Home Performance Analysis - Duct Leakage Test
If your home is heated or cooled with a forced air system, your heating and cooling costs are affected by how airtight your ducts are. Independent studies throughout the United States have shown that duct air leaks can increase heating costs by 15% to 30%. In many cases, sealing these air leaks will save more energy than any other home improvement.
What are ducts?
Most people notice the registers where warm air comes into their homes, but most of the ducts that deliver this air are hidden from view in attics, crawl spaces, between floors and in walls. If you have a basement or a furnace in the garage you may be able to see part of this system. There are two main parts of the duct system:
1. The "supply" ducts deliver warm air from the outside and cool air from the air conditioner. The air in these ducts is the most valuable in your home because you are spending money to heat or cool it. If you feel air blowing out of a vent, it's connected to a supply duct.
2. The "return" ducts carry air from inside your home and return it to the furnace, heat pump or air conditioner. Return ducts are usually larger than supply ducts, and you should not feel air blowing out of them, but you might be able to feel the air being pulled in.
A few things to know about ducts
Sealing leaky ducts does more than save energy. Sealing ducts can make your home more comfortable, improve air quality and reduce the risk of back drafting furnaces, water heaters and wood burning devices.
• Newer homes have leaky ducts, too. In fact, they're just as likely to have very leaky ducts as older homes.
• It's not unusual to find supply ducts that are completely disconnected. Disconnected supply ducts dump heat into crawl spaces, attics or other places where heat is wasted, so it's important to reconnect them.
• Leaks in return ducts pull air into the system from wherever the leak is. When the leak is in a garage, basement, crawl space or attic, the return air can be polluted by pollutants like car exhaust, pesticides, dust, mold and moisture.
How can I tell if my ducts are leaky?
Pressure testing your ducts using a duct blaster test will tell you how leaky your ducts are. A duct blaster is a fan that pressurizes your ducts to a standard test pressure and measures how much air flow it takes to reach that pressure. The more flow through the fan, the leakier the ducts. To run this test, your Home Performance contractor will temporarily seal the vents that are usually open to your home. This test is usually done at the same time the blower door test is operating. Your contractor will normally test your home for air leaks and duct leaks during the same visit.
How should I prepare for a duct leakage test?
In order to prepare for this test, your Home Performance contractor will need access to all of your heating or cooling vents, whether they are in floors, walls or ceilings. The Home Performance contractor will also need to access your furnace, heat pump and central air conditioner. The blower door will also be operating during this test, so you will need to follow the preparation guidelines for the blower test as well.
Sealing ducts and safety
All Home Performance contractors who seal ducts need to know if combustion devices such as furnaces, fireplaces, water heaters, and wood stoves are still operating properly. The combustion safety tests use a "micro manometer," which measures whether combustion devices will still vent gases out of your home after your ducts are sealed.
What are the next steps after the Home Performance tests?
After thoroughly testing and evaluating your home, the Home Performance contractor will put the test information into a computer program that will print a report to help you decide what to do next. The report will identify which improvements will save the most on your energy costs and make recommendations to improve comfort, indoor air quality, and safe operation of combustion devices like furnaces, fireplaces, and water heaters.
If you are looking for an Oregon duct sealing contractor, please call us today at (503) 640-1700 or complete our online request form.