Posted February 5, 2026

As temperatures drop in New Haven County, CT, mice and rats actively look for warmth, food, and shelter.

Most rodent infestations begin outside the home, long before activity is noticed indoors.

This guide highlights the most common exterior rodent entry points and harborage areas found in homes throughout New Haven, North Haven, Wallingford, Hamden, Branford, and surrounding towns.

Most Common Rodent Entry Points Around Homes in New Haven County

Roofline, Vents & Chimneys

Rodents commonly enter through open or damaged roof vents, gaps around chimneys, and unsealed soffits or fascia. Cold weather increases activity at rooflines as rodents seek warmth.

Foundation & Siding Gaps

Cracks, holes, and gaps where siding meets the foundation are common entry points, especially in older homes throughout New Haven County. Even small openings can allow mice inside.

Garages & Entry Doors

Garages are one of the most common access points for rodents. Worn or missing garage door sweeps, gaps at door corners, and visible light under doors make entry easy.

Basements & Crawl Spaces

Broken or missing crawl space vent covers, utility penetrations, and poorly sealed basement windows provide direct access for rodents.

Exterior Harborage Areas

Rodents are attracted to exterior food and shelter sources such as firewood stacked near the home, bird feeders and spilled seed, uncovered trash cans, outdoor pet food, and dense vegetation along foundations.

Why Rodent Activity Increases During Winter in New Haven County

Cold Connecticut winters push rodents indoors quickly. Once inside, mice and rats can nest in walls, attics, and insulation, often going unnoticed until damage or noise appears.

Identifying and sealing entry points early can help reduce the risk of rodent activity and prevent costly damage during the colder months. If you’re unsure where rodents may be getting in or want a professional set of eyes on your home, a proper exterior inspection can make all the difference.

Serving homeowners throughout New Haven County and surrounding towns.

Call or message today to schedule an inspection or learn more.