Sealing your attic is another one of ... These areas usually have open stud cavities leading directly into the attic that are huge sources of air leaks. Locate the main plumbing stack, furnace ...
Blown-in insulation is excellent at trapping heat; however, it won't stop airflow into your attic space from gaps and cracks.
Before adding new insulation—whether you're removing old materials or not—take the time to seal air leaks in your attic. Roof leaks and gaps around light fixtures, plumbing vents, and ductwork ...