7 Warning Signs You Have a Rat Problem in Your Kent Home

1Rat droppings are the most definitive evidence of an active infestation. Norway rat droppings measure 3/4 inch (19 mm) long, are dark brown to black, and have blunt ends. Roof rat droppings are smaller - 1/2 inch (12 mm) - with pointed ends. Fresh droppings are soft and glisten; droppings older than three days harden and fade to grey.

Location matters as much as the droppings themselves. Droppings concentrated along walls, behind appliances, inside cupboards, or near food storage areas indicate active feeding zones. Finding 40 or more droppings in a confined area confirms an established colony, not a solitary transient animal. High dropping counts in ceiling spaces or wall voids indicate rats nesting inside the building structure rather than simply passing through.

Norway rat vs roof rat droppings - comparison

2Rats gnaw continuously because their incisor teeth grow at 4–5 inches per year and must be worn down. Gnaw marks appear on structural wood (joists, studs, door frames), electrical wiring insulation, plastic plumbing pipes, and cardboard food packaging. The NPMA identifies electrical wire damage from rodent gnawing as a contributing factor in 20–25% of unexplained house fires in the United States.

Rat gnaw marks display two parallel ridges from incisor teeth and measure approximately 1/8 inch wide. Fresh gnaw marks are light-coloured; older marks darken with age. Smooth, single-toothed gnaw marks indicate mice rather than rats. Finding gnaw marks on live electrical wiring requires immediate action - chewed wiring creates fire risk independent of the infestation itself.

In Kent homes built before 1990, rats frequently gnaw through the original ABS or copper plumbing connections in crawl spaces, causing slow leaks that feed the moisture conditions attracting further pests. For properties along the Soos Creek corridor, where crawl space moisture is elevated, this combination is particularly common.

3Rats navigate by touch, following the same routes repeatedly with their bodies pressed against walls. This behaviour deposits a dark, greasy smear from body oils and dirt accumulated in their fur. Rub marks appear as dark smudges along baseboards, at floor level near wall edges, and on the sides of entry points such as gaps around pipes or joists.

Fresh rub marks are soft and greasy to the touch. Older marks are hard and encrusted. Multiple dark marks along a single wall section confirm an established run - a route used by the same colony daily. Rub marks around a hole 2 inches or larger in a wall, floor, or ceiling indicate a primary entry or exit point used by the colony. Sealing these points is a core component of exclusion treatment.

4Norway rats are nocturnal and peak in activity between midnight and 4 a.m. Sounds heard inside walls, under floors, or in the ceiling space during these hours are a reliable indicator of an active rat presence. Common sounds include: scratching (nails on wood or drywall), scurrying (rapid movement between wall voids), gnawing (rhythmic chewing on hard surfaces), and squeaking (social vocalisations within the colony).

The location of sounds identifies where rats are nesting and travelling. Sounds in the attic or upper ceiling indicate roof rats or Norway rats nesting above the insulation. Sounds under floors or in crawl spaces indicate Norway rats nesting in the substructure. Sounds inside the wall cavity between the kitchen and a neighbouring room indicate a travel corridor connecting the outdoor entry point to an interior food source.

Daytime sounds are a more serious indicator than nocturnal sounds. Rats that forage during daylight hours are typically members of an overcrowded colony where competition for food forces some individuals outside their normal activity window. Daytime rat sightings or sounds in a Kent home indicate a large, established population requiring immediate professional treatment.

5Rats build nests from any soft, fibrous material available - shredded paper, insulation, fabric, cardboard, and plant matter. Nests appear as compact, dense balls of shredded material 6–12 inches in diameter. Common nesting locations in Kent homes include: behind wall insulation in crawl spaces, inside kitchen cabinet bases, beneath appliances with floor-level heat output (dishwashers, dryers), inside stored boxes in garages, and in the corner voids of attic spaces.

A nest containing pups (young rats without fur) or a nursing female confirms active breeding. Breeding pairs produce 4–6 litters per year with 7–12 offspring per litter. WSU Extension documents that Norway rats in the western Washington lowlands breed year-round due to mild winter temperatures, unlike inland populations that experience seasonal breeding suppression.

6Rats consume 1 ounce of food per day and contaminate 10 times that amount through droppings, urine, and fur. Signs of rat feeding activity include: chewed holes in bags of rice, flour, or pet food; gnawed corners on cardboard boxes; partially eaten fruit or vegetables; and smeared droppings or urine staining inside food storage areas. Rats prefer high-carbohydrate foods - cereals, grains, and fruits - but consume meat, pet food, and compost when alternatives are unavailable.

Food contaminated by rats poses a direct public health risk. The CDC identifies salmonellosis as transmissible through rat urine and faeces on food contact surfaces. Any food with evidence of rat contact must be discarded. All food in an infested area should be transferred to hard-sided, rat-proof containers - rats gnaw through cardboard and thin plastic within minutes.

7Norway rats are burrowing animals that excavate tunnel systems 12–18 inches deep under foundations, concrete slabs, decking, and wood piles. Burrow entrances measure 2–4 inches in diameter, are circular, and have smooth, compressed edges from repeated use. Fresh burrows have a fan-shaped dirt scatter at the entrance. Abandoned burrows accumulate debris and cobwebs at the entrance opening.

Burrows directly under the foundation of a Kent home create voids that allow cold air, moisture, and further pest entry. Multiple burrows in a cluster indicate a colony rather than a single animal. Norway rat burrows connected to the exterior of the home require both colony elimination and structural exclusion - removing the colony without sealing the burrows allows reinfestation from neighbouring areas within weeks.

Check the following exterior locations during a self-inspection: the gap between the concrete foundation and wood sill plate, soil along fence lines adjacent to compost or waste bins, under wood decking, around conduit or pipe penetrations through foundation walls, and in ornamental rock beds against the house perimeter.