What are silverfish?

  • Size: Small, elongated, triangular insects, usually between one-half inch and one inch in length.
  • Color: Typically a shiny gray or silver.
  • Behavior: Silverfish feed on fungal molds and organic matter. They can damage natural fabrics, paper and book bindings. Treatment of cracks and voids as well as attic and crawl spaces is necessary to minimize silverfish. This pest, however, is one of the most difficult insects to totally eliminate, even for a professional company.


Silverfish live in cracks and voids and are commonly found in larger numbers in attics, basements and crawl spaces. They are also common outdoors in southern states. Homes with cedar shake roofs seem to experience more serious infestations of silverfish. This may be due to the additional molds that form on this type of shingle. More available food results in more silverfish. Inside, silverfish will be seen occasionally or on a regular basis in kitchens, bathrooms and other rooms.


Tips for Control

Silverfish can be very difficult to control, especially in those homes that have wood shake (shingle) roofs. Shakes hold moisture and permit surface molds to grow, which serve as food for silverfish. Shake roofs are also very difficult to treat completely — to reach all the areas where silverfish can possibly live. In addition, silverfish often live in the soffits and behind the fascia board behind gutters. Individual silverfish then invade the interior of the home from this "reservoir" site. Compounding the problem in attics is blown-in insulation that prevents a professional from safely venturing into the attic to look for silverfish harborages. A professional should be consulted when silverfish are a regular problem. Areas that may require treatment include:

  • Voids where plumbing is located.
  • Voids behind electrical outlets.
  • Molding around windows and doorways.
  • The attic, crawl space and basement.
  • The soffits.

Silverfish Resources