Rats are more likely to seek shelter near homes during the colder months. The National Pest Management Association (NPMA) reports that 45% of annual rodent infestations occur during fall and winter, making the period before temperatures drop an important time to check a property for vulnerabilities.
Norway rats and roof rats may move toward warmer areas when the weather turns cold. Potential hiding places include insulation beneath a subfloor, roofs, garages and lofts. Indoors, they may shelter behind refrigerators, dishwashers and dryers, or near furnaces and hot-water pipes. Heavy rain can also drive them inside.
Rats can enter through very small openings, squeezing through gaps roughly the size of a quarter. To reduce access, inspect walls, doors, windows and other exterior openings. Plastic, rubber and standard vinyl caulk may be chewed through, while copper mesh can be used to fill holes and then covered with silicone caulk.
Outdoor maintenance can also help. Keep lawns trimmed and cut back foliage near the house, particularly climbing plants such as English ivy around walls and windows. Overgrown vegetation can provide cover and routes toward potential entry points.
Trash containers should be kept in good condition, since cracked or damaged bins and exposed garbage can attract rats. Bird feeders may also draw rodents, especially during winter. The source recommends waiting until spring or using huskless seed together with a squirrel guard if feeding birds continues.
Garages deserve particular attention when they contain food or pet food. These supplies should be stored in airtight, rat-resistant metal containers. Food kept inside the home should likewise be protected in airtight plastic or glass containers.
Rodent-proof door sweeps can help close small gaps beneath external doors, including doors connecting the home and garage. Checking these areas before cold or wet weather arrives can help prevent rats from finding a warm route indoors.
Sources: Tom's Guide.