How to Keep Mice Out of Your House – Simple DIY Tips

We love cabins because they’re so cozy. Unfortunately, that’s why mice like them too.

Once inside, mice can chew wires, spread disease and reproduce quickly. Ahead are some expert-approved tips from Dr. Nancy Troyano, a certified entomologist and Director of Operations, Education and Training at U.S. Pest Operations (Rentokil – Terminix), along with Ricky Young of Youngs Pest Control, to help you keep mice out of your house.

Why do mice enter homes and cabins?

“Mice are on a relentless search for food, warmth and shelter,” says Dr. Troyano. “Especially in the fall and winter, mice are trying to find a way inside. Mice and other rodents will scale walls, climb ladders, walk across wires and swim through sewers to get inside your home.”

Identifying and Sealing Entry Points for Mice

Mice can wriggle through gaps the size of a dime, so start by checking for openings that need to be sealed. Mice are likely to enter from:

• Holes where gas, water, electrical and data lines enter the house;
• Cracks between the wall, floorboards and baseboards;
• Cracks in the foundation;
• Openings around windows and doors;
• Improperly sealed sink and bathtub drains;
• House corners, specifically in gaps between J-channels and siding;
• Basements or crawl spaces;
• Dryer vents;
• Damaged roofing and soffits.

Screen and caulk

On larger gaps, dryer vents and soffits, use galvanized mesh wire or screen to block entry points. Use caulk as necessary to seal the edges of the screen. Caulk is also effective in blocking most small entry points.

Steel wool and foam

On harder-to-seal spaces, use tightly packed coarse-grade steel wool, which mice are unlikely to chew through. Expanding foam can also seal up entry holes. It works best when you first pack the hole with steel wool.

Expanding foam will also help keep out unwanted insects, spiders and cold air. But it isn’t smell-proof, so mice can still be lured inside by enticing scents. For best results, buy a mouse or pest-deterrent product. Here are a few tips for keeping mice out of your house.

Doors and windows

Install door sweeps on the bottom of doors, especially in older cabins where there’s more likely to be a gap. Also check the weather seals along the garage door bottom to make sure they’re still intact.

Mice can chew through some types of screens as well. “Use steel screens or other heavy-duty materials for window screening,” says Ricky Young of Youngs Pest Control. Galvanized metal screens are widely considered the most effective.

Here are a few tips for DIY cabin pest control.

Close the flue

If you have a fireplace, clear the flue of debris and then close it tightly for the season.

To tell if it’s fully closed, look up the chimney from inside for signs of light, or reach up and touch the damper. Check for a draft. If you don’t feel one, carefully light a rolled-up newspaper and put it inside the top of the fireplace. If the flue is still open, it will pull the smoke and flames upward.

Leave everything tidy

Inside, deep clean the kitchen and pantry, including the cabinets, before taking off for the season. Vacuum or sweep all the floors and remove all garbage. The fewer crumbs, the less enticing it is for mice to move indoors.

Outside, trim tree branches back from the house and avoid letting plants grow up the sides of your cabin. “Overgrown vegetation close to walls will offer shelter to mice and potential nesting sites,” says Troyano.

Also, keep bird feeders far from the house. When you leave for the season, take them down, clean and store them. Leave the grass short to reduce shelter and seeds for food. Move woodpiles away from the cabin. Keep bushes and other landscaping a few feet from the foundation; this also minimizes wildfire risk.

Store food in containers

If they can smell it, they’ll try to come in and eat it. Minimize smells by putting all food in plastic, metal or glass containers with tight-fitting lids. Mice are particularly fond of dry goods like pasta and crackers. Store food higher on shelves or in the refrigerator or stove.

“Or better yet, leave [the kitchen] empty during the winter,” says Young.

Use repellents for rodent-proofing your cabin

Certain scents help keep mice at bay. Put mothballs underneath the porch or hang them in mesh bags or stockings around the cabin.

