Rodent Control: How to Control and Prevent Mice and Rats in Canadian Homes

TL;DR

• Rodent control is usually a plan, not a single product: sanitation, sealing entry points, trapping, and baiting only as a supplement (UC IPM).
• Seal gaps with materials rodents generally can't chew, like steel wool and metal mesh. Mice fit through cracks as small as a dime, rats through a quarter-sized hole (Health Canada).
• Store dry food and pet food in metal or glass containers, keep garbage in bins with tight-fitting lids and fix leaky taps (Health Canada).
• For mice, use many snap or electronic traps along the walls, 1 trap per metre, and check every trap daily (Health Canada).
• Skip glue traps and live traps (CDC). Poison comes last: always in a bait station (PMRA), and only products with a PCP number on the label, which shows Health Canada approval.
• Need help? Get a quote from a recommended local exterminator through Pest Agent's referral form.

Mice start looking for warmth as temperatures fall toward winter, and since they do not hibernate, a house with one open gap offers them a whole season of shelter, which is where rodent control usually begins. By the time scratching starts in the walls at night, the question is no longer whether rodents can get in but how many already have.

The order of the steps matters more than any single product. Poison set out before the gaps are sealed and the food is put away is a classic way to get that order wrong, and it can leave poisoned mice dying out of sight while new ones keep arriving.

What Is Rodent Control?

Rodent control is the set of methods used to get mice and rats out of a building and keep them out. It is not a single product or a single visit. It is a plan that starts with prevention and only uses poison when other methods are not enough. Our mice hub gathers every guide on the topic if you want to go deeper.

The Integrated Approach

The integrated approach to rodent control puts the methods in a set order. UC IPM, the University of California's pest management program, lists the steps as ongoing sanitation, exclusion (sealing entry points), trapping, and baiting only as a supplement once exclusion and sanitation are in place. Health Canada makes the same point: baits or poisons should not be used as the only method to control rats and mice. If you skip the sealing and cleaning, new rodents simply replace the ones you remove.

Why Rodent Control Matters

Rodent control matters because mice and rats carry disease and damage property, according to Health Canada. The deer mouse is the most common carrier of hantavirus in Canada, which is why you should never sweep or vacuum dry droppings. Rodents also breed fast: a female house mouse can have 5 to 10 litters a year (UC IPM). Health Canada advises dealing with occasional invaders right away so a few mice do not turn into a severe infestation.

Mice or Rats?

Mice or rats is the first question to answer, because traps and gap sizes are different for each. Rats are much larger than mice and can weigh up to 0.5 kg (1 lb), and a rat trap is too big to catch a mouse reliably. Our guide to telling a mouse from a rat covers droppings, size and tails.

Signs You Need Rodent Control

Signs you need rodent control include scratching or scampering sounds in the walls at night, gnaw marks, damaged food packages, droppings and urine, holes or burrows along the foundation, and tracks on dusty surfaces (Health Canada). Rats can also leave dark smudge marks along beams, pipes and walls where their fur rubs (UC IPM).

How Does Rodent Prevention Work?

Rodent prevention works by closing the gaps mice and rats use to get in and removing the food, water and shelter that keep them there. It is the part of rodent control that lasts, and it is worth doing even after the last mouse is trapped. For a full room-by-room plan, see our guide on how to keep mice out of your house.

Sealing Entry Points

Sealing entry points is the core of rodent prevention. Health Canada says mice can squeeze through cracks as small as a dime and rats through a quarter-sized hole, and even a worn door threshold lets mice in. UC IPM puts the mouse limit at about 1/4 inch (about 6 mm). Use materials rodents cannot chew:

• Metal weather stripping under doors, and weather stripping on windows
• Steel wool stuffed around pipes before caulking or plastering
• Fine mesh metal screening over dryer vents, attic vents and soffits
• Mortar or concrete patches for foundation cracks

Plastic screening, rubber, vinyl, insulating foam and wood do not hold, because mice gnaw through them (UC IPM). To find the gaps, follow our guide on finding mouse entry points, and do not forget the roof: here is how to stop mice from climbing your chimney.

