Sealing air leaks
Test your home for air tightness and save 10 percent on heating bills
On a windy day, hold a lit incense stick next to your windows, doors,electrical boxes, plumbing fixtures, electrical outlets, ceiling fixtures, attichatches, and other locations where there is a possible air path to the outside.If the smoke stream travels horizontally, you have located an air leak that mayneed caulking, sealing, or weather-stripping. -- Department of Energy
