A family from Sherbrooke, on the South Shore, contacted Nova Extermination after discovering silverfish in several rooms of their single-family home. These discreet insects, recognizable by their tapered silver bodies and sinuous movements, had settled in the humid areas of the house for several months before being detected. The property, built in the 1980s and surrounded by dense vegetation, presented ideal conditions for the establishment of this species. The Sherbrooke area, located not far from Saint-Constant, is conducive to this type of infestation because of the presence of semi-buried basements and old window frames that are less well insulated.
Inspection and assessment of the infestation
As soon as our certified technician arrived, a rigorous inspection was conducted in all at-risk areas of the home. Silverfish are particularly fond of dark, cool and humid places: basements, bathrooms, kitchens, poorly ventilated closets and spaces under sinks. The examination revealed characteristic marks, including irregular bites on cellulosic materials such as peeled wallpaper, cardboard stored in the basement and pages of books left in a storage room. Translucent moults, small and light, were also found behind the baseboards of the laundry room.
The relative humidity measured in the subsoil exceeded the critical threshold for this pest. Cracks in the perimeter of the foundation windows and a poorly sealed door seal were the main suspected routes of entry. This assessment phase is essential to guide effective treatment: understanding why silverfish thrive in a building is key to a sustainable response. Our silverfish extermination service always starts with this thorough diagnostic step.
Targeted therapy and methods used
For this Sherbrooke residence, the protocol used combined several complementary methods to reach all stages of the insect’s development. First, an application of residual insecticidal powder was carried out in cracks, wall cavities, behind baseboards and under household appliances. This powder works by disrupting the cuticle of insects and remains effective for several weeks in uncrowded areas.
In addition, a liquid insecticide with a residual effect was applied to the periphery of the affected rooms, particularly targeting the transition areas between wood and concrete. Sticky baits were placed in strategic locations to confirm residual activity between passages. The technician also advised the family on the immediate measures to take: remove wet boxes from the basement, actively dehumidify this space and avoid storing paper on the floor. This combined approach maximizes treatment efficiency while reducing the overall chemical pressure in the home.
Caulking and sustainable prevention measures
Once the initial treatment was completed, our team proceeded with caulking of the entry points identified during the inspection. The cracks around the foundation windows were sealed with an elastomeric sealant adapted to the frequent thermal movements in Quebec. The spaces around the pipes passing through the concrete slab were also sealed to block the migration routes between the outside and the inhabited space.
Moisture management is the most decisive preventive factor against silverfish. It has been recommended to install a basement dehumidifier and maintain a humidity level below 50% in all rooms of the house. Similar prevention work has been carried out as part of a project on spiders, another pest found in the same environmental conditions. For personalized advice on long-term prevention, visit our Pest Prevention Plan page.
Monitoring and results obtained
Follow-up was performed three weeks after the first treatment. The family had not observed any live insects since the second week after the procedure. The sticky traps were no longer showing activity, and the moving boxes removed from the basement had given way to airtight plastic storage bins, which were much less attractive to this pest. The humidity level in the basement had been reduced to an acceptable level with the installation of the recommended dehumidifier.
At Nova Extermination, we believe that successful treatment is as much about the technical act as it is about supporting the customer. The Sherbrooke family leaves with a sanitized house, practical knowledge of the behaviour of this pest and a vigilance plan to avoid recurrences. Silverfish can come back if the favorable conditions are not corrected: this is why we always insist on environmental measures in addition to chemical treatment. To see another case treated in the region, see our realization on house ants, a pest often present in the same types of properties.