German roaches don't come from outside. They arrive in boxes, bags, and used appliances, and they stay where three things meet: warmth, water, and grease. That's why the kitchen — specifically the voids behind and under appliances — is almost always the whole story.
Read the kitchen first
Before treating anything, look: behind the fridge compressor, under the sink, inside cabinet hinges, around the dishwasher. Fecal spotting tells you where they actually live, which is rarely where the customer sees them run. Treat the harborage, not the sighting.
What actually closes cases
- Bait in the voids, placed where they aggregate — small placements, many of them, refreshed as they're consumed.
- Growth regulators to break the breeding cycle, because one egg case carries dozens of chances to restart.
- Sanitation with specifics: degrease the stove sides, clear the cardboard (they eat the glue and hide in the corrugation), fix the drip under the sink.
- Follow-up on schedule. German roach work is won on the second and third visits, not the first.
In multi-unit buildings
One infested unit seeds the neighbors through shared walls and plumbing chases. The honest recommendation is always building-level coordination — treating one unit of an infested building is renting progress, not buying it.