The syndicate of a twelve-unit condominium located in the heart of Old Saint-Lambert, on the South Shore, mandated our services after several co-owners reported the presence of pharaoh ants in their respective units. Managing an infestation in a condo is particularly complex, as colonies can move freely between units via shared walls and ceilings, making any partial intervention completely ineffective in the long run. An isolated action in a single unit can even aggravate the situation by dispersing colonies to neighbors through the phenomenon of splitting, a survival mechanism specific to this species. This required a coordinated simultaneous response across the entire building, which required full buy-in from all residents and clear communication about the process. Nova Extermination’s team on the South Shore was able to mobilize the co-owners around a common and coherent action plan, guaranteeing maximum effectiveness of the treatment throughout the Saint-Lambert co-ownership.
Coordination with the union and collective inspection
A first information meeting was organized with the members of the union to explain the biology of pharaoh ants, the risks associated with a fragmented intervention, and the proposed treatment protocol. This communication step is essential to gain access to all units and ensure that no one is using repellents that would compromise the effectiveness of collective baiting. After the agreement of all the residents, our technician carried out a complete inspection unit by unit, as well as the common areas including the hallway, the laundry room and the technical room. Saint-Lambert is adjacent to LeMoyne, and this type of old condominium often has large wall cavities that facilitate the spread of colonies between floors and between adjoining units. Our exterminator in Saint-Lambert mapped the areas of activity in eight of the twelve units, as well as the common laundry room and basement ventilation ducts, providing a solid and documented foundation for the overall treatment plan.
Coordinated Building-Wide Treatment
The treatment with baits specific to pharaoh ants was carried out in a single day in all the units and common areas. This simultaneity is crucial to prevent colonies from migrating from a treated area to an area that was not treated during the intervention. Each unit has received a personalized treatment according to the areas of activity observed during the inspection, with a higher concentration of bait in the kitchens and bathrooms, where the humidity and heat conditions are most favorable. The common areas have been treated as a priority in the transit areas of the identified tracks, in particular the laundry room and the technical basement. A list of instructions was given to each co-owner, insisting on the importance of not cleaning the baiting areas with strong disinfectants and avoiding any commercial insecticides for the duration of the treatment. Discreet monitoring traps have been installed in the common corridors to monitor the evolution of activity between planned control visits.
Assessment and recommendations for the co-ownership
Follow-up visits confirmed a gradual and sustained reduction in activity starting in the third week, which is fully in line with expectations for this type of infestation in a multi-unit building. During the final visit, at the sixth week, all the residents no longer reported the presence of ants in their respective units or in the common areas. To prevent a recurrence, we have submitted a report of recommendations to the union on preventive maintenance, including sealing plumbing passages between units, repairing deteriorated tile joints in bathrooms, and implementing a rapid reporting protocol in the event of a reappearance. An annual pest prevention plan for the condominium as a whole was proposed, including seasonal inspections of common areas. A decontamination of the common surfaces and pipes completed the intervention to eliminate residual runway pheromones. Read our case study on a similar co-ownership successfully treated on the South Shore.