In Saint-Denis-sur-Richelieu, a historic village in the Montérégie region on the east bank of the Richelieu River, the presence of spiders in an apartment building can quickly become a source of concern for residents. Our team of exterminators in Saint-Denis-sur-Richelieu was called to intervene in a twelve-unit building located in the heart of the village core, where several tenants reported accumulations of webs and the regular presence of spiders in the common corridors, storage rooms and even inside the apartments. The situation affected the ground floor and basement dwellings in particular, where moisture and cracks in the foundation favour the installation of these arachnids.
Thorough inspection and species identification
As soon as we arrived, Nova Extermination’s certified technicians carried out a thorough inspection of the entire building: foundations, crawl spaces, mechanical rooms, corridors, door and window frames. We identified mainly common house spiders, spiders and a few wolf spiders that had entered from the outside through faulty seals around windows and pipe passages. The presence of insect prey, including springtails and mosquitoes linked to the ambient humidity, explained the attraction of the building for these predators.
The inspection also identified areas of stagnant moisture in the basement, cluttered storage spaces suitable for nesting, and several potential entry points at the top plate and floor joists. A detailed report was submitted to the building manager before any intervention.
Targeted treatment and methods applied
Our protocol for an apartment building uses a multi-step approach. Firstly, we carried out a complete vacuum of all visible canvases in the common areas, garages and basement, thus immediately reducing the population load. Then, we applied an insecticide spray treatment to the baseboards, foundation joints, frames and exterior perimeters of the building. The products used are approved for residential use and applied in accordance with the safety instructions for occupants.
In the enclosed common areas such as the waste room and the mechanical room, we set strategically placed sticky traps to capture individuals on the move and monitor the evolution of the population over several weeks. An exterior treatment at the edge of the foundation was also carried out to create a perimeter barrier. To learn more about this approach, visit our page on outdoor insect treatment.
Sealing of points of entry and recommendations
The real challenge in an apartment building is to prevent new introductions. Our technicians identified and sealed about twenty entry points: gaps around plumbing pipes, degraded window seals, cracks in the foundation parging and openings under service doors. The use of professional-grade point of entry caulking is an essential step to ensure the durability of the treatment in this type of building.
We also recommended that the manager reduce outdoor lighting in the evenings, which attracts flying insects that prey on spiders, and keep storage spaces tidy and ventilated. A follow-up visit was scheduled four weeks after the initial treatment to check the effectiveness of the measures and adjust if necessary. Our customers interested in consulting other similar projects can read our case study spiders in buildings for a complementary example.
Long-term results and follow-up
Thanks to the comprehensive intervention of our team, the residents of the building quickly noticed a significant decrease in the presence of spiders in their living spaces. The manager reported during the follow-up that the hallways and basement were virtually free of canvas. For long-lasting results, our team specializing in spider extermination recommends an annual preventive treatment in early spring and autumn, when spiders seek to enter heated buildings. Proactive management is the best guarantee of peace of mind for owners and tenants in this rural and agricultural environment.