The American cockroach is the largest cockroach commonly encountered in and around homes. It prefers warm, damp environments such as basements, floor drains, sewers, and utility rooms, and can enter buildings through drains, sewer connections, and gaps around pipes.
Although less prone to indoor breeding than the German cockroach, American cockroaches can fly short distances and are strong runners, which makes them unsettling to encounter. Their presence is often tied to moisture problems, so control usually pairs targeted treatment with fixing damp conditions and sealing entry points around plumbing.