Saint-Lambert is a popular residential town on the South Shore, known for its tree-lined streets and characterful homes. It was in a 1970s single-family residence on the waterfront, a stone’s throw from the border with Greenfield Park, that our services were requested. Since the fall, the owner had noticed a gradual invasion of spiders in the finished basement, the downstairs closets and the upper corners of the living room. The multiplicity of webs, combined with the presence of a few large wolf spiders that had migrated from the garden, warranted a complete professional intervention.
Property Inspection and Sources of the Problem
The mandated exterminator in Saint-Lambert began with an in-depth visit of the entire property, interior and exterior. Inside, we examined the unfinished basement adjacent to the finished area, the spaces behind the water heater and furnace, and the voids around the ductwork. Outside, we inspected the foundation edge, the spaces under the treated wood patio, and the piles of logs stored against the wall of the house, which provided an ideal habitat for wolf spiders and cellar spiders.
The diagnosis established that the main entry route was a series of cracks in the foundation parging on the north side of the house, aggravated by the freeze-thaw cycles typical of the Quebec climate. Several small insects, including mosquitoes and woodlice, attracted to the moisture in the subsoil, provided an abundant food source for the resident spiders.
Coordinated interior and exterior treatment
Our spider extermination program for this residency involved several concurrent components. Inside, after vacuuming all the canvases and visible individuals, we applied a wettable powder insecticide in the cracks and nooks of the unfinished basement, as well as a strip spray on the baseboards on the ground floor. The selected products have a safety profile adapted to residential environments with pets, an important point for this owner who owned a cat.
Outside, perimeter treatment was applied to the foundation strip to a height of 30 cm, to basement door and window frames, and around the patio. Firewood was recommended to be moved at a reasonable distance from the house. To reinforce the external barrier, we have also implemented an exterior insect treatment covering the entire perimeter of the building, with particular attention to shaded and humid areas.
Caulking and preventive measures
Sealing the entrance routes is an essential component of a long-term intervention in an old house. Our technicians applied acrylic caulk to the identified foundation cracks, installed a new threshold joint under the basement service door, and filled in the gaps around the plumbing pipe penetrations. This caulking of entry points not only reduces the arrival of spiders, but also that of other pests such as mice as winter approaches.
The homeowner also received personalized recommendations: reduce the humidity in the basement with a dehumidifier, remove plant debris accumulated against the foundation and install screens in good condition on the basement windows. To complete your information, check out our case study spiders in residence. The team of certified exterminators on the South Shore and the South Shore remains available for any follow-up or additional questions.
Assessment of the intervention
Two weeks after the intervention, the follow-up visit confirmed the absence of new webs in the previously infested areas. The owner, relieved, was able to enjoy her finished basement without the fear of encountering spiders. The combination of interior and exterior treatments, caulking and preventive advice is the most effective formula for this type of old property in the climate context of the South Shore. Homes built before the 1980s often have less airtight building envelopes, making them recurring targets for many pests. Maintaining seasonal vigilance and having the foundation inspected every fall are simple habits that prevent many future infestations in Saint-Lambert and nearby cities on the South Shore.