Signs of carpenter ants in your home

Why carpenter ants are a concern for your home

Carpenter ants are one of the most common species of ants in North America, capable of causing significant structural damage if left unchecked. They don’t eat wood like termites, but they tunnel through it to build their nests, which can weaken the integrity of wooden beams, floors, and walls. Over time, this can lead to costly repairs and safety concerns. 

Understanding why these pests invade homes and recognizing the warning signs early can help prevent damage.

Common signs of carpenter ants in your house

One challenge with carpenter ants is that they often go unnoticed. They prefer damp or decaying wood, meaning you may not realize there's a problem until the infestation is well-established. That’s why knowing where to look and acting fast can help prevent costly repairs.

Piles of sawdust-like frass

Carpenter ants produce frass, which looks like sawdust. It’s made of wood shavings, insect parts, and debris they remove from tunnels. Unlike termites, which digest wood, carpenter ants discard it.

Frass often builds up near baseboards, under wooden furniture, or in crawl spaces. If you find small piles of powdery debris indoors, and there’s no clear source, it could mean an infestation. Sometimes, frass may also contain parts of dead ants, which is another clue that an active ant colony is nearby.

To locate the source of frass, check along walls, inside cabinets, and around wooden beams. If you see piles of frass near small openings around your home, you might have multiple carpenter ant colonies.

If frass continues to appear even after cleaning, it’s a sign that the ants are still actively tunneling. This means they are constantly working to expand their nest, potentially weakening the structure of your home.

Hollow-sounding or damaged wood 

Carpenter ants carve smooth tunnels inside wood. Over time, this can weaken structures, making them sound hollow when tapped. If walls, door frames, or furniture break easily or feel soft, there may be a colony inside.

Unlike termite damage, which is rough and packed with mud, carpenter ant tunnels are clean and polished. Use a screwdriver to check suspected wood—if it crumbles or feels hollow, ants may be nesting inside. The longer an infestation goes untreated, the more widespread the damage will become.

If you notice sagging or warped wooden structures, it could be a sign that carpenter ants have been tunneling inside for an extended period. Replace damaged wood right away, and contact a pest control expert to help prevent future problems.

Large, black ants inside or around your home 

Carpenter ants are some of the biggest household ants, measuring 1/4 to 1/2 inch long. Most are black, but some have reddish-brown coloring. Unlike most common smallerants, they prefer damp wood over food crumbs.

If you frequently see large ants, especially in kitchens, basements, or near windows, you may have a growing infestation. Even if you only see a few ants at first, it’s important to monitor their activity. Carpenter ants often have well-hidden nests, and spotting workers indoors could mean a larger colony is nearby.

During warmer months, carpenter ants may be seen traveling in and out of your home.If you see a line of ants on walls, baseboards, or tree branches, they are probably going from their nest inside to find food outside.

Rustling sounds within walls 

Carpenter ants are most active at night. As they tunnel, they can create a faint rustling or scratching sound. These noises are usually heard in quiet areas, especially near baseboards and window frames.

If you hear these sounds along with other warning signs, it may mean ants are inside your walls. Rustling noises usually mean ants are busy building a network of tunnels in your home. 

In severe infestations, these sounds may become louder, especially when the colony is disturbed. If you suspect an infestation, listen carefully at night when carpenter ants are most active.

Discarded wings near windows and doors 

During mating season, reproductive carpenter ants (swarmers) leave the nest to start new colonies. After mating, they shed their wings. You may find these small, translucent wings on windowsills, near doors, or around vents.

Unlike termite wings, carpenter ant wings are longer in the front than in the back. If you find wings indoors, check for other signs of infestation. Seeing swarmers indoors is a red flag and can suggest that a nest is already established within your home.

Finding discarded wings near window sills or on countertops is often one of the first visible signs of an infestation. Since swarmers are responsible for reproduction, their presence can indicate that the colony is growing and could soon expand to other parts of the home.

Where to look for carpenter ant activity

These ants like certain places for nesting. If you know where to look, you can find an infestation early, before it spreads. Carpenter ants like wood that is wet or rotting. This means any wooden structures, inside or outside, can attract them. 

Conducting routine inspections in these areas can help you identify a colony before it causes significant damage. You should regularly inspect the following areas for signs of activity:

Interior hotspots

• Baseboards, door frames, and window sills – These areas often have cracks where carpenter ants enter. Any small openings, gaps in the wood, or even minor damage can provide a way for these ants to move in and start tunneling.

