Wicomico County, MD Public Health Rules: Rodent Control (2026)

Section 160-58, in Article IX's environmental-deficiencies group, is Wicomico County's rodent-proofing standard for every structure in the unincorporated county. Subsection A sets the trigger: any opening a half-inch or larger that rodents could reach must be rodent-proofed under the rest of the section. Subsection B covers windows, lighting, ventilation or other openings that sit below grade or within 24 inches of ground level, or that are otherwise accessible to rodents; those must be covered with grilles, expanded metal, screens or hardware cloth attached to sturdy frames that leave no exposed wood a rodent could gnaw through.

Subsection C extends the same standard to below-grade stairway, elevator-shaft and coal-hole openings, requiring tight-fitting metal covers flashed with 24-gauge galvanized sheet metal, and it requires the adjacent wall itself to be built of rodent-proof material. Later subsections reach utility-pipe penetrations, which must be sealed solidly or fitted with a 24-gauge metal collar extending at least three inches past the opening; skylights and roof vents accessible to rodents, which must be screened; outdoor storage, which must be stacked at least eight inches off the ground and away from exterior walls; basement floors in direct earth contact, which must be paved with a rodent-impervious material; and exterior wooden doors where rodents have already gotten in, which must be fitted with a sheet-metal cuff along the bottom eight inches.

The section also reaches gaps between adjacent buildings too narrow to inspect, requiring them to be sealed without blocking stormwater drainage. Article IX's companion Sections 160-55 and 160-57 back this up by requiring accessory structures and premises generally to be kept free of rodent harborage.