Why are cockroaches hard to get rid of in apartments?
Because they move between units through shared walls, plumbing and electrical chases, and treating one apartment leaves the others as a source. Cockroaches also breed quickly and hide in tight spaces. Control works best when neighbors and management are involved and sanitation is addressed throughout the building.
Think of a building as one habitat. A kitchen in unit 3 and a kitchen in unit 4 share a pipe chase, and a roach does not care about a lease. A technician may ask to look at adjacent units for this reason.
If you rent, tell the landlord in writing. For information on Washington's rental pest rules, see our guide on bed bugs and landlord duties, which sets out the state statutes. Rules for roaches specifically are not summarized here.
What do cockroaches want from a kitchen?
Food, water and hiding places. Crumbs, grease, pet food and open garbage supply the first, leaky pipes and damp sponges the second, and cracks behind appliances, in cabinet corners and around plumbing the third. Removing any one of these makes treatment work better, and removing all three works best.
Wipe counters at night, store dry food in sealed containers, take out the trash and fix drips. A sink with a dripping trap is a nightly water supply.
Cardboard is a hiding place and a way to carry roaches in. Break down boxes and keep them out of the kitchen.
- Seal food in hard containers
- Fix drips and wipe sinks dry
- Clean grease behind the stove
- Empty trash daily and keep lids on
- Break down cardboard promptly
What about restaurants and shared kitchens?
Food businesses need a scheduled program that includes inspection, monitoring, sanitation advice and records, since cockroaches can threaten a health inspection and a reputation. The technician works with staff to find hiding places and recommends changes to storage and cleaning routines.
Commercial kitchens have more food, more heat and more hiding places than a home. Floor drains, equipment legs, walk-in coolers and storage rooms all matter. Timing visits for off-hours helps.
We do not summarize health department inspection rules here. Ask your local health authority for the requirements that apply to your business. The commercial pest control page covers programs.
Are cockroaches harmful?
They can contaminate food and surfaces and are associated with allergies and asthma in some people. We cite no Washington-specific data for this. Treat them as a hygiene problem and a reason to act, and talk to a doctor about health concerns. Pesticide use should always follow the label.
Do not use foggers or total-release products, which scatter roaches into walls and can leave residue where food is prepared.
After treatment, keep surfaces clean but avoid wiping bait placements. Wiping them off removes the bait.
