What’s That Sound? The Most Common Culprits That May Be Hiding in Your Walls

You hear a faint, unsettling scratch, scratch, scratch coming from inside your walls. It might sound like the start of a horror movie, but in reality, it could be a sign of an infestation.

Mysterious scratching, rattling, or buzzing sounds can have several explanations. Sometimes, it’s as harmless as a tree branch brushing against your house in the wind or the natural creaks of a settling home. However, those sounds may also signal the presence of pests lurking inside your walls.

What Types of Pests Might Be In Your Walls?

According to Morgan Roberts, owner of Morgan’s Pest Management in Sherwood, Oregon, there are several usual suspects that could be lurking in your walls. “Oftentimes the culprit for scratching in the walls are critters such as rodents, squirrels, or even some insects,” Roberts shares.

Roberts says to determine what type of creature it could be, pay attention to the time of day you hear the noise. Rodents are most active in the evening and overnight, while squirrels tend to be active during the day. Let’s explore each of these unwanted visitors and their habits to help better pinpoint the sounds you’re hearing.

Rodents

Rodents such as mice and rats are common intruders in crawlspaces, attics, and walls. They are likely seeking warmth, food, and shelter. If you hear scratching, gnawing, or scurrying sounds coming from inside your walls, especially at night, there’s a strong possibility of a rodent infestation. Beyond the noises, rodents leave behind other telltale signs. 

Signs of a Rodent Infestation

• Droppings – Small, dark, pellet-shaped droppings found in corners, along baseboards, or near food sources.
• Gnaw Marks – Rodents can chew through wood, drywall, wires, and even plastic to create entryways or access food.
• Grease Trails – Rodents leave greasy smudge marks from their fur as they move through tight spaces.
• Nesting Materials – Shredded paper, fabric, or insulation in hidden areas indicate nesting activity.

How to Handle a Rodent Infestation

While contacting a pest management professional like Morgan’s is a reliable solution, there are several steps that you can take to prevent and control the problem.

• Seal Entry Points – Inspect your home’s foundation, roof, and exterior walls for small gaps or holes, especially around utility pipes and vents. Use steel wool, caulk, or metal mesh to block potential entryways.
• Eliminate Food Sources – Store food in airtight containers, clean up crumbs and spills promptly and avoid leaving pet food out overnight.
• Declutter and Remove Nesting Materials – Reduce clutter in attics, garages, and basements, as rodents prefer hidden nesting spots.
• Use Traps and Bait Stations – Snap traps, glue boards, and bait stations can help reduce rodent populations. Place them along baseboards, near entry points, or where signs of activity are found.
• Maintain Proper Sanitation – Regularly clean floors, pantries, and storage areas to deter rodents.

A proactive approach to rodent control can help prevent significant damage to your home and potential health risks, as rodents are known carriers of diseases and can chew through electrical wiring, increasing fire risk. If the problem persists, professional extermination services may be necessary to fully eliminate the infestation and give you peace of mind. 

Squirrels

Squirrels are agile and resourceful creatures that can easily access attics, walls, and crawlspaces by squeezing through small gaps or gnawing their way inside. Once they settle in, they can cause significant damage to insulation, electrical wiring, and wooden structures. Unlike rodents, squirrels are diurnal, meaning they are most active during daylight hours. If you hear scratching, thumping, or rapid scurrying noises in the morning or late afternoon, squirrels may very well be the culprits.

Signs of a Squirrel Infestation

• Daytime Noises – Listen for loud scrambling, scratching, and scurrying sounds, especially in the early morning or late afternoon.
• Chewed Entry Points – Squirrels can gnaw through wood, soffits, and plastic vent covers to create access points.
• Nesting Materials – Shredded insulation, leaves, or twigs found in your attic or near entry points may indicate a nest.
• Droppings – Squirrel droppings are larger than those of mice and usually oval-shaped with rounded ends.
• Unpleasant Odors – A trapped or dead squirrel inside your walls may produce a strong, foul smell.

