Silverfish in the Home: Causes and How to Get Rid of Them

Silverfish (Lepisma saccharina) are among the most ancient insects on earth, having existed virtually unchanged for over 400 million years. They are well-adapted to life in human buildings and, once established, can be difficult to eliminate without professional help.

What Do Silverfish Look Like?

Silverfish are small (10–12mm), wingless insects with a distinctive silvery, metallic appearance and a fish-like wriggling movement. They have two long antennae and three bristle-like tails. They move very quickly and will dart into crevices when disturbed.

Where Are Silverfish Found?

Silverfish prefer cool, damp, dark environments with high humidity. In London homes, they are most commonly found in:

- Bathrooms and toilets - Kitchens, particularly under sinks and around dishwashers - Loft spaces - Behind boilers and water heaters - Behind skirting boards and under floorboards

What Damage Do Silverfish Cause?

Silverfish feed on starchy materials and can cause significant damage over time:

- Books and documents — they consume the starch in the binding glue and paper - Wallpaper — they eat the paste behind wallpaper - Stored foods — flour, oats, sugar, pasta - Photographs and art — damaging irreplaceable images - Natural fabrics — linen and cotton in storage

What Attracts Silverfish?

The primary attractant is moisture. Buildings with inadequate ventilation, persistent condensation, leaking pipes or rising damp provide ideal conditions. A silverfish infestation is often a signal of an underlying moisture problem that should be addressed.

Treatment

Professional treatment involves residual insecticide applied to skirting boards, cracks and crevices, combined with insect dusts in roof spaces and sub-floor areas. Addressing the underlying moisture conditions is essential for long-term control.

Seek an assessment from a suitably qualified pest professional.