The single greatest energy conservation opportunity available today in most homes is sealing leaks in the heating duct system. Because heating contractors in the past were not generally aware of the importance of airtight integrity in the duct system, they employed shortcuts like using joist cavities or stair towers as a duct, and did not take great care in making duct connections. And unfortunately duct tape used to seal the joints, which seems to work well for just about every other purpose, does not last well on ducts.

The furnace blower is the most powerful piece of equipment in a home, and generates very high pressures inside the duct system. In a leaky system this can lead to the following problems:

• Wasted energy: Conditioned air leaks into unconditioned space, or outside air is drawn into the system.
• Poor air quality: Leaks in return air ducts draw pollutants from the crawl space, attic or garage into the home. These include dust, mold spores, insulation fibers, organic vapors and other contaminants.
• Air wars: Strong interior pressures caused by duct leakage can cause combustion appliances to backdraft and discoloration to appear on carpet and other materials.

Atmosphere, Inc. uses state-of-the-art pressurization equipment called the “Duct Blaster” to measure duct leakage and identify problem areas. We systematically go through the duct system, reconnecting and supporting where needed, replacing damaged parts and sealing all accessible leaky joints. We also seal leaks at the furnace cabinet and plenums. A final pressure test documents the improvement and confirms that remaining duct leakage is minimal.

We will generally recommend having the system cleaned, particularly if significant leaks were sealed in the return ducts. With a tight duct system you can expect to find less dust in the home, improved indoor air quality, reduced drafts and much lower energy bills.