Tapping Sound in Wall: Is It Pests, HVAC, or Something Else?

Are strange sounds coming from your walls driving you crazy? If tapping, scratching, or scurrying noises keep you wondering what is causing them at night, this blog post has the answers. We’ll explore common causes of these puzzling noises and provide helpful advice on pinpointing the source to take action and end it. From pesky pests, plumbing issues & HVAC problems to structural concerns – don’t let those mysterious wall tappings remain a mystery any longer! Read on for everything you need to know about odd household happenings.

Causes of Tapping in Walls



Rodents like squirrels, raccoons, chipmunks, mice, and rats can cause tapping and scratching sounds as they move through walls and ceilings. They gain access to a house by squeezing through small openings like gaps in the foundation or holes in walls/ceilings. Rodents create nesting sites by gnawing through drywall, wood, and other building materials. Not only can this cause damage to the insulation and electrical wiring, their droppings, urine, and nesting material attract pests and pose health hazards.


Carpenter ants

An insect infestation, such as termites or carpenter ants, can cause tapping sounds in walls. These insects tunnel through wood and eat away, weakening the home’s structure. Termites are often found in warm, moist climates and near wood that is in contact with the soil. Carpenter ants typically inhabit damp or rotting wood and homes with leaky roofs or plumbing. Both insects can cause costly structural damage if left unchecked. Signs of infestation include tapping sounds in walls, as well as sawdust or discarded wings.

Pests that could be making tapping noises

  • Mice – You may hear mice chewing or moving their food within your wall. If you hear a faint “tap tap tap” noise accompanied by the sound of scraping, chances are that there may be mice in your walls. You might also hear chirping and slight rustling. Because of their territorial nature, mice can sometimes be heard scurrying about as they compete for space. You might also hear squeaking, especially if there are younger mice present.
  • Chipmunks – Chipmunks, unlike many other pests, are diurnal as their eyes are not well-equipped for night vision. That said, they can still see in the dark, a skill that allows them to inhabit walls for short periods. While chipmunks typically enter a building structure at or below the foundation level, it is not uncommon to find them hiding or climbing in gutters, consequently causing loud scratching sounds.  You may also hear tapping in your walls as chipmunks hide their food in wall voids and dart in and out of their temporary habitat.
  • Rats – Rats are quieter than chipmunks, but you may hear rustling as they move around in wall voids. They also make squeaking noises, and as they become accustomed to their habitat in the wall, you may even hear chewing sounds. If the chewing is especially extensive, arcing wires may emit a tapping sound, indicating a possible electrical malfunction.
  • Raccoons – In case a raccoon finds its way into the void in your wall, you are bound to hear a lot of noise from their movements. Apart from the standard tapping, chances are that you will also hear hissing, scratching, and even crying sounds in some cases. Skunks also typically make similar sounds when trapped in a wall void and emitting a pungent smell.
  • Bats – Bats are commonly known for getting into attics, although it is not unheard of to find some living in wall voids. Bats can squeeze through small openings in soffits, behind shutters, and around chimney flashing, among other areas. During the summer, bats prefer to roost in sheltered locations – ridges and rafters in attics serve as ideal roost locations. If the infestation is particularly large, some bats can roost in wall voids, especially if structures can support them.

During colder months, bats typically migrate to environments with stable temperatures, such as caves and hollow trees. Attics also seem to provide the insulation they need during this period, so you may often find them hibernating in homes. If there is a sudden temperature increase and the bats awaken, you may hear tapping and scratching in your wall as they crawl around, often accompanied by squealing.

  • Squirrels – Squirrels cause quite a ruckus when trapped in walls. Flying squirrels are particularly active before dawn and shortly after dusk, and you can often hear them carrying food into the house. They usually set apart an area they use for sleeping and a dedicated latrine, which can get quite stinky over a long period and cause stains to develop on your wall.

Gray and red squirrels are diurnal, returning to their makeshift nests in wall voids at night. Their teeth can be heard making chewing noises as they chow down nuts, whereas their claws tend to make scratching sounds.

  • Termites – Despite their size, termites can create an ever so slightly audible tapping sound if they find their way into your wall. This is true, especially when you consider the fact that they tend to live in large colonies. Formosan termites, in particular, are known to make a slight tapping sound, especially if they are disturbed.
  • Carpenter ants are nocturnal creatures and can get quite noisy at night. Each leg on a carpenter’s ant features four hooks at the end, allowing the critter to hold fast onto various surfaces. A scratching and soft tapping can be heard as these ants move within the wall.

