Why Mice Enter Calgary Homes in the Fall — And How to Keep Them Out

Martin’s Pest Control | Calgary, Airdrie & Surrounding Areas

As temperatures begin to drop across Calgary and southern Alberta, mice start looking for warm, sheltered places to spend the winter. Unfortunately, your home, garage, or commercial building may provide exactly what they're looking for.

At Martin’s Pest Control, we understand how frustrating a mouse infestation can be. Whether you're hearing scratching noises in the walls or discovering droppings in your kitchen, taking action early can help prevent a small rodent problem from becoming a much larger one.

Why Do Mice Enter Homes in the Fall?

Mice are active throughout the year, but colder weather often increases their need to find protected shelter.

Calgary's freezing temperatures, snowfall, and changing weather conditions make residential and commercial buildings attractive places for rodents.

Mice enter buildings primarily in search of three things:

• Warmth: Heated buildings provide protection from Alberta's harsh winters.

• Food: Pantry items, pet food, birdseed, and improperly stored garbage can attract rodents.

• Shelter: Wall cavities, basements, attics, garages, and storage areas offer protected nesting locations.

One of the biggest challenges is that mice can squeeze through openings approximately 6 mm (¼ inch) wide.

That means even a small gap around a pipe, foundation, or exterior door may be enough to allow a mouse inside.

Five Signs You May Have Mice in Your Home

Mouse infestations aren't always immediately obvious. In many cases, homeowners discover evidence of rodents long before seeing a live mouse.

Here are five common warning signs.

1. Mouse Droppings

Small, dark droppings resembling grains of rice are often found inside kitchen cupboards, underneath sinks, or along walls.

2. Scratching Noises

Mice are generally most active at night. Scratching, scurrying, or rustling sounds inside walls and ceilings may indicate rodent activity.

3. Chewed Food Packaging

Mice have strong front teeth that continually grow. They frequently gnaw through cardboard, plastic packaging, and other materials to access food.

4. Unpleasant Odours

A persistent musky smell may indicate an established rodent infestation, particularly in enclosed areas.

5. Nesting Materials

Shredded paper, insulation, fabric, and other soft materials may indicate that mice are building nests inside your home.

Are Mice Dangerous?

Although mice may appear harmless, an infestation can create serious concerns for homeowners and businesses.

Mice can contaminate food and surfaces with urine and droppings. They may also damage insulation, stored belongings, and electrical wiring.

Rodents can carry disease-causing organisms, making proper cleanup and prevention important.

If you discover mouse droppings, avoid sweeping or vacuuming them while dry. Follow appropriate disinfecting procedures to reduce the risk of airborne contamination.

How to Prevent Mice From Entering Your Home

Preventing mice from entering a building is one of the most effective ways to reduce future infestations.

Seal exterior openings. Inspect your foundation, siding, utility penetrations, and exterior doors. Seal gaps using appropriate rodent-resistant materials.

Install door sweeps. Exterior doors, including garage access doors, should close tightly without leaving gaps underneath.

Store food properly. Keep dry goods, pet food, and birdseed in sealed, rodent-resistant containers.

Reduce outdoor clutter. Firewood, debris, and vegetation close to your foundation can provide shelter for rodents.

Inspect garages and storage areas. Attached garages are common entry points, particularly when overhead doors do not seal properly.

Remember that prevention is an ongoing process. Buildings naturally develop gaps and openings as materials age and settle.

Why Mouse Traps Alone May Not Solve the Problem

Many homeowners attempt to control mice using traps purchased from hardware stores.

Although trapping can reduce rodent activity, it may not address the underlying cause of the infestation.

If mice continue entering through foundation gaps, poorly sealed doors, or utility openings, new rodents can replace those removed.

Effective mouse control involves identifying entry points, evaluating rodent activity, implementing appropriate control measures, and recommending ways to prevent future infestations.

Professional Mouse Control in Calgary and Airdrie

At Martin’s Pest Control, we provide pest management services for residential and commercial properties throughout Calgary, Airdrie, and surrounding communities.

Our approach focuses on identifying pest activity, addressing existing infestations, and helping property owners understand how to reduce future problems.

Whether you're dealing with mice in your basement, garage, warehouse, or commercial property, professional pest control can help you regain control of the situation.

Don't Wait Until a Small Mouse Problem Becomes a Major Infestation

Mice reproduce quickly, and an infestation can become more difficult to manage when left untreated.

If you've discovered droppings, heard scratching noises, or noticed other signs of rodent activity, consider having the situation professionally assessed.

Contact Martin’s Pest Control today.

📞 403-460-7213

Serving Calgary, Airdrie, and surrounding Alberta communities.

Visit our website to learn more about our pest control services or to request assistance.