What is necessary for natural ventilation to be effective?

Natural ventilation relies on the movement of air through openings such as windows, doors, and vents in a building to facilitate airflow. For natural ventilation to be effective, it depends heavily on environmental factors, specifically wind and other natural air movements. These forces help create pressure differentials that promote the flow of fresh air into a space while allowing stale air to escape. Wind can enhance the effectiveness of natural ventilation systems by actively pushing air through openings, thereby improving indoor air quality and reducing the accumulation of smoke, heat, or harmful gases.

Establishing a consistent supply of clean air is important as a principle of good ventilation, but it does not inherently define how natural ventilation operates. Engine-powered extraction methods and the strategic placing of ductwork refer to mechanical ventilation systems, which utilize powered equipment for air movement rather than relying on natural phenomena like wind.