In the middle of summer on the South Shore, a homeowner from Saint-Basile-le-Grand contacted us after discovering a large wasp nest hidden under the vinyl siding of his single-family home. The colony had settled in the cavity between the exterior cladding and the insulation, a few meters from the terrace where the family spent their evenings. The nearby Saint-Hubert sector had experienced strong wasp activity that same season, a sign that the weather conditions favoured a marked proliferation throughout the region. As soon as the call was received, our team planned a quick intervention to secure the residential perimeter.
Nest inspection and identification
Upon arrival on the premises, our technician made a complete tour of the property in order to identify all the points of activity. Observation of the flight behaviour of the workers made it possible to precisely identify the main entrance to the nest, a crack of about two centimetres between two vinyl planks located under the eaves on the south side. By discreetly probing the wall, the technician was able to estimate the size of the colony from the characteristic chewing noise that wasps produce when they enlarge their papier-mâché nest. It was a common wasp, a particularly aggressive species when it feels threatened. The complete survey of the secondary entrance areas also revealed two additional small openings under the soffit at the northwest corner of the building.
Professional treatment: insecticide injection and sealing
The technician opted for a direct injection of residual insecticidal powder into the wall cavity through the existing openings. This method allows the entire nest to be reached without demolishing the coating, while ensuring that the product is deposited on the workers who are constantly transiting between the nest and the outside. A complementary treatment in the immediate periphery, in the form of a spraying of a registered liquid insecticide, was applied to the surfaces around the openings to eliminate the return workers that had not been affected during the first application. In accordance with best practices in wasp extermination, the intervention was carried out in the evening, when almost all the workers are in the nest, thus maximizing the effectiveness of the treatment. To learn more about our interventions in this sector, visit the page of our exterminator in Saint-Basile-le-Grand.
Sealing and long-term prevention
Once the colony was neutralized, our team returned forty-eight hours later to confirm the absence of residual activity. The inactive nest was removed from the wall cavity to prevent it from serving as a host for another colony the following year, as wasps are attracted to pheromones left in old nests. All openings identified during the inspection were then sealed with caulking of the entry points based on expanding foam and weather-resistant exterior sealant. Specific recommendations were given to the homeowner: reduce sources of sugary food outside, inspect soffits and roof corners every spring, and regularly check the integrity of the siding. Our technicians also reviewed the areas of dense vegetation at the edge of the property, as some bushy shrubs may harbour underground nests. To see another similar intervention, you can read our work on a wasp nest that has recently been treated. Nova Extermination offers a rigorous follow-up after each intervention to guarantee the peace of mind of our customers on the South Shore and throughout the greater Montreal area. At the end of the intervention and the follow-up, the residence was completely free of all wasp activity. The family was able to safely resume the use of their terrace the following weekend. This type of mandate illustrates the importance of acting quickly when a colony is established within a building wall: the longer you wait, the larger the colony and the more complex it becomes to remove the nest. A mature nest can contain several thousand individuals and occupy a considerable volume, making the decontamination work much more laborious at the end of the season.