• Kitchens, bathrooms, and basements – Moisture attracts carpenter ants, especially in areas with leaks or water-damaged wood. These rooms usually have plumbing, condensation, or high humidity. So, they make great nesting spots. Look for ants near sinks, inside cabinets, and along walls where pipes run.

Exterior trouble spots

• Decks, porches, and wooden fences – Outdoor wooden structures, especially those exposed to rain, are prime nesting locations.

• Tree stumps and landscaping timbers – Carpenter ants often begin their colonies in decaying wood before moving inside homes.

How to tell if you have carpenter ants or termites

Identifying the difference between carpenter ants and termites can be difficult because both pests can damage wood. While carpenter ants and termites can both weaken a home’s structure, their behaviors and the signs they leave behind are quite different. Incorrectly identifying these destructive pests can lead to ineffective treatments.

Here are two ways to determine whether you have termites or carpenter ants.

Differences in appearance and behavior

Carpenter ants and termites have distinct physical traits. Carpenter ants have segmented bodies with a narrow waist, bent antennae, and strong mandibles for chewing through wood. They are typically black or reddish-brown and range in size from 1/4 to 1/2 inch. In contrast, termites have straight antennae, a more uniform body shape, and are usually pale or light brown.

Behaviorally, termites consume wood as a food source, while carpenter ants do not eat wood—they excavate it to create nesting galleries. Termites tend to stay hidden inside the wood, whereas carpenter ants often leave their nests to forage for food. If you see large black ants inside your home, especially near food sources, you are likely dealing with carpenter ants rather than termites.

Comparing frass and wood damage patterns

Carpenter ant frass is made of tiny wood shavings and bits of insects. The ants push this material out of their tunnels through small holes, resulting in piles of sawdust-like debris near their nesting sites. Termite droppings, known as "frass," are more compact and pellet-like. Unlike carpenter ants, termites do not push their frass out but instead use it to build tunnels.

The damage patterns also differ. Carpenter ant tunnels are smooth, clean, and free of debris because they carve the wood carefully. Termite tunnels, on the other hand, are rough and filled with mud, as termites use soil and saliva to reinforce their galleries. 

If you notice polished, sanded-like tunnels inside damaged wood, carpenter ants are likely the cause. If the tunnels are packed with dirt, you may have a termite infestation.

What to do if you see signs of carpenter ants

If you suspect carpenter ants in your home, it’s important to act quickly before the problem worsens. Carpenter ants are also known for expanding their colonies over time. 

A small satellite colony in your home can expand into a large network of nests. This growth can cause even more damage to your structure. The sooner you take action, the easier it will be to help prevent serious structural issues.

DIY steps to confirm an infestation

If you suspect a carpenter ant infestation, confirming their presence is the first step. Here are some ways that can help indicate if carpenter ants are present:

• Look for piles of frass and damaged wood. Carpenter ants push out wood shavings as they tunnel, leaving small piles of sawdust-like material near their nests. If you spot this near baseboards, door frames, or wooden furniture, it’s a strong sign of an infestation.
• Tap on wood to check if it sounds hollow. Since carpenter ants carve smooth tunnels inside wood, they weaken structures over time. Tapping on suspected areas can help determine if the wood has been hollowed out.
• Use bait to track ant activity. Setting out sugary or protein-based bait can attract foraging ants, helping you locate high-traffic areas. However, killing the ants you see won’t eliminate the colony, as the queen and workers remain hidden deep inside wooden structures.

These ants usually stay hidden in walls or wooden structures. This makes it tricky to find them without close observation. If you suspect carpenter ant activity, it is crucial to contact a professional exterminator.

Why professional carpenter ant treatment is the best solution

Professional carpenter ant treatment is the most effective way to eliminate an infestation and prevent future damage. Unlike DIY methods that only deal with visible ants, our ant control technicians can find and help eliminate entire colonies.

Need help with carpenter ants? Contact us today

At Western Exterminator, our team of experienced professionals knows exactly how to help locate carpenter ant nests, eliminate them at the source, and implement preventive measures to keep them from coming back. 

Our experts will assess your situation, create a customized treatment plan, and provide you with peace of mind. Contact us today to get started.

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