Written by the Gold Standard Pest Solutions team. We are a family run, BPCA certified pest control company based in Gravesend, Kent, with over 40 years of experience protecting homes and businesses across Kent, London and the South East.
The short answer
The most common signs of rats in your house are dark, pellet shaped droppings (around 9 to 14mm long), scratching or scurrying noises in the walls or loft at night, gnaw marks on wood, wires, pipes and food packaging, a strong stale ammonia smell, greasy brown smear marks along skirting boards and walls, and shredded nesting material in quiet corners. If you are seeing one or more of these, you almost certainly have rats rather than mice, and because a pair of rats can produce hundreds of offspring in a year, the problem grows fast. Rats also carry diseases and can chew through electrical cables, so early action matters. If you spot these signs anywhere in Kent, book a professional inspection quickly through our rodent control service rather than waiting to see if it gets worse.
That is the summary. Below we walk through every sign in detail, how to tell rats apart from mice, whether they are dangerous, and exactly when to call in a professional.
What are the first signs of rats in a house?
Rats are secretive and mostly nocturnal, so you will usually notice the evidence long before you ever see the animal itself. The earliest and most reliable signs are droppings, night time noises and a musky smell. Rats are creatures of habit that follow the same routes every night, which is why the clues tend to cluster in the same spots. Here are the twelve signs we look for on a Kent callout, roughly in the order homeowners tend to notice them.
1. Droppings
Droppings are the number one giveaway. Rat droppings are dark brown to black, shaped like a grain of rice but larger, and typically 9 to 14mm long with pointed ends. You will often find them in groups near food sources, under sinks, along skirting boards, in the loft or in kitchen cupboards. Fresh droppings are dark and shiny, while older ones turn grey and crumble. A single rat can leave up to 40 droppings a night, so if you find a scattering, the infestation is already established.
2. Scratching and scurrying noises at night
If you hear scratching, gnawing or scurrying above the ceiling or inside the walls after dark, that is a classic sign of rats. Rats are most active at night, and lofts, wall cavities and spaces under floorboards make perfect nesting sites. Many of our Kent customers first call us because of “banging or scratching in the loft at night” that keeps them awake. You may also hear squeaking.
3. Gnaw marks
Rats’ teeth never stop growing, so they gnaw constantly to keep them worn down. Look for teeth marks on skirting boards, door frames, food packaging, plastic pipes and cables. Fresh gnaw marks are pale and rough; older ones are darker and smoother. Chewed electrical wiring is one of the most dangerous signs because it is a genuine fire risk.
4. Greasy smear marks
Rats have poor eyesight and follow the same paths using their whiskers and body, brushing against walls as they go. Over time the grease and dirt in their fur leaves dark, greasy smear marks along skirting boards, around holes and at the bottom of walls. Greasy marks left along skirting boards are a strong sign of a regular, established rat run.
5. A strong, stale ammonia smell
A persistent musky or ammonia like smell, especially in an enclosed space like a loft, cupboard or under the floor, often means rats are nesting nearby. The smell comes from their urine, which they use to mark territory. If the smell is strong, the population is likely large or long established.
6. Nests and shredded material
Rats build nests from anything soft they can shred, loft insulation, cardboard, paper, fabric and packaging. Finding a pile of shredded material in a quiet, warm, hidden spot usually means a nest is close by.
7. Rub marks and dark trails
Along with greasy smears, you may notice darker rub marks where rats squeeze through gaps repeatedly. These often appear around pipe entries, air bricks and the edges of loft hatches.
8. Footprints and tail marks
In dusty or little used areas, rats leave footprints and tail drag marks. A classic professional trick is to sprinkle a light dusting of flour or talc in a suspected area overnight and check for tracks in the morning.
9. Damaged food packaging
Chewed cereal boxes, gnawed fruit and holes in stored food are obvious signs. Rats will also drag food away to eat in private, so missing or moved food is worth noticing.
10. Burrows and holes outside
In gardens, rats dig burrows near compost heaps, decking, sheds and under paving. Smooth, well used holes about 6 to 10cm wide, often with a run of flattened earth leading to them, point to an outdoor colony that may already be moving indoors.
11. Your pets are acting strangely
Cats and dogs often detect rats before you do. If your pet is suddenly fixated on a wall, cupboard, appliance or the loft hatch, pawing or sniffing at it, they may be reacting to rodents you cannot yet hear.
12. Seeing a rat in daylight
Rats usually avoid people, so seeing one in the daytime often means the nest is overcrowded and they are being forced out to find food. Spotting a rat during the day is a sign the infestation is well advanced.
What do rat droppings look like compared to mouse droppings?
This is one of the most useful things to get right, because it tells you what you are dealing with and how urgently to act. Rat droppings are much larger than mouse droppings, and the treatment differs. Here is a quick comparison.
| Sign | Rats | Mice |
|---|---|---|
| Dropping size | 9 to 14mm, rice grain shape, pointed ends | 3 to 6mm, thin, dark, pointed |
| Droppings per night | Up to 40 | 50 to 80, more scattered |
| Noise | Louder scratching, scurrying, gnawing | Faint scratching and squeaking |
| Gnaw marks | Larger, deeper on wood, pipes, cables | Small, fine teeth marks |
| Smell | Strong ammonia | Musky but fainter |
| Where they nest | Lofts, wall cavities, under floors, garden burrows | Wall voids, behind units, lofts |
| Typical entry gap | About 20mm or larger | As small as 6mm |
If the droppings are large and you are hearing heavier movement, you are dealing with rats. For mice specifically, we cover the warning signs and timing in our guide on when to call pest control for mice.
