Why are There Silverfish Under My Sink?

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Silverfish may not be harmful to your health, but they can chew through your favorite things. And besides, an infestation of the pest is just gross! One of the places they like to infiltrate is underneath sinks.

Because they’re often found here, as well as around drains in sinks and bathtubs, or around floor grates, many have concluded that silverfish come into the home via wastewater in sewage pipes. However, this is a misconception, as they don’t travel in water but rather crawl along the outside of plumbing pipes in search of food in the deposits that form under air extraction vents and drains.

Attracted to moisture and warm, dark places with levels of humidity above 75 percent, they frequent bathrooms for their favorable environment. However, because they can’t climb on smooth, vertical surfaces, they end up trapped in bathtubs and sinks.

To keep silverfish from taking over your sinks and bathtubs, you should remove moisture as quickly as possible. You should repair leaky faucets and use a dehumidifier to remove moisture before silverfish become active. Outdoor precautions can be helpful too. Check that water drains away from your home and that your gutters and downspouts are free of debris.

Blocking off common access points, including cracks under and behind baseboards, as well as around windows and door trim can keep silverfish from entering your home. If you find any cracks, use caulk to seal them. Vacuuming carpet, floors, upholstered furniture, cracks and crevices can remove any young and adult silverfish.