Rats inside walls create a range of distinct sounds that you can often use to tell if you have an infestation. The most common noises include scratching, scurrying, gnawing, squeaking, and thumping. These sounds are the direct result of rats moving, nesting, eating, and communicating. The noises tend to be most noticeable at night, when rats are most active.

Types of Rat Noises and What They Mean

• Scratching: The most common noise. Rats use their claws to climb, burrow, and build nests within insulation or other materials inside the walls. The sound is a rapid, light scratching or scraping that repeats as the rat moves or digs.
• Scurrying or rushing: As rats run along wall cavities, especially when startled, you may hear a soft, quick pattering sound. This can move from one end of the wall to another and sometimes between floors, as rats are skilled climbers.
• Gnawing: Rats constantly chew to keep their teeth from growing too long. When they gnaw on wood, drywall, plastic, or metal pipes, the noise is a steady, repetitive crunching or grinding — sometimes quite loud for their size.
• Squeaking and chattering: Rats use high-pitched squeaks, squeals, or rapid clicking to communicate. While less obvious than movement sounds, in quiet environments you may still hear them.
• Thumping or bumping: If rats are running, fighting, or jumping within wall voids, you may hear dull thuds or bumps. These indicate a higher level of activity or multiple rats inside the walls.

How Rat Sounds Differ from Mouse Sounds

Rat sounds in walls are distinctly heavier and louder than mouse sounds:

• Mice — rapid, light scurrying (like fingers tapping quickly)
• Rats — slower, heavier thumping (like someone dragging a soft object)

Rat gnawing is also deeper and more sustained than mouse gnawing. If the sound wakes you up or is clearly audible from another room, it's more likely rats than mice.

Where You Hear the Sound Matters

The location of noises helps identify the species and where they're traveling:

• Sounds near the floor or under floorboards = Norway rats burrowing (common in NH)
• Sounds in walls at mid-height = rats traveling between floors through wall voids
• Sounds in ceilings or upper walls = roof rats (uncommon in NH but possible)
• Sounds in basement ceiling = rats in the crawl space above the slab

In New Hampshire, Norway rats are by far the most common species in walls. Unlike roof rats, Norway rats don't typically enter attic spaces — if you hear sounds exclusively in your attic, you more likely have mice or squirrels.

When and Where Are Noises Most Noticeable?

Rats are nocturnal — most active from dusk until dawn. You're most likely to hear these sounds late at night or early in the morning when the house is quiet. Sounds often come from floor-level or ceiling-level walls, attics, crawl spaces, or behind appliances and cabinetry that connect to wall voids.

Why You Should Pay Attention to These Noises

If you hear these noises repeatedly, particularly at night, it's a strong sign that rats may have nested or are traveling within your walls. Ignoring these sounds can lead to bigger problems — rats chew through wiring (creating fire hazards), damage insulation, and spread disease. Early identification is crucial for effective pest control. If you're unsure, record the noises and contact Anchor Pest Services at (603) 785-0118 for a professional assessment across New Hampshire.

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