Signs of rats in the loft
The loft is one of the most common places rats settle in a Kent home, because it is warm, dry, undisturbed and full of insulation to nest in. Signs of rats in the loft include scratching or rolling noises overhead at night, droppings scattered across the insulation or near the loft hatch, disturbed or shredded insulation, gnawed joists or cables, and greasy trails along the timbers. Because rats reach the loft by climbing cavity walls, pipes and nearby trees, loft activity often means they are using routes through the whole structure of your home.
Signs of rats under the floorboards
Under floor voids give rats a hidden highway between rooms. Signs of rats under the floorboards include scratching or scurrying that seems to come from below you, especially at night, a musty ammonia smell rising through gaps, droppings near air bricks and skirting boards, and gnawed cables or pipes when you lift a board. If your home has suspended timber floors, which many older Kent properties do, this is a common hiding spot.
Are rats in the house dangerous?
Yes. Rats are not just a nuisance, they are a genuine health and safety risk. Rats can spread diseases that affect humans, including Leptospirosis (Weil’s disease), Salmonella and Hantavirus, through their urine, droppings and contact with contaminated surfaces. They also carry fleas, ticks and mites. On top of the health risks, rats cause structural damage by gnawing, and chewed electrical wiring is a recognised cause of house fires. This combination of disease risk and fire risk is exactly why we always recommend dealing with a rat problem quickly rather than hoping it clears on its own.
How are rats getting into my house?
Rats are remarkable climbers and squeezers. A rat can get through a gap of about 20mm, roughly the size of a two pound coin, and can climb brickwork, pipes and cables with ease. Common entry points include gaps around pipes and cables, damaged air bricks, broken drain covers and cracked drainage pipes, gaps under doors, holes in the roofline and eaves, and openings where extensions meet the original building. Rats very often enter through the drains and come up into the house through damaged pipework, which is why a proper inspection checks drainage as well as the obvious gaps.
Blocking these entry points, known as proofing, is the only way to keep rats out for good. We cover general prevention in our seasonal guide, how to pest proof your home: a Kent homeowner’s checklist.
When should you call pest control for rats?
You should call a professional as soon as you confirm two or more of the signs above, or if you see a live rat, hear regular night time activity, or find a cluster of droppings. Rats breed extremely quickly. A single female can have five to ten litters a year with up to a dozen young each time, so a small problem becomes a serious infestation within weeks. Shop bought traps and poisons can knock the numbers down briefly, but they rarely find the nest, rarely block the entry points, and used incorrectly they put pets, children and non target wildlife at risk.
A professional does three things that DIY cannot reliably do: locate and treat the nest and the whole run, safely remove the rodents, and proof the entry points so they cannot come back. That is the difference between a quick fix and a lasting one.
How Gold Standard deals with rats across Kent
Our BPCA certified technicians handle rat problems in homes right across Kent, including Gravesend, Dartford, Ashford, Canterbury and the surrounding towns, in discreet unmarked vehicles. A typical visit starts with a full survey to find the droppings, runs, entry points and nest, followed by a targeted treatment plan, safe removal, and proofing advice to seal the gaps for good. We will also tell you honestly if what you are hearing turns out to be something else, because not every noise in the loft is a rat.
If any of the signs in this guide sound familiar, do not wait for it to get worse. Book a fast, no obligation inspection through our rodent control in Kent service, or see the full range of home treatments on our residential pest control page. Catching rats early is always cheaper, cleaner and less stressful than dealing with a full infestation.
Frequently asked questions
What is the very first sign of rats in a house? Usually droppings or night time scratching noises. Rats are nocturnal and shy, so most people notice the evidence, droppings, gnaw marks or scurrying in the loft or walls, before they ever see the rat itself.
How can I tell if it is rats or mice? Size is the giveaway. Rat droppings are 9 to 14mm long, roughly the size of a grain of rice or larger, while mouse droppings are just 3 to 6mm. Rats also make louder scratching and scurrying noises and leave bigger gnaw marks.
Do rats come out during the day? Rats are mainly active at night. Seeing one in daylight usually means the nest is overcrowded, which points to a larger, well established infestation that needs professional attention.
Is one rat a sign of an infestation? Very often, yes. Rats live in groups and breed rapidly, so a single rat indoors usually means more are nearby. It is worth getting an inspection rather than assuming it is a one off.
Are rats in the house dangerous to my health? Yes. Rats can spread Leptospirosis (Weil’s disease), Salmonella and other illnesses through their urine and droppings, carry fleas and mites, and chew electrical wiring, which is a fire risk. Prompt removal is the safest option.
Can I get rid of rats myself? You can reduce numbers with traps, but DIY rarely finds the nest or blocks the entry points, so rats usually return. A professional treats the whole run and proofs your home so the problem does not come back.