Air and Duct Sealing
Why Air Sealing is Important
Leaky ductwork is a serious source of energy waste in most older homes. The Florida Solar Energy Center has found that ducts in Florida homes leak up to 30% of their heated and cooled air. Since most duct are in unconditioned attics or crawlspaces, that energy is lost directly to the outside. Worse, the return ducts try to make up for this lost air by sucking hot, humid air in from the outside. If the air comes directly though cracks in the building shell it brings dust, spores and other contaminants affecting your air quality. If it comes from leaks in a return duct in the attic it will bring in extremely hot humid air. In the cooling season, 20% duct leakage can lead to a 50% increase in cooling bills as your AC unit works harder to remove the extra moisture from the air.
How We Test
While an experienced home energy analyst will know where to look for the most significant leaks, a diagnostic test using a blower door (basically a large fan sealed to one doorway) is the most objective way to pinpoint and actually measure the amount of leakiness. We use state of the art blower door equipment and computer software to precisely lower the pressure inside the house a small amount and then note the leaks using a smoke puffer to see and our hands to feel where the air is leaking into the house. The test and software let us determine the total leakage area and how much time and effort are justified to correct it.If the blower door test gives an indication of duct leakage problems, a separate duct leakage test can be done. The “duct blaster”, a small fan similar to a miniature blower door is attached to the duct system and all the other registers are sealed off. Pressurizing the system lets us test the amount of leakage in the ducts.
Correcting Leakage Problems
Correcting air leakage has some of the best cost payback of any home energy efficiency measure, often 1-3 years. Some jobs, such as weatherstripping doors are good DIY projects. However, the significant hidden leaks in attics, crawlspaces and ducts are often best left to professionals with the right materials, tools and techniques to be safe and efficient. Green Energy Options can either perform these energy sealing measures or refer them to a company we trust. Either way, we will retest your air leakage and combustion appliances after such air sealing has been done. This assures that the work has been done properly. More importantly, it confirms that changing your home's airtightness has not created any unsafe conditions for the combustion appliances. This is part of the “house as a system” approach.Click here to view our prices.