It's Pest Season. Exterior Painting Can Actually Help

When people think of exterior painting, they see it as a cosmetic, surface-level upgrade; something to improve the curb appeal of the home and make it look new.

But below the surface? A properly maintained exterior via painting can serve a much more important purpose: protecting the home from moisture. Why does this matter? Because moisture-damaged wood is the number one condition that attracts carpenter ants, a well-known pest that can damage the wood structures that support homes.

According to Health Canada, carpenter ants are among the most common wood-damaging insects found in Canada. While they don’t eat wood like termites, they dig tunnels (called galleries) much longer than those created by termites. The wood is not eaten but thrown from the nest as sawdust-like shavings.

Carpenter Ants Are Often a Sign of Moisture Problems

One of the most important facts to consider is that carpenter ants are typically attracted to moisture damaged wood.

Health Canada notes that carpenter ants prefer moist, decaying wood and often indicate an underlying moisture issue within a structure. Similarly, the University of Maryland Extension reports that damp or rotting wood is especially attractive because the softened wood fibers make tunneling easier.

This is exactly where exterior painting can be a solution!

Sealing Cracks and Gaps Reduces Entry Points

However, before applying paint on the exterior, companies like Letts Paint look for cracks where wood trim pieces meet, such as door frames, window frames, or loose wood siding. Moreover, Health Canada identifies openings around foundations, utility penetrations, and other exterior gaps as common entry points for carpenter ants. By sealing these crevices before painting, homeowners can reduce the number of ways for carpenter ants to enter. Paintable white caulking and sturdy exterior paint are exactly the tools that can help achieve

this.

Repairing and Painting Over Damaged Wood Removes Attractive Nesting Areas

Damaged wood is another concern and attractive to carpenter ants. A quality exterior paint project should never simply cover deteriorated wood and needs to be replaced before painting, or the pest risk increases substantially.

The University of Minnesota Extension recommends replacing moisture damaged wood as part of carpenter ant prevention. Likewise, Utah State University Extension identifies removing and replacing water-damaged or decaying wood as a key integrated pest management strategy.

When moisture damaged wood is repaired and protected with primer and paint, homeowners eliminate one of the most attractive nesting environments for carpenter ants.

Exterior Primers Help Protect Wood from Moisture

A well-known fact about the purpose of exterior primers is to improve adhesion and create a protective layer between the substrate and the finish coat. A less well-known fact is the high-quality primers help reduce moisture penetration into wood surfaces, which is critical because carpenter ants preferentially nest in moisture-compromised materials.

No paint can fully prevent pests like carpenter ants, but a properly primed and painted exterior helps maintain dry, sound wood conditions that are far less attractive.

As the U.S. National Park Service explains, carpenter ants commonly establish nests in building materials weakened by moisture. Protecting wood from water intrusion therefore reduces the conditions that support nesting activity.

Regular Repainting Is Preventive Maintenance

Paint doesn’t last forever; it tends to wear away over time due to sun and exposure to the elements.

Therefore, routine inspections and timely repainting are key to keep moisture away from exterior wood surfaces. By addressing peeling paint, failed caulking, and exposed wood early, homeowners can reduce the likelihood of moisture damage and possibly carpenter ants.

The Bottom Line

A fresh paint job will not eliminate carpenter ants on its own. However, proper surface preparation, crack sealing, wood repair, priming, and painting all contribute to a drier, better-protected exterior.

Because carpenter ants are strongly associated with moisture damaged wood, maintaining a sound paint system can help remove the conditions they need to establish nests around your home. In that sense, exterior painting is not just a cosmetic improvement; it's an important part of long-term pest prevention and home maintenance.