How to Get Rid of Carpenter Ants in the House

Indoor Baiting

Baiting is one of the most effective strategies, especially when colonies are concealed or inaccessible. The toxic bait is carried back to the nest, spreading poison throughout the colony.

Pesticide Treatments

Pyrethrin-based pesticides are derived from chrysanthemum flowers and work by paralyzing and killing ants. Locate the nest, drill small holes, and inject spray directly into the colony.

Diatomaceous Earth

D.E. is a natural substance that dehydrates ants by breaking down their exoskeleton. It is completely organic and safe to use around the home.

Find and Remove the Nest

Carpenter ants nest in soft, decaying wood found in wood piles, dead tree stumps, lumber debris, sheds, patios, decks, and footings. Remove decaying wood and replace with sound material. Address moisture sources to prevent rot.

Outdoor Baiting

Use the same bait strategy around your home's perimeter and near potential nesting sites like tree bases, firewood piles, or stumps. Place bait heavily along identified ant paths. Use tamper-proof stations if you have pets or children.

Non-Repellent Sprays

Products like Termidor SC remain active for years. Apply around the foundation and suspected ant trails. Non-repellent sprays allow ants to carry insecticide back to the colony, affecting the entire nest.

Direct Dusting

When you have access to the nest, use specialized insecticide dust to target and kill carpenter ants rapidly. Use a duster to reach deep into the nest, contacting the queen and entire colony.

Boric Acid Treatments

Mix boric acid with powdered sugar (1/3 sugar to 2/3 boric acid). Place in bottle caps where ants are active. Workers carry bait back to the nest. Can take several weeks but is powerful. Borax is a natural, non-toxic alternative.

Professional Pest Control

If DIY methods are not resolving the problem, professional services offer tailored solutions, thorough treatment, and ongoing monitoring. Many companies offer year-round protection subscriptions.

Carpenter Ants

• Do NOT eat wood
• Tunnel through wood to create nests
• Leave fine wood dust (frass)
• Narrow, constricted waist
• Jointed (elbowed) antennae
• Wings shorter relative to body

Termites

• Actually EAT wood
• Cause far more extensive damage
• Create rough, dirty tunnels
• Cylindrical body shape
• Straight antennae
• Longer wings relative to body

Piles of Sawdust (Frass)

Carpenter ants excavate wood by shredding tiny pieces with their mandibles. This results in small piles of wood shavings near entry points or below wooden structures.

Wood Damage

Look for smooth, clean tunnels within wood. Unlike the ragged, dirty tunnels created by termites, carpenter ant galleries are polished and free of debris.

Rustling Sounds

At night, you might hear a faint rustling or crackling noise within the walls. This sound comes from carpenter ants gnawing on the wood.

Worker Ants

Seeing large, black or dark brown ants around moist or damp wood is a strong indication. These foraging ants can lead you back to their nest.

Swarmer Wings

During spring and early summer, you might find discarded wings near windowsills, doors, or entry points. These belong to reproductive ants starting new colonies.

Small Holes in Wood

Discovering tiny, round holes in wooden structures can indicate carpenter ants. These holes are used to eject wood debris from their nests.

1. Inspect Damp Areas

Carpenter ants are drawn to moist, decaying wood. Check areas with water leaks like bathrooms, under sinks, and around window and door frames.

2. Check Wood Damage Areas

Look for small holes in wood and piles of fine sawdust or frass. These are typically found near entry points to the nest and indicate tunneling activity.

3. Follow Ant Trails

Carpenter ants leave pheromone trails. Track these along baseboards, cabinets, doors, and wooden structures back to their origin. Be patient; they may lead to hidden nests.

4. Listen for Sounds

Carpenter ants create rustling noises within walls. Tap your walls to identify hollow spots that may house a nest. This helps pinpoint the exact location.

5. Use Bait to Lure Them

If ants are elusive, set up bait stations with diluted honey or sugar milk. Since carpenter ants are most active at night, check traps after dark to discover their nest.

Fix Moisture Issues

Carpenter ants are attracted to damp wood. Repair leaks in plumbing or roofing that cause moisture buildup. Ensure proper ventilation in crawl spaces, attics, and basements.

Seal Entry Points

Use silicone caulk to seal cracks and crevices around your home's foundation, doors, and windows. This blocks potential entry points for ants.

Remove Clutter and Wood

Dispose of old wood piles, dead tree stumps, and potential nesting materials. Store firewood away from your home and off the ground.

Maintain Cleanliness

Carpenter ants still seek food that normal ants eat. Clean up crumbs and spills immediately, store food in sealed containers, and take out trash regularly.

Prune Trees and Bushes

Trim branches and shrubs that touch your house to prevent ants from using them as bridges to enter your home.

Eliminate Scent Trails

Mix one part liquid dish soap with two parts water. Spray over pheromone trails to erase the ants' path and discourage them from coming back.