How to Get Rid of Carpenter Ants In The House

Carpenter ants are common structure-infesting ants found throughout Canada. These tiny insects primarily live outdoors, but gain access to homes when looking for food sources and sites to establish satellite nests.

The issue with carpenter ants is that they can cause structural damage to a home. The damage caused by carpenter ants usually manifests in the declined structural integrity of joists, trusses, support beams and the overall foundation of a home. Carpenter ants dig elaborate systems of tunnels into wood within homes and outdoors, which are recognizable by piles of removed saw-dust like debris at tunnel entrances and exits. Homeowners will generally see the large worker ants of carpenter ant colonies first. The large, wingless ants act as scavengers and often report back to their respective colonies about food sources. As such, worker ants seen in the home may not necessarily signal an infestation but rather the possibility of one as sightings clearly indicate viable access points for the species of ant.

Carpenter Ants vs. Other Black Ants

Not sure if you’ve got other ants or carpenter ants in your home? Carpenter ants are larger than most ants, and are usually black or red. Unlike most ants, carpenter ants also have the ability  to chew and tunnel through wood. Learn more about what carpenter ants eat.

How Do Carpenter Ants Get into a Home?

There are a variety of places within a home where carpenter ants can enter. 

Kitchens and other areas of the house where meals are held serve as common draws to carpenter ants.  Carpenter ants can enter houses through bathrooms, roofs or basements where leaky pipes and general moisture soften baseboards and other access points so that ants can dig or excavate to invade. They also crawl along and through utility lines, via shrubs or tree branches touching houses. Once indoors, carpenter ants can establish nests in wall voids, attics, insulation, crawlspaces, etc. A carpenter ant is  capable of burrowing through sound wood, but prefers softer, water compromised woods, in both homes and outdoors, to build into or travel through.

What Attracts a Carpenter Ant to a House?

The most important key factors that attract carpenter ants in homes and yards are moisture and dead wood. In order to prevent a carpenter ant infestation in homes and on property, residents should inspect and repair water leaks from faulty pipes,  leaky roofs or floodings. Wood structures compromised with such moistures must be ventilated to dry. If possible, eliminate or reduce dead/decaying wood, logs or tree stumps from yards. Trim back shrubs or tree branches that touch the house. Indoors, homeowners can prevent the attraction of carpenter ants by cleaning up food spills and putting meals away as soon as possible. Removing excess moisture from the air by proper ventilation also helps deter carpenter ant infestations.

When are Carpenter Ants Most Active?

Carpenter ants tend to come out during the spring season. Like all other insects, the carpenter ant is a cold-blooded animal whose body temperature fluctuates to match the changes in temperature of the surrounding environment. During the winter in Canada, where the season often produces bitterly cold weather, carpenter ants become incapable of maintaining a body temperature high enough to support physical activity. Consequently, the insects hibernate in the nest and remain inactive until the arrival of warmer weather in the spring. 

Even though most carpenter ant colonies become dormant in winter, indoor nesting and sightings  are possible. For indoor carpenter ant colonies to remain active during the winter, the nest must occupy a site in close proximity to a heat source. Wall voids directly in the path of sunlight or heated air from a furnace often provide the warmth needed to stimulate the activity of carpenter ants. When carpenter ants inhabit heated indoor areas during winter, the insects typically wait until the nighttime hours to come out and search for sources of moisture in places like bathtubs, dishwashers, sinks and toilets. However, on particularly sunny days, carpenter ants may emerge from the nest and explore other parts of the home. During the winter months, the presence of carpenter ants actively moving around in the house is a clear indicator of an indoor infestation.

Orkin Canada Can Help Get Rid of Carpenter Ants in Your Home

If you have a carpenter ant infestation in your house, an Orkin Pro can help. We use the most effective and appropriate treatment strategies to get rid of carpenter ants.. In cases of extreme infestations and structural damage, homeowners should consider replacing damaged baseboards, floorboards, struts, studs and joists due to the compromised strength of the woods after carpenter ants have successfully been treated and controlled. Replacing affected wood may also limit access points for future infestations. Contact us for more details on carpenter ant pest control.

Reviewed by Alice Sinia, Ph.D., MSc on August 9, 2024.

With more than 20 years of experience, Alice is technical advisor, also responsible for the management of the Orkin Canada Quality Assurance Laboratory located at our GTA Training Centre. She performs analytical entomology (investigates product adulteration using biochemical and comparative tissue methods), and provides technical support in pest/insect identification to branch offices and clients nationwide. In addition, Alice also prepares scientific reports for Orkin Canada clients, updates Orkin management on any changes or updates to any government regulations pertaining to the pest control industry. Alice also performs quality assurance account compliance audits.