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UK College of Agriculture
Un of Minnesota

A few silverfish are not a serious problem but you can do some things to help keep them from getting out of hand. First make sure you don't have any moisture problems and increasing ventilation to areas that they congregrate like basements, attics and crawl spaces. Store boxes and the like that have paper materials off the floor, especially in ares that are prone to moisture and humidity. Glue boards and sticky traps can catch some. Use fans in bathrooms frequently so as to reduce humidity. You can also reduce silverfish and firebrats by removing sources of food, especially in damp areas. You can reduce potential hiding places by removing old papers, books, boxes and other clutter. Seal cracks and crevices, including those found in baseboards, cupboards, and walls to limit harborages. Make sure that adequate ventilation is provided to avoid moisture accumulation in the attic. Ventilation devices, such as soffit / ridge vents or roof vents can be installed to avoid moisture accumulation. Trees that overhang a roof may also add to the moisture build up and should be pruned back to promote air circulation.

We treat all areas where they can be present including the inside of the home, the crawl space and the attic areas. The attic is a hot spot and unfortunately most attics pose challenges to treatment. Because they are usually heavily insulated, it limits the ability to get materials to the silverfish. Dusts are preferred because of the long residual necessary to kill silverfish protected by the insulation but current construction uses a lot of recessed lighting which both limits the ability to use dust and gives insects a pathway to the inside of the home. Therefore sometimes we have no choice but to use shorter residual materials like fogs, ulvs or aerosols.  Read Straight Talk