A mouse does not need a large opening to get inside, it can squeeze through a gap about the width of a pencil, so even a small crack around a pipe or door can become an entry point. Sealing these gaps, storing food securely, and removing outdoor shelter can help make your home less to a mice infestation. (cdc.gov)

If you have already seen mice or found droppings, sealing your home is an important prevention step but it may not resolve an active infestation on its own, especially if mice are nesting in a wall, attic, basement, or crawl space. This how to article will provide practical mice infestation tips for you and your home.

Mice Infestation Tip #1: Start with a careful inspection

To effectively identify a mice infestation check both inside and outside your home. Use a flashlight, and look for gaps, gnaw marks, droppings, or nesting material. Pay close attention to areas where pipes, wires, vents, and utility lines pass through walls or floors.

Inside, inspect:

• Under and behind kitchen and bathroom cabinets
• Around pipes beneath sinks and near water heaters or furnaces
• Behind refrigerators, stoves, washers, and dryers
• Along baseboards and where floors meet walls
• Around fireplaces, floor drains, and vents
• In basements, crawl spaces, closets, and attics

Outside, check around:

• Doors, windows, and garage doors
• The foundation and the area where it meets the ground
• Utility lines, cables, and plumbing
• Roof edges, eaves, soffits, and attic or crawl-space vents
• Siding, skirting, and exterior wall penetrations

A mouse can enter through an opening as small as about 1/4 inch so do not overlook narrow gaps.

Mice Infestation Tip #2: Choose the right materials to seal gaps

The best repair depends on the opening’s size and location. For small gaps, pack steel wool into the opening and secure it with caulk. For larger openings, use durable materials such as metal mesh, hardware cloth, sheet metal, or cement. Caulk or expanding foam alone may not hold up where mice can chew or push through, so use a sturdy barrier where needed.

Make sure vents still have proper airflow after you seal around them. Use a secure, rodent-resistant screen where a vent or opening needs to remain open, and avoid blocking equipment vents or other openings that serve a safety purpose.

Mice Infestation Tip #3: Check doors, windows, and the garage

Look for daylight beneath exterior doors and garage doors. If you see a gap, install or replace the door sweep or threshold so the door closes tightly. Repair damaged weather stripping and window screens, too.

Remember to check side doors, basement doors, and the door between the garage and house. A small gap at one of these locations can give mice an easy route indoors.

Mice Infestation Tip #4: Reduce food, water, and hiding places

Sealing entry points works best when your home and yard offer fewer reasons for mice to stay. Store pantry food, pet food, and animal feed in sturdy containers with tight-fitting lids. Clean crumbs and spills promptly, take out garbage regularly, and put away pet food and water bowls overnight.

Outside, use garbage cans with secure lids and clear away brush, clutter, and materials that can provide shelter. Keep firewood raised off the ground and away from the house, and trim vegetation near the foundation. These steps can reduce food and nesting opportunities around the home.

Mice Infestation Tip #5: What to do if you find mouse droppings

If you find droppings or nesting material, do not sweep or vacuum it dry. Wear rubber or plastic gloves, wet the material with an appropriate disinfectant, and follow the product label before wiping it up. The CDC advises against sweeping or vacuuming rodent waste because it can stir contaminated particles into the air.

If the signs are in a hard-to-reach area, or there is a large amount of waste, consider getting professional help rather than disturbing the material yourself. Environmental provides free estimates and free inspections for all mice infestation issues.

Mice Infestation Tip #6: Sealing the house may not be enough

A sealed home can help prevent new mice from entering, but it does not remove mice that are already inside. For this, rodent stations with active bait will need to be included in the treatment strategy. If you continue to hear scratching, find fresh droppings, or notice new gnaw marks after sealing visible gaps, there may be another entry point or an active infestation that needs attention from a professional pest control company.

Environmental Pest Control provides mice and rodent control in the Mid Atlantic. A professional inspection can help identify likely entry points and determine what steps may be needed to address ongoing activity.

Quick checklist for mouse-proofing your home

1. Inspect inside and outside for gaps about 1/4 inch or wider.
2. Check around pipes, wires, vents, doors, windows, and the foundation.
3. Use sturdy, suitable materials to close openings.
4. Repair door sweeps, weather stripping, and damaged screens.
5. Store food and pet food in sealed containers.
6. Remove outdoor clutter and shelter near the home.
7. Get help from a pest control company if mouse activity continues or signs are in inaccessible areas.