Overhead or underground pipes, conveyor belts, and augers commonly found in farm buildings and factories are often used as entry points and routes into and between buildings. Such equipment, particularly if abandoned, may provide harborage as well as food. Utility entry points must be constantly monitored for excess openings caused by equipment repair, installation, or modification. Outside walls and doors must also be monitored for damage from equipment or livestock and for damage or wear from heavy use. If work patterns require doors to be open during hours of darkness, when rodent entry is most likely, rodent barriers may be needed, such as a solid fence or wall or a metal wing wall between the foundation and adjacent loading dock areas .

Buildings constructed with ribbed or corrugated metal siding allow rodent entry if the bottoms of the siding panels do not rest flat on a solid surface or they are not otherwise closed off. Sections of prefabricated buildings should be assembled tightly, and gaps at joints should be covered with metal flashing. Often, however, they are left open, especially at corners and at the foundation/slab interface. Roll-up or overhead doors often provide easy entry for rodents, birds, and bats. With the door closed, check for gaps along the sides, bottom, and top of the door (Fig. 8). A gap at the top is common. Rats and mice can easily climb up the space between the door and the inner wall or track to the top, where they gain entry and climb down the inside of the track.

Gaps between the track and the wall are also common, especially if the track has been installed on brick walls. Door bottoms may be bent or damaged, leaving gaps along the floor. Uneven floors due to frost heaves may leave gaps when the door is closed.

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