Winter can take its toll on a house. And when the weather turns foul, many homeowners tend to stay indoors and defer maintenance.

To help protect one of people's most valuable assets, Consumer Reports recently identified some potential problems and suggested ways to fix them:

• Dirty air conditioners. Disconnect electric power to the air conditioner's outdoor condenser and clear it of leaves and debris with a vent brush, power blower, garden hose or vacuum cleaner's brush attachment. Be careful not to bend any exposed cooling fins.

In yards with lots of trees and plants, wrap fiberglass mesh around the condenser coil to capture pollen and leaves and replace as needed. Don't allow debris to block airflow.

Check vacuum grilles and registers inside the home to ensure good airflow and change furnace filters.

CR recommends 3M's Filtrete, $20, and Ultra Allergen Reduction 1250, $16, furnace filters.

• Hazardous decks. Look for water stains where the deck ties to the house. Ongoing water leakage can lead to wood decay, weakening the deck structure and the house. If there are any doubts about structural integrity, call a pro.

Rid decks of moss and mold. Pressure washers are effective, but when there's wood damage such as raised fibers, increase the distance between the spray nozzle and the decking. CR recommends electric pressure washers. They're quieter and easier to store and transport than gas-powered models. The Campbell Hausfeld PW1345, $90, was tops for speed and convenience.

Cabot's opaque decking stain (1480) was the best overall in CR's latest tests. Wolman semitransparent DuraStain (18146) lets the wood grain show and required less prep work but won't last as long.

• Foundation fissures. Hairline cracks in foundation walls might be the result of concrete curing or minor settling and aren't automatically cause for alarm. Mark them with tape and if they worsen after a few months, call a structural engineer. If they're stable, fill them with an epoxy injection system.

Check that the ground around the foundation slopes away from the house (about 1 inch per foot). Look for pellet-shaped droppings or shed wings from termites. Clear the area of leaves to prevent rodents from nesting. Fill holes in siding and foundation walls with expandable foam.

• Leaky roof. Leaks typically occur around inadequately flashed chimneys, skylights and other openings. They're easiest to spot in the attic; inspect the rafters for water stains. Patching leaks is best left to professionals. While they're up on the roof, have them clean leaves from roof valleys.

Examine the siding under roof eaves and ceilings in the rooms below for water or discoloration, indications that ice dams may have created leaks along the roof edge. Inspect the roof for cracked, curled or missing shingles. Asphalt shingles typically last 20 years.

CR recommends thick laminated shingles. They did best overall in tests, although some less expensive, three-tab shingles also performed well.

• Clogged gutters. Clear gutters of debris and check for corrosion, joint separation and loose fasteners. Flush out downspouts and unclog leader pipes. Leaders should extend at least 5 feet to direct water away from the foundation.

CR recommends Type 1A ladders for added safety. Never go beyond the labeled highest step. For projects above 17 feet, use a conventional extension ladder. The $120 Cosco 2061A 6-foot stepladder was top-rated in CR's recent tests.

• Faulty garage-door openers. To check that the door is balanced, release it into the manual mode and lift it by hand. The door should lift easily and smoothly, and it should stay open on its own about 3 feet off the ground. If it doesn't, its overhead spring needs to be counterbalanced by a garage-door technician.

Next, set the opener's reversing force as low as possible. Place a 2x4 board on the ground under the door, wide side down. The door should pop back up when it hits the 2x4. If it doesn't, call the pro. Test photoelectric eyes by holding the 2x4 between them. The door should reverse direction.