Check your roof insulation - How much roof insulation do you have? Hot air rises, so your home's most likely area to release heat is the roof. The most efficient way to stop that loss is by ceiling and roof insulation with an R-value of approximately 40. R-value is the ability of any material to resist the passage of heat.

Fill the gaps - Heated air can also escape from gaps that develop where building materials meet. Look for signs where materials have pulled apart and caulk or seal the gaps. Check areas where exterior siding meets windows and doors, along the roof and foundation lines, around chimneys and where pipes protrude through walls or roofs.

Inspect your heating system - Consider replacing an older or inefficient heating unit with a gas furnace or a heat pump with a mid - to high-efficiency rating. If you currently have an efficient system, inspect and clean it now. Make sure your filters are clean. Change inexpensive throwaway filters monthly.

Grab a sweater - Keep your thermostat at 20°C or 68°F during the winter. Consider replacing and existing thermostat with a programmable model that can turn down the heat while you sleep or when you are not at home.

Check your windows - Be sure you have good windows and doors. If you don't, this should be a high priority. Also, look for any cracks around glass, sashes and window frames that could be leaking air. Apply adhesive foam weather-strips to top and bottom window rails or nail felt weather stripping where window sashes and frames make contact. If you live in a home built since 1991, you are likely to have double or even triple-paned windows and low-emissivity (Low-E) glass. Both these products increase your energy efficiency and can lower your energy bills.

Clean gutters and downspouts - Even though gutters and downspouts don't affect your energy bills directly, they should be checked twice a year. Gutters and downspouts are traps for falling leaves and pine needles, and squirrels can use them as pantries for storing winter food. Be sure to clean gutters thoroughly, and pay special attention to elbows and bends in the downspouts. Keep hangers fastened securely. Plug any holes and cracks. Repaint rusting components inside and out with paint specially formulated for that application.

Preventive maintenance will help you protect your investment in your home.