Why Verdun Has One of the Worst Rodent Problems in Montreal

Published April 7, 2026 · Extermination DMP

If you live in Verdun, you already know. The scratching in the walls. The droppings behind the stove. The neighbor who just had their third exterminator visit this year.

Verdun has a rodent problem. Not a small one. Our pest pressure data consistently scores Verdun at 97-100 for rodent activity — among the highest on the entire island of Montreal.

But it is not because Verdun is dirty or poorly maintained. It is because of five structural factors that no amount of cleaning will fix.

Factor 1: The Building Stock

Verdun's residential buildings are predominantly pre-1960 construction. Walk down any residential street and you will see row after row of brick triplexes and duplexes built in the 1940s and 1950s.

These buildings were constructed with methods that are structurally sound but not rodent-proof. The foundations are concrete block or poured concrete — materials that crack with decades of freeze-thaw cycles. The original plumbing and electrical penetrations were never sealed to modern pest exclusion standards. The mortar between bricks deteriorates over time.

Every spring, new cracks appear. Every fall, mice find them.

Factor 2: Rental Density

Verdun has one of the highest percentages of rental housing on the island — approximately 64% of dwellings are rented. High rental density creates pest challenges for several reasons:

• Delayed maintenance. In rental housing, landlords may not invest in preventive exclusion work (sealing cracks and holes) until a tenant complains. By then, the mice are already inside.
• Tenant turnover. Frequent tenant changes mean pest issues are not consistently reported or tracked. A mouse problem that one tenant tolerated becomes the next tenant's crisis.
• Multi-unit transmission. In triplexes and small apartment buildings, mice travel freely between units through shared wall cavities, plumbing chases, and electrical conduits. Treating one unit without treating the building is futile.

Factor 3: Construction Activity

Verdun has been undergoing significant development — new condos along the waterfront, road reconstruction, infrastructure upgrades. Every excavation displaces rodent colonies that have lived underground for years.

Where do those displaced rodents go? Into the nearest available structure. A construction project on one block can trigger mouse invasions in buildings three blocks away.

Our data shows a direct correlation: zones with active construction permits consistently score higher for rodent activity than zones without.

Factor 4: Waste Infrastructure

Verdun's dense residential areas generate significant waste in a compact footprint. Back alleys lined with garbage bins, recycling containers, and compost bags create a continuous food source for rodents.

Any disruption to regular waste collection — holidays, storms, strikes — immediately increases rodent activity. The food source that was contained in bins for 24 hours is now sitting in torn bags for 48-72 hours.

Factor 5: Geographic Position

Verdun sits along the St. Lawrence River and is bordered by the Lachine Canal to the north. These waterways create moisture corridors that support rodent populations. The canal infrastructure — old retaining walls, abandoned industrial structures, overgrown embankments — provides harborage for large rat populations that feed into the residential neighborhoods.

What Verdun Residents Can Do

You cannot change the building stock, the density, or the geography. But you can make your individual dwelling less hospitable:

For Homeowners

• Annual foundation inspection every September. Seal every crack larger than 6mm.
• Steel wool and caulk around all pipe penetrations under sinks and behind appliances.
• Door sweeps on all exterior doors and the garage door.
• Monthly bait station program from October through March if you are in a high-activity area.
• Trim vegetation away from the foundation — 30cm clearance minimum.

For Tenants

• Seal gaps in your unit around pipes (under sinks, behind toilet, around stove gas line).
• Install door sweeps on your apartment door if you can see daylight underneath.
• Report immediately to your landlord in writing at the first sign of mice.
• Request building-wide treatment — insist that the landlord treat the basement and common areas, not just your unit.
• Keep food sealed — all dry goods in glass or heavy plastic containers.

For Landlords

• Invest in exclusion — it costs $500-$2,000 per building and prevents $3,000-$10,000 in annual treatment costs.
• Standing pest control contract — monthly monitoring and treatment for the building, not reactive individual unit calls.
• Treat the building, not the complaint — when one tenant reports mice, inspect and treat all units. The mice are not limited to one apartment.

Frequently Asked Questions

Will Verdun's rodent problem ever get better?

Is it safe to raise children in Verdun because of the rodent issue?