Ventilation refers to the exchange of indoor and outdoor air. Without proper ventilation you could be trapping in harmful pollutants, such as carbon monoxide and moisture that can harm your home and the occupants.
You have certainly heard the phrase from a carpenter – “you don’t want to build too tight.” This was a concept that many people knew and understood in the construction industry for years. We then realized our electric bills were going through the roof. The old way of building was to let a house ‘breath‘ or be ventilated through gaps, cracks, and joints in your thermal envelope (walls and roof). Now that we are building tight efficient homes that don’t ‘leak’ or ‘breath’ we need to bring in fresh air for the purpose of better indoor air quality and dehumidification.