Install tight-fitting, insulating window shades on windows that feel drafty after weatherizing.
Install additional attic insulation at right angles to the previous layer. You don't have to use the same type of insulation - it's fine to use batts or blankets over loose-fill, or vice versa. Upgrading from three inches to 12 inches can cut heating costs by 20 percent, and cooling costs by 10 percent.
To save on heating and cooling costs, close your curtains and shades at night; open them during the day.
The lower the U-value, the better the insulation. In colder climates, a U-value of 0.35 or below is recommended. These windows have at least double glazing and low-e coating.
Water heating typically accounts for 14 percent of your utility bill. Repairing leaky faucets, insulating the water heater tank and hot water pipes, and installing low-flow faucets and shower heads can result in significant additional savings.
By simply caulking, sealing, and weatherstripping around all your windows, outside doors, or where plumbing, ducting, and electrical wiring penetrate exterior walls, floors or ceilings, you can save 10 to 25 percent of your heating bill.
Look for dirty spots in your insulation, which often indicate holes where air leaks into and out of your house. You can seal the holes by stapling sheets of plastic over the holes and caulking the edges of the plastic.
To stop airflow between walls and floors, Install foam gaskets on all outlets and switches, and use child safety plugs backed with punch-outs to keep the cold air from coming through the sockets. Remember, be careful whenever working around electricity.
Attic doors are a major source of heat loss in many homes. To stop airflow, weatherstrip the edges and insulate the back side of the attic door. Fold-down stairs can be covered with a lightweight box made of rigid insulation.
Bathroom fan fixtures can poke into the attic insulation and create a pathway for air leaks. Caulk around them from below with high-temperature flexible caulk.