Preventing a Squirrel Infestation

• Inspect and Seal Entry Points – Check for gaps or holes along the roofline, soffits, vents, and chimneys. Seal any openings larger than two inches using metal flashing or heavy-duty wire mesh.
• Trim Overhanging Tree Branches – Trim back branches that hang too close to your roofline (at least 6-8 feet away).
• Use Squirrel Deterrents – Motion-activated lights or ultrasonic repellents can help discourage squirrels from nesting.
• Secure Outdoor Food Sources – Avoid leaving pet food outside, secure trash bins with tight-fitting lids, and remove bird feeders.
• Install Chimney Caps and Vent Covers – Durable covers can prevent squirrels from entering through uncapped chimneys or open vents.

How to Handle a Squirrel Infestation

If you suspect squirrels have already moved in, avoid sealing entry points until you’re sure they’re gone. A few removal strategies include:

• One-Way Exclusion Doors – Allow squirrels to leave but prevent them from re-entering.Live
• Trapping – In some cases, live traps baited with nuts or seeds can be effective, but check local wildlife regulations before attempting relocation.
• Professional Wildlife Removal Services – A licensed expert can safely trap and relocate them without harming the animals.

By taking proactive steps to squirrel-proof your home, you can prevent these energetic rodents from causing costly damage.

Bats

Bats are beneficial creatures that play a vital role in controlling insect populations, but when they take up residence in your home, they can become a serious nuisance. If you hear fluttering, rustling, or light scratching sounds around dusk or dawn, it may indicate a bat infestation in your attic, walls, or chimney. These nocturnal mammals emerge at night to hunt for insects, returning to their roosts before sunrise.

Bats typically seek shelter in homes during the late fall as temperatures drop. They are drawn to attics, wall voids, and other secluded spaces offering warmth and protection from predators. Once inside, bats may establish a colony, which can grow over time if left unchecked.

Signs of a Bat Infestation

• Seal Entry Points – Check for small gaps or cracks around vents, chimneys, soffits, and rooflines.
• Install Chimney Caps and Vent Covers – Secure them with durable mesh or metal covers.
• Eliminate Drafts and Gaps in Rooflines – Repair loose shingles or other structural openings.
• Use Bat Deterrents – Motion-activated lights, ultrasonic repellents, or reflective surfaces can discourage bats.

How to Handle a Bat Infestation

Since bats are protected by law in many areas, their removal must be handled carefully.

• One-Way Exclusion Devices – Allow bats to exit but prevent them from returning. This method is most effective when installed in late summer or early fall.
• Professional Bat Removal Services – A licensed expert can assess the situation and implement a safe, legal removal plan.
• Do Not Seal Entry Points Immediately – Avoid sealing openings while bats are inside, as this could trap them.

A bat infestation can lead to serious health risks. Those health risks include histoplasmosis, which is a lung infection caused by inhaling fungal spores from bat droppings, or guano. Bats also can carry rabies. If you find a bat inside your home, never handle it with bare hands. By identifying the problem early and taking appropriate steps, you can prevent bats from turning your home into their roosting ground while ensuring their humane removal.

Birds

Certain species of birds can become unwelcome guests when they invade your walls, attic, or the exterior of your home. Some birds, like starlings, seek out small, enclosed spaces for nesting, while others, like woodpeckers and flickers, may peck holes in your siding in search of food or to establish a nesting site. Identifying the type of bird activity can help determine the best course of action for removal and prevention.

Signs of a Starling Infestation

• Listen for Sounds – Chirping or scratching sounds may be heard inside walls, particularly in spring and summer.
• Droppings – Look for bird droppings accumulating near entry points.
• Nesting Materials – Look for twigs, leaves, or feathers found in or near vents and rooflines, and blocked vents or gutters due to nesting materials.