Food Storage

Food storage cuts off what draws rodents inside. Health Canada recommends storing dry food and dry pet food in metal or glass containers and keeping garbage in containers with tight-fitting lids. Never put fatty or oily food waste, eggs or milk products in the composter. Outside, York Region suggests bird feeders with trays and cleaning up spilled seed often, since fallen seed can feed mice and rats.

Water Sources

Water sources are easy to overlook. Fix leaky taps, sweating pipes and open drains (Health Canada), especially in basements, laundry rooms and under sinks.

Clutter

Clutter gives rodents safe places to nest. Clear unused boxes and piles in the house and garage, and raise woodpiles about 30 cm (1 foot) off the ground, away from the house (Health Canada). UC IPM notes that clean conditions alone rarely eliminate mice, but removing shelter can make every other method work better.

Fall Rodent Season

Fall rodent season is when most Canadian homes see mice. Mice often look for food, water and warmth as temperatures drop, and they do not hibernate (Orkin Canada), so seal and clean up before the first cold nights rather than after you hear scratching in the walls.

How Does Mouse Control Work?

Mouse control works best with many traps, set right away, along the walls where mice travel. Trapping lets you confirm each catch and avoids the hidden dead mice that poison can leave behind. Our step-by-step guide on how to get rid of mice walks you through the whole process.

Snap Traps

Snap traps are the standard tool for mouse control. Health Canada calls snap and electronic traps easy to use and very effective when well positioned and set properly. Bait them with a small amount of a strong-smelling, sticky food such as peanut butter. See our tested picks for the best mouse trap.

Electronic Traps

Electronic traps typically kill with a high-voltage shock once the mouse walks into the tunnel, and models such as the Victor Electronic Mouse Trap let you empty them without seeing or touching the mouse. They work on the same placement rules as snap traps and suit people who find snap traps hard to set or unpleasant to empty.

Trap Placement

Trap placement matters more than the trap model. Health Canada recommends:

1. Set 1 trap per metre along walls, or 5 to 10 traps per visible mouse hole.
2. Bait the traps without setting them for 3 to 4 days so mice get used to them.
3. Then set them, and check every trap daily.
4. Reset the traps after 2 to 3 weeks to catch young mice that have matured.

Mice rarely travel more than about 9 metres from their nest (UC IPM), so put traps close to where you see droppings, not across the house.

Traps to Avoid

Traps to avoid are glue traps and live traps. The US Centers for Disease Control and Prevention (CDC) advises against both, and UC IPM notes that glue traps carry a greater potential for exposure to hantavirus and live traps quickly become contaminated with mouse urine. If you do use a live trap, UC IPM notes that relocating live-caught mice is not an effective solution.

Ultrasonic Repellers

Ultrasonic repellers are not a reliable form of mouse control. Health Canada notes that rodents may adapt to them and return, so they should only be used alongside other methods, and UC IPM states that high-frequency devices are not effective.

Rodent Poison Rules in Canada

Rodent poison rules in Canada are strict. Health Canada and its Pest Management Regulatory Agency (PMRA) set these rules:

• Health Canada says to buy only products with a Pest Control Products (PCP) number on the label, which shows its approval.
• The Government of British Columbia says to use domestic (consumer) rodenticides only in tamper-proof bait stations, and they are often sold packaged with one.
• Consumer products cannot contain second-generation anticoagulants such as brodifacoum, bromadiolone or difethialone, which the Government of British Columbia also restricts.
• Commercial class products must be applied by a certified professional.

British Columbia goes further. Since January 21, 2023, the Government of British Columbia restricts the sale and use of second-generation anticoagulant rodenticides, with exemptions only for some essential services.

Poison Risks

Poison risks are why rodenticides come last. Poisoned rodents can die out of sight inside walls, and the Government of British Columbia notes that pets, children and wildlife can die or be seriously hurt if they eat the poisoned bait. Animals that eat a poisoned rodent can be poisoned too (UC IPM). Always read the label, keep bait stations out of reach of children and pets, and never place loose bait.

Knowing the Mice Are Gone

Knowing the mice are gone takes patience. The CDC suggests that a full week with no catches and no new droppings means the infestation is likely over. Keep a few traps set along walls afterwards as an early warning.

How Is Rat Control Different From Mouse Control?

