Case Study: Rat Infestation in Home in Rosedale

Today we will look at a case in which rats breached into a home and roamed along the perimeter of the property in Rosedale, in the heart of Toronto. The Exterminators Inc. were quick to identify the key problem areas and exterminate the rats from the home. Rosedale, located in the heart of downtown Toronto, is known for its beautiful parks, quiet streets, and the ravines that border it. With a history dating back to the early 1800’s, Rosedale’s character is emphasized by its older homes, some dating back over 100 years. This neighbourhood is also flanked by two small waterways- Mud Creek and Yellow Creek – both of which empty into the nearby Don River. ROSEDALE01 Whitney Park in Rosedale The combination of older homes and nearby waterways likely contributes to a higher abundance of rodents in the area. Rats, in particular, are known to strive in neighbourhoods near water, such as Rosedale, Riverdale, Leslieville, and the Beach.

Inspection and Assessment

The property owner contacted us on the suspicion that a rat or rats may be in her home. Our technician visited the property for an initial assessment and determined that rat activity was taking place in a crawl area under the kitchen. We suspected that other areas of the home may have been infested as well. ROSEDALE01-INSPECTION2 Potential entry points were identified under the deck. As part of our full inspection, we did a full assessment of the exterior of the home as well. Our technicians always search for evidence around and near the property to determine any points of entry, nesting sites, and any other signs pointing to rodent activity. This is an important step we take very seriously to ensure the source of the infestation is identified and dealt with, not just removal of the pests. During this inspection, our technician found potential points of entry along an extension wall under the deck. Rats will often find cracks on walls that permit entry into the structure, or will even burrow a hole to bypass the foundation. We also found that the homeowner had setup multiple birdfeeders in the backyard. The feed was stored in the garage, but with a door that did not quite seal the entrance, it appeared that the rodents had been feeding from the bags.

Initial Steps

Toronto Public Health recommends that birdfeeders be removed to help control rodent infestations. Our technician advised the homeowner that it would be best to remove the feeders and all bird seed to help control the rats. The homeowner agreed. Bait-stations were then installed on the exterior of the property and snap traps placed inside the home. This initial setup is sometimes enough to eliminate the pests, but in this case the technician noted that an exclusion was likely going to be necessary along the rear of the house, where the deck meets the wall. ROSEDALE01-FOLLOWUP Bait stations were installed on the exterior of the property. Bait-stations are tamper-proof containers that are stocked with rodenticide. Once eaten, the rats will perish. These bait-stations can only be accessed by a special key and prevents children and pets from accessing the bait. They are loaded with a commercial grade rodenticide that only licensed exterminators can use.

Rat Exclusion Installation

After visiting the home to check on the bait-stations, it was concluded that the problem persisted within the home. Our technician proceeded to install 30ft of galvanized steel mesh, a durable material made to withstand gnawing. The mesh was installed along the rear wall under the deck to prevent the rats from burrowing into the structure. Rosedale-Exclusion2 A metal mesh is installed along the perimeter of the property to prevent entry. A one-way-door was also installed at the point of entry. This feature allows for any rodents that are still present within the home to exit and not be able to re-enter. The door makes for a speedier resolution of the interior rat problem. Rats will use the door to exist the structure and the exclusion will keep them out. All bait-stations were refilled as well to maintain control of the exterior of the home.


A month after the exclusion was complete, we returned to close and seal the one-way-door. Bait-stations were re-filled and the homeowner informed to allow 3-4 weeks to see results on the exterior of the property. ROSEDALE01-OWDSealed One-way-door was removed and sealed at suspected point of entry. Our customer service team followed up with the homeowner a month after the last visit and confirmed that there was no longer any rodent activity in or around the property. The customer was fully satisfied with the service.


From the initial visit to our follow ups, our team of professionals was able to identify the sources of the infestation by doing a thorough inspection of the property, both inside and outside. The outside inspection was crucial as it led to prevention of future infestations. As is often the case, eliminating the rodents from inside the property does not guarantee they will not return. By educating the homeowner about the bird feeders and installing a mesh around the perimeter of the extension, we minimized the return of rats to this property in Rosedale. All our rodent exclusion work is backed by a six month warranty. Should the rats infiltrate the home through one of our installations, we will return to repair or replace it.