Saint-Lambert, a residential city on the South Shore known for its tree-lined streets and characterful buildings, is also home to several professional office buildings, particularly in its downtown area and along Saint-Laurent Boulevard. These tertiary workspaces, frequented by professionals such as accounting firms, notarial offices or clinics, are generally less affected by pests than food shops, but are not immune to anthills when the external conditions become favourable. A shared office building in downtown Saint-Lambert, not far from Greenfield Park, contacted us after several tenants reported ants on their desks and around the communal coffee machine.
Assessment and source identification
The after-hours inspection traced the source of the infestation. The ants did not come from an indoor nest but entered the building from the outside through an expansion joint on the façade, at ground floor level. An active nest had been established in the cracks in the brick masonry on the façade, exploiting the spaces between the bricks unsealed by the years of freeze-thaw cycles typical of the South Shore climate.
The species identified was the pavemente ant, which had found in the office building an abundant food source: crumbs around the coffee machine, snack wrappers left open, and sugary residues in the garbage cans not emptied at the end of the day. These elements had made the interior attractive enough for the workers to develop a stable recruitment trail from the outside nest to the office dining area, regularly followed by dozens of individuals at a time.
Methods of intervention
Treatment has been scheduled to minimize disruption to tenants. The exterior intervention was carried out during the day, while the interior treatment took place in the evening after the closure of the coworking space, allowing for complete ventilation of the premises before the return of the workers the next day.
For the outer nest in the masonry, our technicians applied an expanding foam insecticide injected directly into the open brick joints. This type of foam formulation penetrates deep into irregular cracks and is particularly suitable for brick masonry with cavities that are difficult to reach with conventional liquid injection. The foam cures in minutes, also sealing the entrances after processing.
Inside, bait gels were placed along the identified recruitment track, from the expansion joint on the façade to the coffee machine area. These micro-dot baits are invisible to users of the office but are detected and carried by the workers to the queen. The next morning, the building manager noticed an immediate reduction in the number of ants visible on the surfaces.
The caulking component was also important: our technicians redid the expansion joint on the façade with an elastomeric sealant resistant to temperature variations, and filled the most damaged brick joints with a suitable grouting mortar. To learn more about this step, visit our page dedicated to caulking entry points.
User training and follow-up
The particularity of a coworking space lies in the fact that users change regularly and do not necessarily have the same maintenance habits. We have prepared a short information document posted near the food court, reminding people of good practices to reduce the attractiveness of the premises for insects. This document included basic instructions: store food in closed containers, empty bins daily, and clean up any spills of sugary drinks immediately.
A follow-up visit was carried out four weeks after treatment. The bait gel had worked well: no ant tracks were visible inside. The outer nest showed very low residual activity, and a second application of insecticidal foam to an adjacent joint was made as a precautionary measure.
For a complete description of our treatment techniques, our page on anthill destruction offers an overview of the methods adapted to each situation. Also consult this project in a professional building and this file on ant management in tertiary buildings for other concrete examples. Our team of exterminators in Saint-Lambert is available for any type of property, residential or commercial. Nova Extermination offers you recognized expertise throughout the South Shore and South Shore of Quebec.