Published: March 3, 2016


Fresh, outside air is introduced into commercial buildings in order to improve indoor air quality, diluting smells and chemicals in the conditioned space. Outside air can also be used for cooling, especially in temperate climates. In most U.S. commercial buildings, ventilation air and cooling is supplied by mechanical means. Prior to the 20th century, however, we relied solely on natural means for ventilating our buildings and maintaining cool indoor comfort levels during the summer.

The growing concern with building energy use, the rise of the green building movement and the goal of achieving net zero energy buildings has renewed interest in using natural ventilation strategies as a means of saving energy and improving indoor air quality. Natural ventilation relies on non-mechanical means to provide supplemental cooling when outdoor conditions are favorable as well as enough outdoor air to partially meet ventilation air requirements. In its simplest form it involves opening windows to bring outside air into the building. More sophisticated strategies involve siting and shaping the building to take advantage of the prevailing wind direction, employing controls that open and close windows based on outdoor conditions, as well as controls linking heating and cooling operation to the position of the windows.

Borgeson, Sam, 2008. Occupant Control of Windows: Accounting for Human Behavior in Building Simulation. Center for the Built Environment, University of California, Berkeley, CA.

Carbon Trust, 2012. A natural choice: lessons learned from low carbon buildings with natural ventilation, The Carbon Trust.

CIBSE, 2005. Natural ventilation in non-domestic buildings: CIBSE Applications Manual AM10, The Chartered Institution of Building Services Engineers, London, England.

Comité Européen de Normalisation (CEN) Standard EN 15251–2007: Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics.

Melton, Paula, 2014. Natural Ventilation: The Nine Biggest Obstacles and How Project Teams Are Beating Them, Environmental Building News, 23:8.