1.    Seal cracks around windows, doors, siding, utility pipes, and other openings. Use weather stripping or a good quality silicone or silicone-latex caulk. Larger gaps can be sealed with urethane foam, glass wool or stainless steel wool, etc.

2.    Install tight-fitting door sweeps or thresholds at all exterior entry doors. Worn door sweeps and gaps in door jams can be discovered by turning off outdoor and indoor lights at night and remaining indoors while someone shines a flashlight beneath and around doors to reveal gaps.

3.    Inspect and replace worn garage door seals; rubber seals work better than vinyl seals in cold weather.

4.    Repair or replace damaged or loose-fitting door and window screens.