Scratching in the Ceiling: Rats or Mice? | Go Green
Scratching in the Ceiling at Night: Is It Rats or Mice?
Heavy thumps, gnawing and running sounds in the ceiling at night usually mean rats. Light, fast pattering that comes and goes usually means mice. The surest way to tell is the droppings: rat droppings are about the size of a raisin, while mouse droppings are closer to a grain of rice. Either way, something has found a way inside, and it won't leave on its own.
How to Tell by the Sound
Rats are heavy enough that you can often hear them walking. Listen for thumping, dragging, and loud gnawing on wood or wiring. The noise tends to follow the same path each night, often along the edge of the ceiling or down inside a wall.
Mice sound lighter and quicker, like a soft scratching or tapping that moves around more. They are often busiest in the early evening and again before dawn.
Something else? Noise mainly at dawn and dusk can be squirrels. Very heavy movement at night can be a raccoon. Chirping and fluttering in the morning usually means birds nesting in a vent.
Rats vs Mice: Side by Side
Sign | Rats | Mice |
|---|---|---|
Droppings | 1.5 to 2 cm, thick with blunt ends | 3 to 6 mm, thin with pointed ends |
Sound | Thumping, dragging, loud gnawing | Light, quick scratching |
Entry gap | About the size of a quarter | About the size of a dime |
Damage | Large gnaw marks on wood, wiring and pipes | Small chew holes in food packaging and paper |
Other clues | Dark greasy rub marks along beams | Shredded nest material in corners |
How They Get Into the Ceiling
Rats and mice climb. Roof rats in particular run along fences, overhanging branches and power lines to reach the roof, then squeeze in through gaps at the soffits, roof vents or where the roofline meets the wall. Mice often start in the garage or crawlspace and travel up inside the walls. Gaps around plumbing stacks and cable entries give them a route between floors.
What You Can Do Tonight
Note where and when you hear the noise. That tells a technician where to start looking.
Check the attic hatch area and the garage for droppings, and take a photo with a coin next to them for size.
Trim branches that touch your roof and keep food, bird seed and pet food sealed.
Don't go into the attic and disturb droppings or nests without gloves and a mask.
When to Call a Professional
Call if the noise is there most nights, if you find chewed wiring, or if the droppings look like rat droppings. Rats in a ceiling can chew electrical wires, soil insulation and breed quickly, and their entry points are usually high up where they are hard to reach safely. An inspection finds the entry, removes the animals and seals the gap so the noise stops for good.
Ceiling Noises in Ladner and Tsawwassen Homes
Calls about noises in the ceiling go up in South Delta every fall, once the rain starts and rodents look for dry shelter. Homes with mature trees and hedges close to the roof, which is common in older parts of Ladner and Tsawwassen, give roof rats an easy way up. We serve all of Ladner, Tsawwassen and South Delta.
FAQ
Why do I only hear it at night?
Rats and mice are most active in the dark, and the house is quieter, so the sounds carry.
Can rats and mice live in the same ceiling?
It's uncommon. Rats prey on mice, so mice usually avoid areas where rats are active.
Will a cat or an ultrasonic device get rid of them?
Neither reaches rodents inside walls and ceilings, and neither closes the gap they came in through.
How do I stop mice getting in next fall?
Start with the entry points. Read How Mice Get Into Your House in Fall.
