How Do You Get Cockroaches? How a Cockroach Infestation Starts in Canadian Homes

How Do You Get Cockroaches?

You get cockroaches when roaches or their egg cases are carried into your home, or when they crawl in from a neighbouring unit or a drain. In Canada, the species that infest homes, mainly the German cockroach, are tropical insects that usually live inside heated buildings, so many new infestations arrive from another building rather than from your backyard.

Groceries

Groceries are one of the most common ways roaches get in. According to Health Canada, cockroaches and their egg cases can hitch a ride on food items, empty beer and soft drink bottles and shipping cartons. The University of Kentucky adds produce boxes, beverage cartons and grocery bags to the list. Cardboard is a favourite hiding place, so unpack and recycle boxes quickly.

Secondhand Furniture

Secondhand furniture and used appliances can carry egg cases you will never spot at a glance. UC IPM advises checking for egg cases glued to the undersides of furniture, inside refrigerator and other appliance motors, and in boxes. Inspect any used couch, dresser, microwave or fridge before it comes inside.

Luggage

Luggage and bags are hard to police, and Penn State Extension notes that it is difficult to keep cockroaches from entering homes via boxes, grocery bags and suitcases. Moving day is a high-risk moment, which is why our guide on how to keep roaches from moving with you is worth reading before you pack.

Neighbouring Apartments

Neighbouring apartments are a major source in condos and apartment buildings. German cockroaches travel between rooms and adjoining units along utility pipes and wires and inside wall voids (University of Kentucky). If the unit next door has roaches, they can reach you without ever crossing a hallway.

Drains

Drains let larger species in. American cockroaches forage from sewers into the ground floor of buildings, especially when pipes are damaged, screens are missing or the water traps in drains are faulty (UC IPM). Oriental cockroaches can climb into sinks and tubs through damaged drain pipes. See how to stop cockroaches from coming up the drain.

Outdoor Gaps

Outdoor gaps such as cracks and openings around windows and doors let American and Oriental cockroaches in (University of Kentucky). In Canada, a lone roach found near a door in spring or summer may also be a wood cockroach carried in on firewood or drawn to a porch light. Our guide on where roaches come from covers every route and species in detail.

How Does a Cockroach Infestation Start?

A cockroach infestation starts when one mated female or one egg case gets inside and settles in a warm, hidden spot near food and water. From there, it takes only one hatch for a few roaches to become dozens.

One Pregnant Female Is Enough

One pregnant female is enough to start a cockroach infestation. The University of Kentucky warns that a single mated female can produce an infestation of several thousand new roaches in less than a year. A male, or a wood cockroach that wandered in from outside, cannot start one on its own: Penn State notes that wood cockroaches generally do not reproduce indoors and usually die within a few days.

One Egg Case Is Enough

One egg case is also enough. A German cockroach egg case holds up to 48 eggs, usually 30 to 48 (Penn State). The female typically carries it on the tip of her abdomen until shortly before it hatches, then drops it in a sheltered crack (UC IPM). If that case arrives on a box or a used appliance, the infestation starts the day it hatches.

The First Nymphs Appear

The first nymphs are usually what people notice. Nymphs are young cockroaches: smaller, wingless versions of the adults. The Government of Manitoba notes that cockroaches are often first noticed at the nymph stage, when they start moving around looking for food and water. Seeing several small roaches at once is a strong hint that an egg case has already hatched nearby.

Why You Do Not Notice It at First

Cockroaches are hard to notice at first because they are mostly active at night and tend to spend the day in cracks, behind appliances and under sinks. Health Canada notes they may go unnoticed for some time for exactly this reason. By the time you see one at the kitchen sink at midnight, the colony has often been growing for weeks.

How Fast Does a Cockroach Infestation Grow?

A cockroach infestation can grow fast because a German cockroach female produces a new egg case every several weeks at room temperature (Penn State). The German cockroach is usually the main indoor species in Canada and has been found in buildings as far north as Nunavut, so its life cycle is the one that matters in most homes.

Egg Cases

Egg cases come one after another. A German cockroach female usually produces four to eight egg cases in her lifetime, about one every 6 weeks, and each takes about 28 days to hatch from the time it starts to form (Penn State).

Nymph Growth

Nymphs go through several stages, shedding their skin each time, over a number of weeks before they become adults (Penn State). Penn State notes that German cockroaches are usually found in kitchens and bathrooms, the warm, damp rooms where most infestations take hold.

Adult Lifespan

An adult German cockroach female lives about 20 to 30 weeks (Penn State). During that time she keeps producing egg cases, and her daughters start doing the same once they are adults.

