How to Prevent Heat Loss and Gain in Your Home - Today's Homeowner

Up to 40% of the heat loss or gain in a home is due to leaks in the thermal envelope surrounding the living space. To save energy, make sure the attic has plenty of insulation, and fill any cracks or gaps around windows, doors, plumbing pipes, and HVAC lines. Installing foam gaskets behind switch and outlet covers is another good way to reduce air infiltration in your home.

from Home Improvement 1 http://bit.ly/2G1shnu