The process of supplying air to, or removing air from, a house, most often with a fan.

 

Above definition Copyright © The Home Ventilating Institute. Some content originally appeared in John Bower's book, Understanding Ventilation, published in 1995 by The Healthy House Institute.

 

From HHI:

 

Another word for “airing the place out,” ventilation is one of the top three ways to improve indoor air quality.

 

Ventilation is the movement of outdoor air into a building or space through open windows, doors, air moving systems or by infiltration.

 

This is important since indoor air is usually more polluted than outdoor air.

Ventilation is one of the three best ways to enhance or protect indoor air quality:

• The first is to capture contaminants at the source before they become airborne.
  
  
• The second is ventilation.
  
  
• The third is cleaning the air.

Reference: U.S. Environmental Protection Agency