Most Surrey homeowners don’t realize they have a rodent problem until it is well established. Rats and mice are nocturnal, cautious, and surprisingly quiet in the early stages. By the time you see one during the day or hear scratching at night, the population inside your walls may already be larger than you think.
Here is how to tell if you have rats or mice in your Surrey home, what each warning sign actually means, and when the evidence points to something that needs professional attention.
Droppings in Unexpected Places
Rodent droppings are usually the first hard evidence homeowners find. The location and size tell you what you are dealing with.
Rat droppings are dark, capsule shaped, and roughly the size of a grain of rice or larger. Norway rats leave droppings along baseboards, behind appliances, and in crawlspaces. Roof rats leave them in attics, on top of insulation, and along rafters.
Mouse droppings are much smaller, about the size of a sesame seed, and are often scattered in greater numbers. Check inside kitchen drawers, under sinks, behind the stove, and along pantry shelves.
In Surrey, the most common areas to find droppings are garages (especially near stored pet food or garbage bins), crawlspaces under older homes in Whalley and Newton, and attics in South Surrey and White Rock where roof rats access through mature tree canopy.
Fresh droppings are dark and moist. Dry, crumbly droppings indicate past activity, but do not assume the problem is gone. Rodents often shift between active zones depending on the season.
Scratching and Scurrying Sounds at Night
If you are hearing noises in your walls, ceiling, or attic between dusk and dawn, rodents are the most likely cause. Rats produce heavier, more deliberate sounds. Mice are lighter and faster, often described as a quick scurrying overhead.
The timing matters. Rodents are most active in the first few hours after dark and again before dawn. If you are hearing sounds during the day, the population has likely grown large enough that competition for space is forcing some animals to forage outside their normal schedule. Daytime activity is a sign of a larger infestation.
Surrey homes along the Fraser River corridor, in Newton, and near agricultural edges in Cloverdale tend to experience rodent noise complaints earlier in the fall as temperatures drop and outdoor food sources thin out.
Grease Marks and Rub Trails
Rats follow the same paths repeatedly. Their fur carries body oils and dirt that leave dark, greasy streaks along walls, baseboards, pipes, and beams. These rub marks are especially visible along known travel routes in garages, crawlspaces, and attic access points.
Look for consistent dark smudges at the same height along a wall, or around holes and gaps where rodents squeeze through. If the marks are fresh and smeared, the route is still active. If they are dry and faded, the path may be older, but the entry point likely still exists.
In townhome complexes across Fleetwood and Clayton, rub marks often appear along shared plumbing chases and utility conduits, which is a sign that rodents are travelling between units.
Gnaw Marks on Materials
Rodents need to gnaw constantly to keep their teeth worn down. Rats can chew through wood, plastic, soft metals like aluminum, and even concrete in poor condition. Mice focus on softer materials but will gnaw through drywall, food packaging, and electrical wire insulation.
Common gnaw evidence in Surrey homes includes chewed garage door seals, damaged weather stripping around exterior doors, holes in drywall near pipes, and shredded insulation in crawlspaces and attics.
Electrical wire damage is a serious concern. Rodent gnawing on wiring is a documented cause of residential fires. If you find chewed wires in your attic or crawlspace, address the rodent issue and have an electrician inspect the damage.
Nests and Nesting Material
Mice build small, round nests from shredded paper, fabric, insulation, and cardboard. Rats create larger, messier nests in hidden voids. Common nesting locations in Surrey homes include wall cavities, behind major appliances, in the back corners of storage rooms, under bathtubs, and deep inside attic insulation.
If you find nesting material but no droppings nearby, check a wider area. Rodents often nest in one zone and forage in another, especially in larger homes or multi unit buildings.
Tracks and Footprints
In dusty areas like crawlspaces, unfinished basements, and attics, you may see small footprints or tail drag marks. You can test for active routes by lightly dusting flour or talcum powder along a suspected path and checking the next morning.
This is particularly useful in older Surrey homes with exposed dirt crawlspaces, which are common in neighbourhoods built before the 1980s across Whalley, Guildford, and Newton.
Unusual Pet Behaviour
Dogs and cats often detect rodents before you do. If your pet is suddenly fixated on a specific wall, cabinet, or area of the house, pawing at baseboards, or refusing to settle at night, they may be hearing or smelling rodent activity that you cannot.
A Strong, Persistent Smell
A heavy ammonia-like odour in enclosed spaces such as garages, crawlspaces, utility rooms, or under sinks can indicate a significant rodent presence. The smell comes from urine, which rodents deposit continuously along their travel routes.
In severe cases, or when a rodent dies inside a wall or duct, the odour becomes unmistakable. If you notice a sudden, strong smell from a wall cavity or ceiling space, it is worth investigating even if you have not seen other signs.
What to Do If You See Multiple Signs
One or two droppings near the garage door might mean a single mouse tested your defences. But if you are finding droppings in multiple rooms, hearing sounds at night, seeing grease marks along walls, and noticing gnaw damage, you are dealing with an established infestation that will not resolve on its own.
At that point, DIY traps and store bought solutions rarely keep up with the reproduction rate. A single pair of mice can produce dozens of offspring in a matter of months. Rats reproduce more slowly but cause significantly more structural damage per animal.
The most effective approach is a professional inspection to map the full extent of the problem, identify every entry point, and set up a targeted removal and exclusion plan. For prevention steps you can take right now, see our guide on keeping rats and mice out of your Surrey home. In Surrey, where mild winters allow rodents to stay active year round, exclusion (physically sealing the building) is the only method that delivers lasting results.
If you are seeing these signs in your home, contact a rat and mouse control team in Surrey who can inspect your property, set up a treatment plan, and seal entry points so the problem does not come back.
