What structural connection is surprisingly common for linking exterior harborage to interior cockroach activity?

Answer

Poorly sealed utility lines where conduits enter the home

Utility lines—where water, gas, or electrical conduits enter the dwelling—often serve as direct, sheltered pathways connecting exterior harborage areas to interior spaces like basements or utility closets.

What structural connection is surprisingly common for linking exterior harborage to interior cockroach activity?
locationinsectpestAmericacockroach