How to Prevent and Remove Starlings

• Look for Entry Points – Seal entry points with heavy-duty wire mesh.
• Install Covers – Install vent covers to prevent nesting inside ducts. Cover affected areas with bird netting or plastic sheeting.
• Clear Nests and Debris – Remove existing nests (if no eggs or hatchlings are present) and clean the area thoroughly.
• Get Bird Repellants – Install visual deterrents like reflective tape or owl decoys. Apply non-toxic bird repellents on affected surfaces. Or use noise deterrents like distress calls or predator calls.
• Get a Professional – Call a wildlife control specialist if they have nested inside your walls.

Signs of Woodpecker or Flicker Damage

Unlike starlings, woodpeckers and flickers do not typically nest inside walls but cause damage by drilling holes into wood siding, stucco, and metal surfaces.

• Look for the Holes – Look for multiple small holes in wooden siding, often arranged in rows or larger single holes used as nesting sites.
• Listen for Sounds – Constant tapping or drumming sounds, especially in the early morning, are often heard.
• Check out for Shavings – Wood shavings may be seen around the base of your home.

How to Prevent and Remove Woodpeckers and Flickers

• Install Covers – Install vent covers to prevent nesting inside ducts. Cover affected areas with bird netting or plastic sheeting.
• Get Bird Repellants – Install visual deterrents like reflective tape or owl decoys. Apply non-toxic woodpecker repellents on affected surfaces. Or use noise deterrents like distress calls or predator calls.
• Look for Bugs – Check for carpenter ants, termites, or other insects they may be hunting.
• Get a Professional – Call a wildlife control specialist if they have nested inside your walls.

While birds may not seem as destructive as rodents or insects, they can still cause significant issues, including structural damage, health risks, and more

Yellowjackets, Bees, and Hornets

According to Morgan Roberts, “Less commonly, yellowjackets, bees, and hornets can create buzzing or scratching noises within the walls, but insects are less common in the walls.” While some homeowners initially mistake these sounds for electrical issues or rodent activity, a closer listen may reveal the distinct hum of an active hive.

Signs of a Yellowjackets, Bees, and Hornets Infestation

• Buzzing Noises – The hum of a growing hive can often be heard, particularly at night when the house is quiet.
• Scratching or Chewing Sounds- Yellowjackets have been known to chew through drywall and insulation to expand their nest.
• Increased Insect Activity – A sudden surge in wasps or bees around vents, rooflines, or siding could indicate an indoor colony.
• Visible Entry Points – Look for small holes or cracks in exterior walls, soffits, or eaves where insects enter and exit frequently.
• Discoloration on Walls or Ceilings – Severe cases may show soft spots, bulging, or even honey seepage from bees.

How to Handle a Yellowjacket, Bee, or Hornet Infestation

Attempting to remove a wasp or bee nest from within your walls can be extremely dangerous. Agitating the hive can cause the colony to swarm, increasing the risk of multiple stings. Additionally, improper removal can leave behind honey or nesting materials, attracting new pests.

• Contact a Licensed Pest Control Service – Professionals have the proper protective gear and techniques to safely remove nests.
• For Honeybees, Call a Beekeeper – Many local beekeepers offer live removal and relocation services.
• Seal Entry Points After Removal – Prevent reinfestation by sealing off openings and reinforcing vulnerable areas.

Conclusion

Roberts underscores the significance of vigilance in safeguarding your home’s condition as your first line of defense. “If you find yourself hearing any strange noises like scratching, thumping, rattling, or buzzing in your walls, you’ll want to evaluate your home’s condition and any possible conducive environments,” he says. Regularly inspect crawlspace screens, vents, and the integrity of door sweeps and garage seals, as contractors may unintentionally create access points during repairs.

In addition, managing attractants, such as bird feeders, compost piles, and wood stacks, can significantly deter rodents from taking up residence on your property. By implementing these proactive measures, you can enhance the protection of your home against unwanted pests.

Staying informed about seasonal pest behaviors and trends can further empower you in your preventive efforts. Understanding that certain pests may be more active during specific times of the year allows you to anticipate potential issues and take action before they escalate. Regular communication with pest management professionals can also provide valuable insights and tailored advice for your unique situation, ensuring your home remains a safe and comfortable place for you and your family.