How to deal with silverfish infestations at home

Silverfish are among the more secretive household pests in Australia. They don’t bite or spread disease, but they can damage paper, fabric, books, and even wallpaper. If left unchecked, a silverfish infestation can quietly spread through cupboards, basements, or roof cavities.

This guide explains how to recognise silverfish activity, why they infest homes, and the best ways to reduce their presence using practical methods and professional support.

What are silverfish?

Silverfish are small, wingless insects with a flattened, elongated body and distinctive, fish-like movement. They are silver-grey in colour and typically measure between 1 and 2 centimetres long. Silverfish are nocturnal and prefer dark, humid spaces.

These pests feed on starches and sugars, often found in paper, glue, textiles, and even pantry items. They’re particularly drawn to damp areas like bathrooms, laundries, and poorly ventilated storage rooms.

Because they hide during the day and move quietly at night, silverfish infestations often go unnoticed until damage is spotted.

What causes silverfish infestations?

Several conditions can attract silverfish into Australian homes:

• High humidity and moisture: Leaky pipes, poor ventilation, or wet towels left in bathrooms.
   
• Cluttered storage areas: Cardboard boxes, stacks of newspapers, and books provide ideal hiding spots.
   
• Warmth and darkness: Silverfish prefer temperatures between 20°C and 25°C and areas with limited light.
   
• Food sources: Starch-rich materials like paper, wallpaper glue, and some clothing fibres attract silverfish.

Once inside, they can live undetected in cracks, behind skirting boards, inside cupboards, or under flooring.

Signs of a silverfish problem

Silverfish are elusive, but there are telltale signs of their presence:

• Yellow stains or small holes in clothing, wallpaper, or pages of books
• Feeding marks such as irregular notches along paper edges or fabric
• Droppings that look like black pepper grains
• Shed skins as silverfish grow
• Live sightings, often at night when turning on lights in dark areas

Bathrooms, kitchens, and storage spaces are common areas where silverfish signs appear. Even new homes can be affected, especially if construction or insulation leaves gaps or creates damp zones.

Why silverfish are hard to control

Silverfish are hardy, fast-moving, and capable of surviving for months without food. Their flattened bodies allow them to slip into tiny gaps, and they can live unnoticed in walls, ceilings, and furniture.

They lay eggs in hidden areas like crevices, cracks, and folds of fabric, making infestations hard to detect until they’ve spread. Their nocturnal habits also mean that homeowners may not realise they’re present until items are damaged.

This combination of stealth and resilience makes silverfish difficult to remove using basic methods alone.

How to reduce silverfish activity at home

Dealing with silverfish requires a mix of good housekeeping and targeted control. Here are practical steps to support your home’s defence:

1. Control humidity

Silverfish thrive in humid environments. Use the following methods to reduce moisture:

• Fix leaking taps or pipes
• Use exhaust fans in bathrooms and kitchens
• Air out wardrobes and cupboards regularly
• Use a dehumidifier in closed, damp areas

2. Improve storage conditions

Cluttered storage spaces are ideal for silverfish. Keep your belongings organised by:

• Using plastic containers instead of cardboard boxes
• Sealing books and important documents in storage tubs
• Rotating stored items to prevent long-term build-up
• Keeping linen and clothing clean and dry before storing

3. Maintain clean surfaces

Clean surfaces with fewer crumbs remove silverfish food sources. Regular cleaning tasks should include:

• Vacuuming skirting boards, corners, and behind furniture
• Wiping down cupboards and pantry shelves
• Removing old papers, magazines, and boxes from storage

4. Seal entry points

Check for cracks, gaps, and other entry routes. Common spots include:

• Around pipes and plumbing under sinks
• Behind skirting boards or wall edges
• Gaps around windows and doors

Seal these areas with caulking or weatherproofing materials where possible.

Why professional treatment is often necessary

While basic maintenance helps, established silverfish infestations typically require professional intervention. Rentokil technicians are trained to identify infestation zones and apply targeted treatments based on the severity and location of activity.

Treatment may include:

• Residual sprays in cracks, crevices, and behind cupboards
• Dusts and gels in roof voids or inaccessible areas
• Monitoring stations to track ongoing activity
• Advice on moisture control and exclusion strategies

Professional treatment is particularly important for homes with recurring infestations, large numbers of stored books or clothing, or buildings with older construction.

Why silverfish are common in Australian homes

Australia’s climate supports silverfish activity year-round. In coastal cities like Sydney, Brisbane, and Perth, higher humidity levels increase the chance of infestations. In cooler regions like Melbourne or Canberra, silverfish tend to be more active indoors during winter as they seek warmth and shelter.

Silverfish are often more noticeable after rainfall or during seasonal changes, when moisture levels fluctuate and trigger movement from hidden areas.

Suburban homes with older timber features, poor ventilation, or enclosed roof spaces are at higher risk. However, modern buildings are not immune, especially if they use cardboard insulation or have complex wall cavities.

What to expect from a professional silverfish treatment

A typical silverfish treatment by Rentokil includes:

1. Inspection – Technicians inspect high-risk areas including bathrooms, laundries, roof voids, and stored goods.
    
2. Identification – Silverfish species and infestation extent are confirmed.
    
3. Treatment plan – Based on the findings, appropriate insecticides are applied to active zones.
    
4. Ongoing monitoring – Where needed, technicians may return to monitor treatment success.
    
5. Prevention advice – Practical tips are provided to help reduce the chance of future infestations.

Silverfish treatments are tailored to your property, taking into account the structure, local conditions, and severity of the problem.

Conclusion

Silverfish may not cause immediate concern like rodents or cockroaches, but their quiet activity and ability to damage valuable items make them a frustrating pest to deal with. In Australian homes, especially those with high humidity or poor ventilation, they can thrive in hidden corners, wardrobes, or ceiling spaces.

Dealing with silverfish effectively involves controlling moisture, reducing clutter, and sealing off hiding spots. When infestations persist, professional treatment is the most effective solution. With the right support and practical steps, you can reduce silverfish activity and protect your home’s contents over the long term.