Oriental cockroaches thrive in cool, damp environments and are strongly associated with moisture issues. They often live outdoors in soil or debris but can move indoors through drains, cracks, and ground-level openings. They are less mobile than other species and tend to stay close to moisture sources. Because of this, infestations are often concentrated in basements, crawl spaces, or areas with plumbing leaks or poor drainage.

Common signs include slow-moving cockroaches near drains, a musty or unpleasant odor in infested areas, and increased activity in damp environments. They can contaminate surfaces and food and may contribute to unsanitary conditions. Their presence is often a strong indicator of underlying moisture or sanitation issues that should be addressed alongside treatment.