Although carpenter ants don’t feed on wood, they hollow it out to create nesting galleries. As the wood is continually thinned out, noise from their movements is amplified. If the infestation in your walls is especially severe, the noise can be audible from quite a distance.

  • Wasps – The species of wasp commonly known to nest in wall voids is the yellow jacket. Yellowjackets typically make their way into homes through small holes that may be present in the foundation and siding and through cracks and crevices in the attic. Once they become established, yellow jackets will continue to grow their nests; after some time, the nest material could fill several voids in your walls. As worker yellow jackets move about in the wall, you can hear scratching, tapping, and buzzing.
  • Deathwatch beetles – Deathwatch beetles emit a slight tapping sound as they emerge from wood to attract the attention of the opposite sex. Other wood-boring beetles, such as the Old House borer and the New House borer, can also emit a tapping sound as they move through wood.


Plumber working

Tapping sounds in walls can be caused by plumbing issues such as leaks, loose pipes, and uninsulated pipes. Leaks can cause tapping sounds as water drips onto a hard surface inside the wall. Loose pipes may create a tapping noise when water is flowing through them. Lastly, uninsulated pipes may expand and contract with temperature changes, resulting in a knocking sound.

HVAC issues

HVAC technician working

Potential causes of tapping sounds in walls may include issues with the heating, ventilation, and air conditioning (HVAC) system. Loose ductwork can cause a rattling or tapping sound as the air passes through it. Additionally, insufficient maintenance of an HVAC system can lead to dirt, debris buildup, decreased airflow, and strange noises. Worn-out parts in an aging HVAC system can also cause tapping or rattling sounds. Proper HVAC system maintenance and inspection is essential to avoid such issues.

Structural issues

Crack in the wall

Tapping sounds in walls can be caused by structural issues such as settling foundations or framing problems. These can cause the house to shift or move due to natural settling, weather changes (e.g. heavy rain, snow, wind) putting extra stress on the structure, creating tapping or creaking noises. The foundation can misalign the walls and generate tapping or rattling sounds if the foundation settles. Damage or weakness in framing can also cause the walls to move, creating tapping sounds. Identifying and addressing structural issues is essential to reduce or eliminating these types of noises.

How to Determine the Cause of the Tapping

Inspection of the home

Home inspection

A home inspection is essential in determining the cause of sound tapping in walls. By inspecting the home, you can look for any signs of pests, such as droppings or gnawed wood, and any leaks or damage to pipes and ductwork that could be causing the noise.

Additionally, by noting any unusual vibrations or noises, you can pinpoint the location and source of the tapping.

For example, suppose a specific area has droppings or gnawed wood present. In that case, it may indicate a pest infestation, and further inspection will focus on identifying the type of pest and its entry points.

On the other hand, if a tapping or dripping sound is coming from a particular area, it may indicate a plumbing issue. The inspection will focus on identifying the source of the leak and any damage to the pipes.

It’s also important to check for any structural integrity issues in the home, like cracks on the wall, addressing them as soon as they are identified. Additionally, ensure that proper insulation is present and that all pipes and ductwork are properly installed and secured to prevent future issues.

Consultation with a professional

Consulting with a professional

Consulting with professionals can help homeowners better understand the problem and determine the best action to fix it.

  • An exterminator can identify pest infestations and recommend extermination and prevention measures.
  • A plumber can check for leaks or damage to pipes and provide repair recommendations.
  • An HVAC technician can inspect and repair the air conditioner and ensure that ducts are adequately sealed.
  • A structural engineer can assess the house’s foundation and framing and ensure necessary repairs are done correctly to fix the issue.

By consulting with experts in various fields, homeowners can be sure that they get accurate and reliable information about the problem and cost-efficient solutions that solve it most effectively. This can save time and money in the long run.

Utilizing technology

Endoscopic camera

Utilizing technology can also help determine the source of tapping sounds in walls. Various tools and equipment can be used to inspect the home and identify the cause.

  • Acoustic vibration sensors or sound level meters can detect high-pitched noises within walls, which may indicate the presence of pests such as termites.
  • Endoscopic cameras can be inserted into walls or other tight spaces to inspect the inside of the walls and ducts, helping identify any issues, such as pests or structural damage near wires, that could be causing the tapping.
  • Thermal imaging cameras can also detect temperature differences in the walls, indicating water leaks or other sources of moisture.
  • Moisture meters can detect moisture, which can help pinpoint the location and source of tapping sounds.

By utilizing technology, homeowners can get a more accurate and detailed understanding of the problem and make informed decisions about how to fix it. It can also help to speed up the diagnosis process and make repairs more efficient, saving time and money.

