In Saint-Bruno-de-Montarville, on the South Shore of Montreal, a family owner of a single-family residence built in the 1990s called on our team after noticing rodent tracks in the crawl space and attic. The building, located not far from the Grand Coteau sector near Marieville, had numerous cracks in the foundation and deteriorated expansion joints that allowed mice and voles to infiltrate freely. Before undertaking any treatment, it was essential to identify and seal each entry point to ensure a sustainable solution. Our caulking and exclusion service solved the problem at the source rather than just treating the visible symptoms.
Initial inspection and breach mapping
The mandated technician carried out a complete inspection of the building envelope, starting with the exterior perimeter of the foundation. Using a headlamp and an inspection mirror, he identified several types of vulnerabilities: stepped cracks in the foundation concrete, gaps around plumbing and electrical ducts running through the wall, peeled door and window seals, and a partially degraded roof soffit that provided direct access to the attic. Each defect was photographed and recorded in a detailed inspection report provided to the owner. This accurate mapping is the first essential step in planning closure work effectively.
The inspection also looked at the interior: the crawl space had holes in the vapour barrier and unfilled gaps around the heating pipes. Biological clues (droppings, traces of rubbing, nests of displaced insulating wool) confirmed active rodent activity. Our team was able to establish the priority areas to be addressed first, thus optimizing the work flow.
Caulking and sealing work
The work began with the critical entry points at the foundation level. The concrete cracks were mechanically enlarged to ensure optimal adhesion and then filled with fast-setting hydraulic mortar. The spaces around the plumbing ducts were closed with compressed steel wool, then covered with an exterior-grade polyurethane sealant that is resistant to UV and extreme temperatures in Quebec. This combination of materials is impassable to rodents, which are unable to gnaw on steel wool.
At the roof level, the damaged soffits were replaced with fine-mesh perforated aluminum panels, and the edge joints were checked and repaired with acrylic caulk. The spaces around the ventilation ducts in the bathroom and kitchen were lined with mechanically attached galvanized steel screens to block access to birds and raccoons without obstructing the necessary ventilation. Inside the crawl space, the holes around the pipes were closed with reinforced expanding foam and wire mesh.
The work ended with the systematic verification of each intervention, confirming the tightness of all the points treated. For homeowners who want to go further in prevention, we recommend a smoke test to detect breaches invisible to the naked eye in the ducts and structure.
Long-term follow-up and prevention
A follow-up visit was scheduled four weeks after the work to check for new signs of activity and to ensure that all caulking materials remained intact. The owner received practical advice: keep trimmed vegetation away from the building, avoid storing firewood against the foundation, and visually inspect the perimeter every fall before the cold weather. Our extermination team in Saint-Bruno-de-Montarville is available for any annual follow-up or in case of reappearance of signs of infestation. To discover other similar work done in the region, see our previous caulking or this other case study in exclusion. By choosing Nova Extermination, homeowners in Saint-Bruno-de-Montarville and the surrounding area benefit from a rigorous approach, without unnecessary chemicals, focused on the permanent closure of access roads.