Table of Contents
Job Overview
Location: Toronto, Ontario
Structure: Three-storey Victorian century home with front deck
Problem: Rat activity suspected in basement wall cavities and under front deck
Service: Rat exterior treatment and structural exclusion
Visits: Two
Summary
We responded to reports of scratching sounds coming from basement walls in a multi-storey Victorian home. While no interior nesting was confirmed, exterior conditions and structural gaps were consistent with rat activity. Our team completed a two-visit exterior-focused solution involving inspection, trenching, vent protection, sealing, and one-way door installation, followed by confirmation and permanent closure.
Background / Property Context
The property is a century-era brick home with a raised front deck and aging exterior features. The deck structure and foundation perimeter provided sheltered areas beneath the porch, along with multiple penetrations and gaps common in older construction.
Customer Concern
The homeowner reported persistent scratching noises within basement walls and suspected rat activity both inside and outside the structure. No visible interior droppings or damage had been observed at the time of inspection.
Inspection & Findings
Our technician identified several exterior conditions conducive to rat access. Under the front deck, exposed soil and deteriorated wood framing created shelter and concealment. A plumbing or electrical wall penetration showed a large opening, and cracks in brick and along window and door frames were visible. Photos show disturbed soil along the foundation line and open voids beneath the porch area, consistent with rodent travel paths.
Cause Analysis
Rats commonly exploit older homes with aging masonry, gaps around utility penetrations, and sheltered areas such as decks. In this case, warmth and protection under the porch and within wall cavities likely attracted activity, even without interior food sources. Exterior food availability from garbage containers can support rats without them needing to enter living spaces.
Treatment / Removal
As part of the exterior rat control strategy, large weighted tamper-resistant bait stations were placed in areas of high exterior activity. All pest control work was carried out by a licensed exterminator in accordance with Ontario Ministry of the Environment guidelines.
Given the customer’s decision to proceed with exclusion, interior snap traps were not required. Two rat one-way doors were installed at identified primary entry points to allow existing rats to exit the structure without re-entry.
Exclusion & Repairs
Exclusion work completed during the first visit included:
- Approximately thirty-six feet of trenching along the accessible porch perimeter. A one-foot-deep by six-inch-wide trench was excavated, and fine galvanized steel mesh was secured to the porch structure and buried to prevent burrowing.
- Installation of galvanized steel one-way rat doors at main access points.
- Installation of three galvanized steel vent covers over open and accessible wall vents.
- Sealing of approximately two feet of exposed foundation gaps to block rodent access.
- Sealing of roughly twelve feet of cracks around windows and doors using caulking and, where required, galvanized steel mesh.
Photos show mesh screening secured along the foundation, protected wall vents, and restored grading after trenching.
Outcome & Confirmation
At the follow-up visit, the homeowner reported no further scratching sounds in the basement or activity under the porch. Technician Richard returned to remove both one-way doors and permanently seal the openings. A final inspection confirmed all exclusion materials remained intact, and no new activity was observed or reported.
Technician Notes
Richard noted that exterior-focused exclusion was appropriate given the lack of confirmed interior nesting. The combination of trenching, vent protection, and sealing addressed both current access points and future burrowing risks. Conditions at the second visit confirmed successful resolution.
This work was completed by our Toronto pest control team. For pest control inquiries in Toronto, contact 647-496-2211.