It’s important to use equipment of good quality and have the proper training to use it. It’s also essential to consult with a professional to ensure that the equipment is properly calibrated and that the results are accurate.

How to Fix Tapping in Walls

Pest control

Pest control

Pest-caused tapping sounds in walls can be a worrying experience for homeowners. To fix the issue, pest control must identify and eliminate the pests and seal any entry points they are entering the home.

  • If rodents are identified as being the cause of the tapping sound, extermination options such as traps, bait, or pesticides can be used to get rid of them. Once the pests are eliminated, it’s important to seal any entry points, such as gaps in the foundation, holes in walls and ceilings, or openings around pipes or vents.
  • For insects like termites and carpenter ants, an exterminator will identify the type of insects and the extent of the infestation, then use appropriate treatment methods such as pesticides or baits to eliminate them. Additionally, they will identify the source of the moisture that attracted the insects to prevent future infestations.

It’s important to remember that pest control is a process that requires multiple steps and regular monitoring. After the pests are eliminated, scheduling follow-up inspections are important to ensure they do not return.

Plumbing repairs

Plumber technician working

Plumbing issues such as leaks or loose pipes can cause tapping sounds in walls. To fix this problem, a plumbing repair is necessary.

  1. The first step is to identify the source of the problem. This can be done by visually inspecting the pipes for any damage or using specialized tools such as a pipe camera to locate any hidden issues.
  2. Once the source of the tapping is found, a qualified plumber can make the necessary repairs.
  3. If it’s a leak, it could involve replacing a damaged pipe or tightening any loose fittings.
  4. Securing them with straps or hangers and adjusting insulation may be required for loose pipes.

It’s important to hire a qualified plumber to ensure the plumbing repairs are done correctly and help avoid any future costly repairs.

HVAC repairs

HVAC technician working

HVAC systems regulate indoor temperature and air quality but can also be the source of sound tapping from walls. To fix this issue, a qualified HVAC technician must identify and repair the source of the problem.

  • For example, loose ductwork is a common cause of tapping noises, so the technician will start by locating the loose ducts and securing them in place. This can involve tightening the fasteners or replacing damaged sections of ductwork. In addition, they’ll check for proper insulation and adjust it if needed.
  • On the other hand, if the cause is a poorly maintained HVAC system, the technician will first inspect it to identify any issues, such as a buildup of dirt and debris, worn-out parts, or leaks. Then, they will perform the necessary maintenance, cleaning, and repairs to ensure it’s running smoothly and quietly.

Hiring a qualified HVAC technician for these jobs is essential as they are often complex tasks. Regular maintenance and cleaning can help homeowners avoid bigger issues and costly repairs in the future.

Structural repairs

Repairing wall

Tapping sounds in walls can be caused by structural issues, such as settling foundation or framing problems. If you’re experiencing these sounds, it’s important to identify the source of the problem and make the necessary repairs.

  • For example, if the cause of the tapping sound is a settling foundation, a structural engineer will assess the foundation and determine the best course of action to fix it. This could include underpinning or installing piers to support the foundation and stop it from settling further.
  • If framing problems are causing the tapping sound, they will inspect the framing and identify any issues, such as rot or damage caused by pests or weather. Then, they will repair or replace the damaged framing members to ensure that the house is structurally sound.

It’s important to note that structural repairs can be complex and may require a qualified structural engineer to ensure the repairs are done correctly. Regular maintenance and inspections of your home can help prevent bigger issues in the future and save you from costly repairs.


In conclusion, tapping sounds in walls can be caused by various issues, such as pests, plumbing, HVAC, or structural problems.

To accurately identify the source of the problem and take appropriate action steps to fix it, homeowners should consider inspecting their home themselves, consulting with professionals for advice, utilizing technology for detection methods if necessary, engaging in pest control procedures, making plumbing repairs as needed, performing HVAC repairs if applicable, and addressing structural problems.

It is essential to address the issue promptly to avoid further damages and costly repairs. Additionally, regular maintenance through inspections can help prevent bigger issues from arising. These steps can help homeowners regain control of the situation and have peace of mind.

Related article:

Why Do Pipes Make Noise?

How Do You Know if a Squirrel is in Your Wall?

How Do You Tell If There Is An Animal In Your Wall?

Can My Neighbors Hear Me In My Apartment?

Clicking in the Walls: Is It Harmless or a Serious Problem

What Are Quiet Times in Apartments?

Zoltan Szatmari

Zoltan is a test and industrial engineer from Europe who loves learning anything new and working on small projects. When he is not working, he is usually hiking or going to the cinema.

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