The Top Carpenter Ant Signs to Look Out For

Not all ants are harmless. Some can cause real damage to your home—carpenter ants are one of them. In the Midwest, they’re a year-round problem once they move inside.

In this post, we’ll cover the top signs of carpenter ants, how they’re different from termites, and what to do if you suspect a carpenter ant infestation.

Key Takeaways

• Look for piles of sawdust (frass), hollow-sounding wood, and large black ants as warning signs.
• Seeing swarmers or hearing rustling noises in walls may mean a mature carpenter ant colony is nearby.
• DIY repellents rarely reach wall voids or crawl spaces where satellite nests are hidden.
• Professional carpenter ant control is the best way to get rid of these ants and prevent further damage.

Piles of Sawdust or Frass

One of the first signs of a carpenter ant infestation is frass—those tiny piles of sawdust and wood shavings left near baseboards, window sills, or even stumps around the yard. These aren’t just from chewing. Carpenter ants push the debris out of their tunnels as they carve through wooden structures to build their nests.

These piles of sawdust often show up in areas where you haven’t done any recent work, and they’re a big clue something’s tunneling through your home’s woodwork.

Rustling Sounds in the Walls

Hearing a faint rustling sound in your walls or ceilings? That could be worker ants. At night, when your home is quiet, you might pick up on rustling noises as these ants move through crevices in your walls.

This type of ant activity is one of those warning signs that often goes unnoticed until it becomes a bigger problem. Homeowners may even mistake it for rodents, but a thorough inspection from a pest control professional can help confirm the source.

Flying Ants Inside (Swarmers)

Swarmers are flying ants that appear when a carpenter ant colony has matured and is ready to spread. If you’re spotting these indoors—especially near light sources or along windows—it could signal the start of a larger infestation.

People often confuse them with termites, but there are differences.

Carpenter ant swarmers have a narrow thorax, elbowed antennae, and unequal wings. Termites have straight antennae and a thicker waist. Knowing which ant species you’re dealing with makes a big difference in treatment.

Damaged or Hollow Wood

Another major sign of carpenter ant damage is when wood sounds hollow or feels soft to the touch. This kind of structural damage is common when ants have been tunneling through for some time. You might find it around wooden supports, door frames, or flooring.

If you're seeing damaged wood, you could also be looking at a hidden carpenter ant nest in places like wall voids, crawl spaces, or other hidden areas of your home.

Large Black Ants, Especially at Night

Seeing large ants—usually black—in your kitchen or bathroom late at night? That’s another telltale sign. Carpenter ant workers are usually black and much bigger than other types of ants.

These ants are often spotted near sinks, dishwashers, or any areas with excess moisture. If you’re seeing regular ant trails or noticing them crawling out of cracks in the floor or walls, you may be looking at a growing ant problem.

What to Do About a Carpenter Ant Infestation

If you're spotting frass, hearing rustling, or seeing more black ants than usual, don’t wait. A growing carpenter ant infestation can lead to significant damage to your home’s woodwork and structural framing.

Many homeowners try DIY treatments or repellents, but those often only address surface-level ant activity. The real issue is deeper—inside walls, behind baseboards, and in hidden crawl spaces.

How Professional Pest Control Companies Can Help

At Miller Pest & Termite, we go beyond the surface. Our experts look for the core carpenter ant nest and any satellite nests that might be spread throughout the structure. We identify entry points, locate food sources, and use targeted strategies that reach deep into crevices and hidden spaces.

We never rely on just one method. Our pest management approach is customized to the specific ant species and layout of your home. And we don’t just aim to treat—we aim to prevent future infestations.

If needed, we’ll recommend sealing cracks with caulk and adjusting areas that might be attracting moisture or larvae development. We serve homeowners throughout Des Moines, Kansas City, and Omaha and bring years of pest control experience to every job.

Think you’ve got a carpenter ant infestation?

Call us today to schedule a free inspection with a trained exterminator. Let’s help you get rid of carpenter ants before they cause more damage than you bargained for.