Contrecœur is a city in the Montérégie region established on the south shore of the St. Lawrence River, between Verchères and Sorel-Tracy, where residential neighbourhoods, a port area and farmland rub shoulders. This proximity between built-up areas and wooded areas creates significant migratory pressure of rodents to heated buildings every autumn. It was in a condominium building of about ten units that residents on the ground floor reported traces of mouse activity in the common storage room and in the false ceilings of the corridors. Managing an infestation in a condominium is significantly more complex than in a single-family residence, as mice move freely between units through common wall cavities and shared plumbing passages, and any partial intervention only shifts the problem. Our team of exterminators in Contrecoeur took charge of the entire file with the rigor and discretion that this type of mandate requires.
Building Assessment and Infestation Pathway Mapping
The rodent infestation inspection covered the entire building over two days: technical rooms, crawl space, wiring gallery, electrical room, meter room and all common areas. Droppings, footprints in the fine dust of false ceilings and gnawing marks on electrical wires confirmed the active presence of house mice on several levels of the building. Accurate movement mapping revealed that rodents circulated primarily through vertical heating pipe passages and mechanical ventilation ducts shared between units. The inspection of the private units, carried out with the written agreement of each owner, detected signs of activity in five of the ten apartments, concentrated mainly in the kitchens and cupboards adjacent to the exterior walls. The main entrance to the building was identified at the level of the foundation on the north side, where a subsidence of the ground had created a gap between the plaster and the slab. A second secondary access passed under the door of the garbage room in the basement, whose bottom seal was completely damaged.
Coordinated treatment program in all units
Our mouse extermination program in this Contrecœur condominium was based on a multi-zone protocol, deployed simultaneously in all accessible units and in the common areas to prevent mice from migrating from one part of the building to another in response to treatment. Secure baiting stations, in compliance with Quebec pesticide regulations, have been installed in technical spaces, basements, corridors and accessible false ceilings, always out of reach of residents and their animals. Multi-catch traps have been set up in the crawl space and mechanical rooms. Each station has been numbered and geolocated on a map of the building given to the manager to facilitate checks. Three follow-up visits spaced ten days apart confirmed the gradual elimination of rodents throughout the structure.
Decontamination of soiled common areas and closure of access
In the common areas where the mice had circulated for a long time, in particular in the false ceilings of the basement corridor and in the boiler room, a complete decontamination after rodents was carried out. Dried droppings and nests located in the attic insulation were removed in accordance with the respiratory protection protocols recommended for this type of work. Disinfection with a virucidal agent approved for professional use was then applied to all contaminated surfaces to eliminate any bacteriological risk. The caulking of the openings identified in the common areas included sealing the foundation breach with hydraulic mortar and an anchored galvanized sheet metal plate, replacing the bottom of the door seal in the garbage bin room with a rodent-resistant aluminum model, and sealing all duct passages in the common walls with steel wool and fire-resistant foam. The union received a complete preventive action plan to integrate into its annual maintenance schedule, including an inspection of the exterior perimeter at each change of season and a verification of the condition of the door seals in the common areas. Check out our mouse extermination project in another residential building to discover comparable situations that we have successfully solved on the South Shore.
Do you hear scratching at night or find feces in your cupboards? Nova Extermination intervenes quickly in Contrecœur and throughout the South Shore to eliminate mice in a sustainable way.