Home Energy Audit in Middletown, DE home.
Challenge
You might be surprised to know many "energy efficient" homes, even those recently constructed, often have many flaws that will, sooner or later, result in unnecessary expenses due to energy loss. These flaws are not easily spotted by a person untrained in residential home energy. But an energy auditor like Declan Hindsley, trained and certified by BPI (Building Performance Institute) has the tools and knows exactly where to look to find these flaws.
Declan spotted a number of potential issues in this Middletown, DE home, constructed just two years ago in 2021. This particular home was particularly challenging due to its multiple attic sections, each with its unique configuration and associated problems.
One of the first red flags was the HVAC ductwork running through the harsh environment of an unconditioned attic where temperatures can range from 30 degrees Fahrenheit or below in the winter and often exceeds 150 degrees on hot summer days when the sun is beating down on the black shingled roof. If the ductwork leaks either now or later when the fittings weaken and begin to fail, precious conditioned air spews out into the attic and is swept away out into the big blue sky, along with it your energy dollars. It remains unclear from the pictures available, but locating HVAC return ducts in the narrow space between a cathedral ceiling and a roof deck is often the source of problems. These areas are difficult to insulate properly and result in heat transfer - made even worse by the moving of air through the channels.
Another common problem in this attic are sections of poorly insulated walls with unconditioned attic space on one side and conditioned living space on the other.
And finally, though for the most part, the contractor who built this home did a good job of air sealing the attic floor, Declan spotted numerous places where large gaps at the tops of wall sections that should have been sealed with expanding foam were neglected, allowing conditioned air from the living spaces below to be drawn up into the attic through the hollow wall cavities.
Solution
The solutions to these problems aren't easy, since the flaws were covered over with cellulose insulation. You know what your parents always said, "Do it right the first time." It would have been much better and far less expensive to have addressed these issues during the original construction. As for the issues in the cathedral ceiling, there may be very little that can be done now. But the attics are a different story. Dr. Energy Saver recommends sealing all the gaps and air leaks in the attic floor with Zyp expandable foam. But in order to do this you must start with a perfectly clean attic floor. This means the old insulation has to be removed. Proper dams and walkways are built to contain the new TruSoft™ insulation. And wherever possible it is best to bury any exposed ductwork in the cellulose, since the existing duct insulation is usually only of modest value, in this case only about R7.
As for the duct work, taped seams and mastic typically used by HVAC contractors has a limited ability to air seal the ductwork. The ductwork found in the average American home loses 40% of the conditioned air before it even reaches the rooms where it is needed. Lawson Home Services employs an amazing process known as AeroSeal™. Invented by a research scientist at the University of California, AeroSeal is unique - it seals the ductwork from the inside. This brilliant solution is far superior to the tape and mastic used by most HVAC contractors.