Population in One Year

The population in one year can be huge. Penn State estimates that over 10,000 descendants can be produced in a year from one female, assuming two generations a year. That is why a few roaches in the spring can feel like a sudden explosion by the fall, as explained in our article on why there are suddenly so many cockroaches.

What Causes Cockroaches in a House?

What causes cockroaches to settle in a house is easy access to food, water, warmth and shelter. Health Canada puts it simply: cockroaches will live in any area where food, water and shelter are available. Here is a short version; our guide on what attracts roaches goes deeper.

Food

Food is the first thing roaches look for. They are attracted to starches, sugars and protein (Health Canada) and can eat most food sources, including pet food (Government of Manitoba). Crumbs, grease on the stove and an open bag of kibble are enough to feed a young colony.

Water

Water matters as much as food. Cockroaches are drawn to the warm, damp conditions of kitchens, bathrooms, basements and plumbing areas (Health Canada). A slow drip under the sink or condensation on a pipe gives them a steady supply.

Warmth

Warmth is what keeps cockroaches alive through a Canadian winter. The City of Winnipeg explains that cockroaches are mostly tropical insects, and the ones found in colder climates are usually those that enter buildings. German and brownbanded cockroaches live and breed indoors (UC IPM), so a heated home or apartment is usually all they need year round.

Hiding Spots

Hiding spots near food decide where an infestation settles: cracks around cabinets, the space behind the fridge and stove, and stacks of cardboard or paper. Their droppings contain a natural aggregation pheromone that draws other cockroaches to the same spot (UC IPM), so a good hiding place quickly becomes a crowded one.

Can You Get Cockroaches in a Clean House?

Yes, you can get cockroaches in a clean house. The University of Kentucky notes that even the cleanest home can become infested, and Montreal public health states that anyone can have cockroaches. A clean home makes it harder for roaches to grow in number, but it does not stop an egg case from coming in on a grocery box or roaches walking over from the next unit.

How Do You Stop a Cockroach Infestation Before It Starts?

Stopping a cockroach infestation before it starts means keeping roaches from coming in and catching the first ones before they breed. Health Canada stresses that cleaning and pest control work best together: pesticides alone will not succeed. For a full plan, see our guide on how to prevent cockroaches.

Check What You Bring Inside

Checking what you bring inside is the cheapest protection. Look over used furniture, appliances and boxes before they come in, paying attention to seams, undersides and motor areas. Montreal public health also recommends checking electrical appliances, furniture and food for insects when you move.

Seal Pipe Openings

Sealing pipe openings cuts off the paths roaches use between units and from drains. Health Canada recommends sealing and caulking all cracks, crevices and pipe openings, and putting a fine mesh screen over vents, open pipes and drains.

Store Food in Sealed Containers

Storing food in sealed containers leaves a new arrival with nothing to eat. Keep food in tightly sealed plastic or glass containers rather than cardboard or paper, clean up spills right away, take out the garbage daily and vacuum often to help remove crumbs and egg masses (Health Canada).

Watch for Early Signs

Early signs include small wingless nymphs, droppings that look like dark specks or smears, egg cases in cracks, and roaches seen during the day. Penn State notes that daytime sightings often mean a heavy population, or possibly roaches stressed by a lack of food or water. Our guide to cockroach infestation signs shows what each one looks like.

Use Sticky Traps

Sticky traps are the best way to detect and monitor cockroaches, according to UC IPM. Place them under the sink, beside the fridge and along the base of walls, then check them daily for several days. The traps that catch the most roaches show you where the problem started.

Use Baits Instead of Sprays

Baits are the main tool against a starting infestation, because roaches eat them in their hiding spots. Health Canada says bait stations kill cockroaches about 48 to 96 hours after they eat the active ingredient, and UC IPM notes that a bait program may take 7 days or longer to show results. Penn State warns that sprays and foggers are of little value indoors and can scatter roaches to new spots. Choose products with a PCP number on the label, which shows they are registered with Health Canada, follow the label, and keep baits away from children and pets. For tested options, see our picks for the best cockroach killer.

Tell Your Landlord

Telling your landlord early matters in an apartment or condo. The Government of Manitoba advises tenants to tell their landlord right away and notes that landlords are generally responsible once informed, and UC IPM warns that foggers, bombs and aerosol sprays may disperse cockroaches to other areas.

When to Call a Pest Control Professional

Calling a pest control professional makes sense when you keep catching roaches after a few weeks of baiting, when you see them during the day, or when neighbouring units are also affected. A licensed professional usually starts with an inspection to identify the species and hiding spots, then uses baits, dusts or insect growth regulators, with follow-up visits. Read about what to do if you have cockroaches, or get a quote from a recommended local exterminator through Pest Agent's referral form.