or building configuration.
System Components
Mechanical ventilation systems include intake dampers, supply fans delivering 0.15-0.3 cfm per square foot of outdoor air, ductwork distribution, exhaust fans, and controls. The system may include filtration (MERV 8-13 filters), heating/cooling coils, humidification, and carbon monoxide/PM2.5 sensors. Energy recovery ventilators (ERVs) capture 50-80% of exhaust air energy to precondition incoming air.
Applications
Mechanical ventilation is required in sealed office buildings, hospitals, laboratories, food service facilities, and spaces where outdoor air quality is poor. Most commercial buildings operate 24/7 mechanical ventilation systems.
Energy Considerations
Mechanical ventilation typically consumes 5-15% of building HVAC energy. Efficiency improvements include variable air volume systems, demand-controlled ventilation reducing fan speeds during low occupancy, and energy recovery ventilation equipment. Proper commissioning ensures systems deliver required outdoor air without excessive fan energy.