A nontoxic alternative, peppermint oil, also irritates a mouse’s nasal passages. Spray a modest mixture of peppermint essential oil and water on possible entry points. Clove oil can be substituted for peppermint.

“Some people also try hanging dried herbs such as peppermint and eucalyptus near entry points to keep mice out,” says Young. “If it doesn’t help, at least your cabin will smell nice.”

Year-round maintenance tips for a mouse-free home

Mice don’t just enter during the winter. So while you’re hanging out at your cabin, get in the mouse prevention habit:

• Regularly clean up crumbs and food scraps from countertops and floors.
• Don’t leave pet food on the ground overnight.
• Keep doors closed, especially the garage door.
• Consider adopting a new cat friend or a mouse-chasing terrier.
• Set a humane trap or two to see if mice are around. Check traps regularly so mice don’t die of dehydration or starvation. If you do catch a mouse, release it as far from the cabin as possible—100 yards is fine, a mile even better.

Additional Mouse-Proofing Tips

Make friends with the neighbors

If you have neighbors who live near your cabin year-round, ask if they’ll check in on it from time to time and alert you if they see signs of mice. That way if a mouse gets in, you’ll know you need to take action before there’s a full-on infestation.

Set up a camera

If you don’t have neighbors, install a few security or wildlife cameras to alert you when there’s movement.

Tip: Not just any trail cam will work. Because mice are so fast and small, you’ll need higher-quality video or burst-photo capability. And place the camera where mice are likely to pass.

Set traps

Some people set up mouse traps while they’re away to catch rodents that elude the other safeguards. Young and Troyano recommend heavy-duty traditional spring traps, which are the most humane. If you find your mouse traps aren’t working, there are ways to enhance a standard trap. Avoid sticky traps, which can cause mice to chew off their feet or die slowly and inhumanely.

Note: There are also poison traps that make mice seek water, drawing them outdoors before they die. But remember: Introducing such poisons into the food chain can jeopardize healthy ecosystems.

FAQ

What smells do mice hate?

Certain plant-derived scents repel mice. Research on rodents’ response to certain smells indicates that plant secondary metabolites (PSMs) such as methyl nonyl ketone, black pepper oil and anthraquinone act as an effective and natural deterrent to mice.

How do you seal gaps to keep mice out?

According to the Centers for Disease Control and Prevention (CDC), the best course of action is to inspect your home’s interior and exterior for gaps and holes, especially around doors, windows, pipes and vents. Steel wool combined with caulking can seal small holes, while larger openings can be repaired or closed using lath screen, metal sheeting or cement. As a practice, ensure that all your doors and windows close tightly and that screens are intact. You can also use stainless steel wool, wire mesh or galvanized steel to block any structural gaps, as these materials are resistant to gnawing by rodents.

What are humane means of deterring mice infestations?

Keeping mice from your house humanely involves preventative measures and small lethal deterrents. Preventing food and water sources by keeping living quarters clean and food in sealed containers is one of the most successful methods. It’s also important to close off any potential entry points, including cracks, gaps or holes in walls as well as around pipes, to keep mice from getting inside the home. For mice that are already indoors, live traps allow you to capture and release the rodents outside, without killing them. You can also use natural repellents such as peppermint and eucalyptus essential oils around doors or other small openings or hiding places, as rodents generally do not like strong odors.

About the Experts

• Dr. Nancy Troyano is a board-certified entomologist and Director of Operations, Education and Training at Ehrlich Pest Control. As an expert in pest behavior with many years of experience, she offers science-informed advice on effective pest prevention methods.
• Ricky Young is a pest control professional at Youngs Pest Control, who specializes in providing hands-on, field-proven solutions for rodent and insect infestations in homes and seasonal properties.

Sources

• Centers for Disease Control and Prevention (CDC): “How to Seal Up to Prevent Rodents”
• USEPA: Do’s and Don’ts of Pest Control
• National Library of Medicine: “Like or dislike: Response of rodents to the odor of plant secondary metabolites”