Oriental Cockroach
The damp-basement cockroach. Slower and less wary than the others, and the one species that does not want a warm, dry room.
Blatta orientalis
- Length
- About 25 mm
- Colour
- Dark brown, almost black
- Scientific name
- Blatta orientalis
How to identify it
The male's wings cover roughly three-quarters of the abdomen and are darker than it. The female's are only partly developed, so she looks almost wingless.
Because it travels up the outside of pipework, an Oriental cockroach problem in an upper unit often starts in a basement several floors below.
Life cycle and behaviour
Why this species behaves the way it does, and what that means for how long treatment takes.
- Each capsule holds about 16 eggs, and a female drops 8–14 of them, more or less wherever she happens to be.
- Capsules take around 60 days to hatch, and nymphs moult seven times before reaching adulthood.
- Adults can live up to two years — the longest-lived of the common species.
- They prefer to live in colonies, so numbers build up fast around a single moisture source.
Where we find it
The harbourage points we check first on a Oriental Cockroach call.
Dark, damp crevices in basements, utility runs, and service tunnels
Around basement water leaks, behind toilets, baths, and laundry tubs
Sewer pipes — it climbs the outside of water pipes to reach upper floors
Outdoors in mild weather: alleyways, under verandas, and around garbage
How cockroaches are actually controlled
Cockroaches need food, water, and shelter. Removing any one of them puts the population under stress, and that does more long-term good than spraying ever will.
Cut the water first
Condensation on a cold water pipe is enough to sustain a colony on its own. Fixing leaks and bringing humidity down removes the hardest resource for them to replace.
Close the harbourage
Cockroaches are thigmotactic — they settle in cracks tight enough to touch their backs and bellies at once. Caulking crevices around plumbing, cabinets, outlets, and countertops takes those spaces away permanently.
Clean before treating, not after
Residual product applied to greasy or dirty surfaces is close to useless. Degreasing and HEPA vacuuming first both removes insects physically and lets the treatment work as intended.
Monitor to find the hotspots
Traps behind the fridge, under the sink, inside cabinet voids, and in bathroom vanities show where the population actually sits, so treatment goes where it counts instead of everywhere.
Source: Ontario Pesticide Training & Certification — Appendix A: Pests of Structures, and Appendix B: IPM for Structural Pests.
Other Cockroach Control species
Not sure which one you have? Compare the others we treat in Ontario.
German Cockroach
The most common and most prolific cockroach in Ontario buildings, and the one behind the majority of kitchen and bathroom infestations.
Brown-banded Cockroach
Hides higher up and further from water than other species, so it turns up in living rooms and bedrooms rather than only kitchens.
American Cockroach
The largest cockroach found in Ontario, most often a commercial problem in kitchens, bakeries, and heated utility tunnels.
Pennsylvania Wood Cockroach
An outdoor species that wanders into homes and cottages. It will not establish an indoor infestation, which changes the response entirely.
Send us a photo and we'll identify it
Correct identification decides the treatment. A licensed technician will confirm the species before anything is applied.