Why Ventilate

Mechanical Ventilation


As defined by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), ventilation is “the process of supplying outdoor air to or removing indoor air from a dwelling by natural or mechanical means”.

Pollutants, Source Control, and the Need to Ventilate

Numerous pollutants exist within buildings and homes that can negatively impact indoor air quality and occupant health. Some of the most common pollutants are the building and finishing materials used in construction. Many builders are doing a good job of limiting the use of products that contain volatile organic compounds (VOCs). VOC’s are carbon-based compounds that have been used in the construction or chemical composition of many building material products like compressed wood cabinets, paints, glues, adhesives, and carpets. These VOC’s can evaporate and “off gas” as part of the natural part of aging and curing in new homes.

The Benefits Of Mechanical Ventilation Are:

How Ventilation Systems Work

A variety of mechanical ventilation systems are available to select from, based on local climate and the home’s heating and cooling system. In addition to one of the primary systems described below, “spot” ventilation fans should also be provided for kitchens and baths to remove the concentrated moisture and odors that can occur in these rooms. The typical systems and recommended climates are described below:

Mechanical Ventilation Types

There are three types of whole house ventilation strategies: exhaust only, supply only, and balanced.

Essentials of Mechanical Ventilation for Homeowners/Residents

With the increasing tightness of homes, mechanical ventilation is a necessary feature for building design to ensure acceptable indoor air quality and maintain occupant comfort. However, mechanical ventilation is affected by many factors that determine its efficiency and effectiveness, including building tightness, duct systems, and outside air conditions. Understanding these factors is beneficial for homeowners and residential occupants to maintain a healthy and energy efficient space.

All of the above factors impact effective ventilation.