air duct sealing
The Facts
The average homes ductwork leaks out 10-30 percent of the air through joints, seams and holes instead of making it out the designed areas or registers.
Location
If your ductwork is located inside the home envelope this is not really an issue.
The Facts
The seams where the ductwork is pieced together is not airtight but often times, there are even larger gaps resulting in even more lost air and lower system efficiency.