Rat control differs from mouse control because rats are bigger, warier and range farther from their nests. The same order applies (seal, clean, trap), but the details change.

Trap Shyness

Trap shyness is the main reason rat control takes longer. According to UC IPM, rats tend to notice and avoid new objects and new foods, so they may ignore traps for several days or weeks. Leave rat traps baited but unset, usually until the bait has been taken several times, then set them all at once.

Rat Trap Placement

Rat trap placement depends on the species. UC IPM recommends spacing traps about 10 to 20 feet (about 3 to 6 metres) apart, along walls, behind objects, in dark corners and near droppings or burrows. Norway rats may forage 100 to 500 feet (about 30 to 150 metres) from their nests, so a rat problem often starts in the yard or a neighbouring property.

Norway Rats Versus Roof Rats

Norway rats versus roof rats is a ground versus height question. Health Canada describes the Norway rat as a burrower that builds tunnels at ground level, and the roof rat as an agile climber that prefers trees, vines and dense plants. For roof rats, UC IPM suggests placing traps off the ground on ledges, pipes or beams, trimming tree limbs within about 6 feet (1.8 metres) of the roof and keeping dense plants about 2 feet (about 60 cm) from the walls. Young rats may squeeze under a door through a gap of about 1/2 inch (13 mm), so use sturdy door sweeps and 1/2-inch wire mesh rather than chicken wire on vents.

Rat Control in Alberta

Rat control in Alberta is a provincial program. Norway rats were first found in the province around 1950, and Alberta has had no breeding rat populations for about 70 years, largely thanks to a Rat Control Zone about 600 km long and 29 km wide along the Saskatchewan border. Usually only a few infestations are confirmed each year. If you see a rat in Alberta, report it to the province at 310-FARM (3276).

What Does a Professional Rodent Control Service Include?

A professional rodent control service combines an inspection, exclusion work, trapping or bait stations and follow-up visits. Here is what Canadian companies typically describe, so you know what to expect and what to ask for. If you are specifically comparing mouse exterminators, our guide to hiring a mouse exterminator covers that decision.

Inspection

Inspection comes first. A technician checks the inside and outside of the home for entry points, droppings, gnaw marks and nests, identifies the species, and should review the findings with you before any treatment.

Exclusion Work

Exclusion work is the sealing of entry points with rodent-resistant materials such as galvanized mesh, metal flashing and sealants. Some companies also install one-way doors that let rodents leave but not come back in. Ask which gaps will be sealed and whether the work is guaranteed.

Trapping

Trapping by a professional uses snap traps and multi-catch traps, placed in high-activity areas with children and pets in mind. The difference is experience with placement and regular checks.

Bait Stations

Bait stations used by professionals are usually exterior, anchored, locked and tamper-resistant, Orkin Canada describes them as a last resort, and the National Pesticide Information Center suggests a combination of control methods. Professionals can use commercial class products that homeowners cannot buy, but the same label and PCP rules apply.

Follow-Up Visits

Follow-up visits check traps and bait stations and confirm the rodents are gone. Many companies include free re-treatment for a set period: for example, one Toronto company advertises a 100-day warranty. Ask how many visits are included and what happens if rodents return.

Year-Round Plans

Some companies also sell year-round prevention plans, which add scheduled inspections and bait station servicing through the year, often with a refill before cold weather. They suit homes with recurring problems, for example houses near fields and woodlands, where Health Canada notes deer mice may move into buildings in the fall.

Cleanup

Cleanup of droppings and contaminated insulation is offered by some companies and not others, so ask before you book. If you do it yourself, follow our guide on how to clean mouse droppings safely.

How to Check a Licence

Checking a licence protects you, and the Government of British Columbia advises contacting a licensed pest control company for a rodent problem. In Ontario, for example, a pest control business generally needs an operator licence with a licensed exterminator in charge at each location, and it must display that licence. Prices vary by province, home size and the scope of work: one Toronto company lists residential rodent treatments at about $200 to $400. Our guide to mouse exterminator costs explains what drives the price, and you can get a quote from a recommended local exterminator through Pest Agent's referral form. If you rent, contact your landlord first: in Ontario, for example, York Region notes that landlords must take action to control pests.