Rats and Mice: How They Get In, and How to Close the Door

Every autumn, the same story plays out across East Hampton. The nights turn cold, the summer crowd heads home, and the rodents that spent the warm months in the woods and dunes start looking for a warmer address. A house that sat quiet for a week — or a basement that stays damp all year — starts to look very inviting to a rat or a mouse.

If you've heard scratching behind a wall at night, found droppings in the back of a pantry drawer, or spotted a greasy rub mark along a baseboard, you probably have company. The good news is that rodent problems follow a logic you can see and understand. Once you know how they got in and what keeps them there, you can shut the operation down.

Which rodent are you dealing with?

Two species cause most of the trouble in local homes: the common house mouse and the Norway rat. Telling them apart matters, because their habits differ.

House mice

Small, curious and relentless. An adult mouse weighs about half an ounce and can squeeze through a gap the width of a pencil — roughly a quarter inch. Droppings are small, dark and pointed at both ends, like grains of black rice. Mice explore constantly, so they turn up in kitchens, pantries and drawers where people actually notice them.

Norway rats

Bigger, warier and mostly ground-level. Norway rats burrow — under sheds, along foundations, beneath woodpiles and dense ground cover — and they prefer to travel the same protected routes night after night. Their droppings are larger, blunt-ended, and usually found in basements, crawl spaces and along foundation walls. A rat that avoids your trap for a week isn't smarter than you; it's just suspicious of anything new in its path.

How they get in

Walk around your house slowly, at their eye level, and the entry points start to announce themselves. In East Hampton's older shingle homes, the usual suspects are:

• Gaps where pipes, cables and utility lines pass through the foundation or siding
• Cellar windows and bulkhead doors with warped frames or rotten sills
• The space under a garage or exterior door with a worn sweep
• Cracks in stone or block foundations, especially where mortar has crumbled
• Roofline gaps — where a soffit meets a wall, or around a chimney flashing
• Vents: dryer vents, attic vents and crawl-space vents without proper screening

A mouse only needs one of these. A house built in the 1950s, settled and shifted by seventy winters, usually offers several.

A mouse needs a gap the width of a pencil. Most older homes offer a choice of doors.

Why they stay

Entry is only half the equation. Rodents remain where three things line up: warmth, food and shelter. Birdseed stored in a garage bag, pet food in an open bin, a trash can with a loose lid, an unused basement corner full of cardboard boxes — each one is an amenity. Winterization habits matter too. A house closed up for the season with a full pantry and no visitors is, from a mouse's perspective, a well-stocked hotel with no staff. It's the same arithmetic that sustains cockroaches in a damp basement: take away the comfort, and the pest leaves.

What works: exclusion first

Traps remove the rodents you have. Exclusion decides whether you get more. Do both, but start with the structure:

1. Seal the small gaps. Pack holes with copper or steel mesh, then seal over with caulk or mortar. Expanding foam alone is a snack, not a barrier — rodents chew through it. The mesh is what stops them.
2. Fit door sweeps. Any exterior door with daylight under it needs a proper sweep or threshold seal.
3. Screen the vents. Hardware cloth over crawl-space and attic vents, a pest-proof cap on the dryer vent.
4. Fix the food. Birdseed, pet food and pantry goods move into hard-sided containers with tight lids. Garbage goes out in cans that actually close.
5. Clear the shelter. Firewood stacked away from the house and off the ground. Dense ivy and ground cover trimmed back from the foundation. Storage in bins, not cardboard.
6. Then trap. Snap traps, set perpendicular to walls along known runways, baited lightly. Check them daily. Skip the poison indoors — a rodent that dies inside a wall is a two-week problem of a different kind.

When to call a professional

A couple of mice in a garage in October is a reasonable DIY project. Some situations aren't: rats established in burrows around the foundation, activity inside walls and ceilings across multiple rooms, any rodent issue in a home that also operates as a rental, or droppings and damage that keep reappearing after you've sealed and trapped. At that point the job is less about catching animals and more about reading the building — where they're nesting, how they're moving, what's sustaining them.

That's the work a licensed exterminator does with an inspection first and a treatment plan built around your property. If you're at that stage, look into rat and mice control in East Hampton, NY from a local team that starts with a thorough inspection rather than a generic spray.

The bottom line

Rodents aren't a verdict on your housekeeping; they're a fact of living where woodland meets coastline. The homes that stay free of them share one habit: someone walks the perimeter once a season, notices the new gap, and fixes it before anything moves in. Make that walk part of your autumn routine, and most years the scratching you hear will be the wind.