Yes, I have the title right. I meant “duck” (as to move, to avoid). I know the title doesn’t seem to make sense because we do want to duck in the attic, don’t we? If you have ever hit your head in the attic, it was an accident, you were not thinking or paying attention, and it hurt for a long time. And when it happens, we proceed to take great pains never to do it again.
Unfortunately, as home building professionals, we have been ducking our energy responsibility in the attic, avoiding a major energy loss issue. When I said don’t “duck” in the attic, I really meant “be responsible”. I meant don’t duck on this issue because it will hurt for years. Look at the facts from the ENERGY STAR web site. This is painful.
In a typical house… about 20 percent of the air that moves through the duct system is lost due to leaks, holes, and poorly connected ducts. The result is higher utility bills and difficulty keeping the house comfortable, no matter how the thermostat is set.
Twenty percent is a lot. Look at the five negatives of “return air ducts” in the attic:
- Your conditioned air travels through the attic deep freeze or solar oven, stealing your energy dollars.
- Return air “sucks in” this “bad” attic air through these leaks, making your system work harder.
- Return air leaks in the attic cause your house to be dry in the winter and too humid in the summer.
- These leaks bring in pollen, fiberglass fibers, and other outside allergenic issues.
- Leaks cause the system to fail in delivering the correct air balance to the needed rooms, creating hot or cold rooms.
In the three Habitat houses that are almost finished, only one has duct in the attic. Software analysis shows that it is the least energy efficient of the three, yet it is the same size with the same features except for the attic duct. In about a year, the utility bill will prove this correct and I will let you know. But, this is not new science; we do not have to wait.
As a designer I often suggest that we don’t “duct” in the attic. That way we don’t “duck” our responsibility as professionals who claim to be building energy efficient houses. There are a number of solutions around this, and many HBA builders are utilizing these methods. Ducts in unconditioned attics and crawl spaces are the single biggest energy losers today. But a slight change in the way we think and design a house’s HVAC system could save thousands of energy dollars. Now that’s just ducky!
Jim D. Baker, B & G Drafting—HERS Rater and NAHB Verifier with this project.
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In January 2011, the HBA of Greater Springfield announced it would partner with Habitat for Humanity of Springfield to build the first two homes in Habitat’s new Builders Circle development. The homes will be certified to the National Green Building Standard and their construction will serve as a demonstration of flexible and affordable methods by which construction professionals can build green in a residential setting.
Jim Baker (B&G Drafting) is a Certified Green Professional (CGP), a HERS Rater, and a certified NAHB Green Building Verifier. He also helped design these and other green-built homes throughout the area. This Builders Circle Project Blog helps keep HBA industry professionals and curious consumers up to date on the latest green building features being incorporated into the project. The blog also provides updates on the project’s latest progress and upcoming needs. Those who would like to help with the project are encouraged to leave their comments at the end of blog posts, or on the project’s facebook page, to offer your assistance.
Jim D. Baker, B and G Drafting – HERS Rater and NAHB Verifier on this project.