Case Study Carpenter Ants Crawl Through Skylight in East York

Case Study: Carpenter Ants Crawl Through Skylight in East York

In this case study , we will look at an interior carpenter ant extermination in East York. Carpenter ants were crawling through cracks in the skylight’s window frame and damaging the home, but a complete extermination got rid of them effectively. If you suspect some carpenter ant activity on your property, reach out to The Exterminators.

East York, Toronto

The former borough of East York, located in the east end, was amalgamated into the City of Toronto in 1998. It is bordered by Scarborough to the east, North York to the north, Bayview Avenue to the west, and Danforth Avenue, roughly, to the south.

The Canada Day parade in East York
The Canada Day parade in East York.

Rapid gentrification has seen residential neighbourhoods go from single dwelling bungalows to two-storey homes. Many shops and restaurants in the area are now considered upscale. Despite its gentrification however, pests continue to invade the homes and businesses in East York. Older buildings and matured parks create an environment that is perfect for carpenter ants.


This East York customer called us concerned that carpenter ants had infested their home. Ants were seen coming in from a skylight and roaming around the house.

Skylight Ant Entry Point
Inside access to the skylight proved to be challenging.

We immediately sent one of our licensed exterminators to the location to perform an inspection and treat the infected areas accordingly.

Because the skylight was located in a high and confined space inside the home, our technician decided to climb on the roof to better understand the ant activity. Carpenter ants were seen crawling through the tight crevices of the skylight frame and entering the home’s ceiling.

Window Frame Cracks Ant Entry Point
Carpenter ants moved through small gaps around the skylight frame.

These roaming ants are likely worker ants from a nearby colony that will often stray from their nest in search of food for the queen and young ants. They could also be ants that are ready to participate in what is known as a nuptial flight. Once days begin to warm up in the Spring, winged ants in satellite colonies will take flight and mate. The males will die after this ritual, and the female queens will look for a place to lay their eggs and start a new colony.


Due to the challenge of accessing the interior of the skylight, our technician treated the exterior fixture with an insecticide dust. This dust is finely formulated and is able to penetrate small cracks and gaps in exposed surfaces. This highly effective insecticide quickly kills ants on contact.

Insecticide for Carpenter Ants Window Frame
An insecticide dust was applied around the exterior of the skylight.

As an added measure, we also sprayed an additional insecticide inside the home to exterminate any ants left inside. This spray is designed to adhere to surfaces such as baseboards, window and door frames, and other areas of high activity and will be active for up to 90 days due to its residual properties. Ants that come into contact with it will die after the insecticide’s micro beads penetrate their bodies.


All of our extermination work is backed with a six-month warranty. In the case of this homeowner, ants had returned within our warranty period and we returned to perform another treatment.


This customer was quick to observe the carpenter ants entering their property via a skylight on the roof and took immediate action. We were able to identify the entry point and treat all affected areas before the problem became a nuisance.

Although uncommon, carpenter ants may return to the same location after treatment. Some of the reasons for such a re-infestation to occur could be abundant food sources, or high moisture areas. After treating a carpenter ant infestation, we advise our customers to keep surface areas free of food, especially around the floors. Any water leaks, if present, should be fixed as well in order to minimized moisture in the home.