Case Study Mice Use Holes in Deck to Reach Kitchen in Old Toronto

Case Study: Mice Use Holes in Deck to Reach Kitchen in Old Toronto

This case study details a mouse removal and pest-proofing job in Old Toronto. Mice entered this 2-unit home in early winter via the holes in the foundation, then dirtied the kitchen with feces. A thorough inspection of the property, along with an extermination program and exclusion of the foundation has left this property mouse-free ever since. Call The Exterminators today for guaranteed mouse control in Toronto and beyond.


The homeowner in this case gave The Exterminators a call when they first started noticing the signs of a rodent problem in their home. They found droppings in their kitchen and could hear scratching in the walls. Rodent intrusions like this one are common in the winter, when this took place. Rodents, like us, look for a warm place to live out the winter. A technician quickly came to the scene to investigate.

The first thing our technicians do when treating a pest problem is to carry out an inspection. This helps to identify the causes of the infestation, so we can address them. Getting rid of the pests while addressing the causes prevents an infestation from ever happening again.

Here, the technician found gaps in the home’s foundation. Little holes in the sides of the front deck were visibly wide enough to let in mice or rats. It only takes about one quarter of an inch to let mice inside. They can crawl in through gaps in the deck, then gaps in the foundation and into the walls of the home. To fix this, the technician recommended having them sealed with caulking.

Hole in Stone Deck Mouse Entry Point
Holes in the stone, like this one, let in mice and rats. Once under the deck, they may dig through the foundation and into the home.

Indoors, the technician found the droppings in the kitchen that the homeowner had found before. This indicated the concentrated area of mouse activity, which would be where the treatment would take place. Mice often nest near kitchens because this is where the food is. They can find crumbs and little morsels of food in this area of the house.

At the end of the inspection, the technician informed the homeowner of what was going on and explained the steps of the elimination process. Bait stations would need to be placed in the kitchen to get rid of the mice directly, and the holes in the deck would need to be closed. The homeowner agreed with the technician’s proposal, so the technician got right to work.

Treatment and Exclusion

First, the technician placed a few bait stations around the kitchen and main floor of the home. Bait stations are little containers of rodenticide, with holes in their sides to let mice inside. Mice are attracted to the bait’s smell and come to feed when they are hungry. After a few ingestions, the mice feel sick, and they perish in their nests. Only a licensed pest control technician has access to these stations, and they are secured by lock and key.

Once the bait stations were installed, the technician went back outside to fix the holes in the foundation. This would keep the mice indoors and prevent any more from entering inside. Four holes were sealed with a combination of steel mesh and sealant. The mesh is thick enough so that it cannot be chewed by rodents, and the sealant would block everything out, even insects.

Exclusion of Mouse Entry Point
The combination of mesh and sealant ensures that no animal will dig its way through.
Exclusion of Hole in Wall
A hole this large could fit a raccoon or a skunk, so it was sealed with mesh.


By February, the mice in this Old Toronto home were gone. The homeowner was no longer hearing any noises, and there were no feces on the ground. A technician came to check up on the property and monitor the bait stations, to find that feeding had slowed and stopped.

With every rodent problem, it is important that the point of entry be located and sealed off. Pests always come from outside, so there is always a way in. Treating for the mice and excluding them from the property rid this property of mice, and they will likely be pest-free for many years to come.

If you’ve been struggling with a rodent problem, get the help of a professional. The technicians at The Exterminators are trained, licensed, and experienced professionals. We deal with mice all the time. We can find the animals’ entry point eliminate them, and keep them out for good. Our exclusion services come with a 2-year warranty. Call us for mouse removal in the GTA and beyond.