The brunt of weather abuse is taken by your roof in the form of snow and ice. To check your roof you are going to need a ladder, a pair of binoculars, or a trusted roofing expert. If access is at all unsafe or difficult, or if getting up on a roof just isn't your thing, contact a local roofing professional and they'll take a look for you. If you have a sloped roof, look for shingles that are cracked, curled, loose, damaged, or missing. Once located, repair or replace them. If you have a flat roof, clean off leaves and branches, and cut back overhanging tree limbs. Watch for low spots where water will pond. Look for bulges, worn spots, or split seams on the membrane. Regardless of your roof type, pay attention to the junctions between the roof and the chimneys, pipes, and walls. Often you'll find that metal flashings need to be re-secured or re-caulked. Again, if it's damaged, fix it as soon as possible.
If you can access the roof safely, take a look at the chimney. Brick chimneys may have loose or missing mortar and loose or damaged bricks, and should have a screen to keep animals out. Metal chimneys should be free from rust and should have a rain cap.
Eavestroughs and Downspouts
While at roof level, be sure to clean and re-secure the eavestroughs. We can't overemphasize the importance of free-flowing, leak-free eavestroughs and downspouts. If your eavestroughs can't control the rain or melting snow, the ground will get saturated. If the ground is soaked around your house, there is a much higher risk of a leaky basement. You should also follow the downspouts to ground level to check where they dump the water. Above-grade downspouts should be well secured and discharge water at least six feet away from the nearest wall, or at a point where run-off will be carried away from the house. It is recommended that downspouts that disappear into the ground be disconnected and redirected to discharge above ground well away from the house. This is an easy and surprisingly effective basement leakage cure.
Once you are off the roof and on the ground, take a walk around your house to check how the ground directs the flow of water. All surfaces next to the walls should slope down away from the house to direct water away from the foundation. Poor grading is a common and preventable cause of basement leakage. This is exponentially more important on warm winter days when melting snow or rain runs quickly across the surface of frozen ground. If the grading is poor, water will accumulate against the foundation of the home and will often cause basement flooding. Now is the time to grab a shovel and re-slope the grass, or call a paving contractor or handy person to correct a poorly-sloping driveway or walkway.
During your exterior walkabout, check the windows and doors for any wood in need of paint and any joints that need re-caulking. Look for rot at window sills and any horizontal wood surfaces where water may collect. Tapping on painted wood surfaces with the handle of the screwdriver for example, is a good way to identify soft or rotted wood. Also check the caulking at pipes, vents, and other wall penetrations. Seal these areas before it gets too cold - this can also help reduce your energy bills.
Your heating system is the heart of your home and your best friend in the winter. The most important fall activity is to schedule a heating system maintenance call. This applies to both newer and older furnaces and boilers. The technician will clean the burners and fan or pump, lubricate the moving parts, change the filter and check the operation of the important safety devices. Heat exchangers on high efficiency furnaces may need to be flushed. If you choose to have this service done later in the heating season, you can still start the winter season off right by replacing or cleaning the furnace air filter. If you have a humidifier, you should clean it as well.
If you live in a new house, odds are your windows and doors are well sealed. Old windows and doors (and unfortunately even some newer ones), may need sealing to keep heat in and cold out. One approach would be to replace them - but that can get costly. Luckily, great improvements can be made with simple weatherstripping kits available at any hardware store.
The list above includes the most important fall tune-up steps.
Other great winterizing ideas include:
Turning off the water supply to your outside hose faucet, unless it is a frost-free type.
Cleaning the grilles and registers on the heating system - especially the cold air return.
Cleaning and lubricating exhaust fans in kitchens and bathrooms.
Cleaning out the clothes dryer vent and cover.
If you have electric baseboard heaters, vacuum the dust off the fins, and make sure drapes and curtains are several inches above their hot surfaces.