About Woodlice (Porcellio scaber & Oniscus asellus)

Activity: Silent Nighttime Foragers

Woodlice are nocturnal crustaceans, not insects, that are most active at night. During the day, they hide in dark, damp places to avoid desiccation. Their activity peaks in humid and moist conditions, typically in spring and fall. Outdoors, they play an essential role in breaking down decaying organic matter, but indoors, their presence can be a nuisance.

While they do not bite, sting, or spread disease, their presence indoors often indicates excess moisture problems that can lead to bigger pest issues.

Diet: What Woodlice Eat & Why It Matters

Woodlice are scavengers and decomposers, feeding primarily on:

• Decaying plant material and wood

• Fungi, algae, and lichens

• Rotting leaves, mulch, and compost

Indoors, they may feed on moldy wood, damp cardboard, paper, and even spoiled food debris. While they cause minimal direct damage, their presence highlights underlying moisture and mold issues that should be addressed.

Size: Small, Armored Crawlers

Adult woodlice measure 10 mm to 15 mm in length. Distinctive features include:

• Flattened, oval-shaped bodies

• Hard, segmented exoskeletons resembling armor plates

• Two prominent antennae and seven pairs of legs

Their slow, lumbering movement and tendency to curl up when disturbed make them easy to recognize.

Nesting Habits: Where Woodlice Live

Woodlice require moist environments to survive, as they breathe through gill-like structures. Common habitats include:

• Under rocks, logs, mulch, and leaf litter outdoors

• Basements, crawl spaces, and poorly ventilated rooms indoors

• Bathrooms, laundry rooms, and areas with plumbing leaks

• Wall voids or floor spaces near damp foundations

Indoors, their presence is a sign of excess humidity, leaks, or poor drainage.

Why Professional Treatment Is Crucial

While woodlice themselves are harmless, their presence indoors indicates excess moisture, which can attract more destructive pests like silverfish, termites, and mold growth.

Professional pest control can:

• Identify and address moisture issues contributing to infestations

• Eliminate entry points and environmental factors favoring woodlice

• Apply targeted treatments where necessary to reduce populations

DIY methods often overlook the root cause—humidity control and structural repairs.

Signs of a Woodlice Infestation

Early Detection = Moisture Problem Solved

Look for these common indicators of an indoor woodlice issue:

• Sightings of Live Woodlice: Especially in damp areas like basements, bathrooms, and near drains.

• Clusters Around Foundations: Outdoor populations gathering near entry points.

• Moisture Stains & Mold Growth: Discoloration or soft spots on walls, floors, or ceilings.

• Damp, Decaying Wood: Soft or rotting wood near plumbing fixtures or basement walls.

Understanding the Problem: Woodlice Infestations Indoors

An indoor woodlice infestation is less about the pest itself and more about the environmental conditions allowing them inside. Persistent moisture problems can lead to structural damage, mold infestations, and attract more serious pests.

Over-the-counter sprays offer only temporary relief. Without fixing the underlying humidity and entry point issues, infestations will persist.

Our Professional Approach to Woodlice Control

We take a holistic approach to solving woodlice problems by addressing both the pest and the environment:

 Thorough Moisture & Pest Inspection

• Identifying water leaks, ventilation issues, and structural vulnerabilities.

• Locating key harborage sites indoors and outdoors.

 Integrated Control Plan

• Sealing cracks, gaps, and foundation entry points.

• Applying residual treatments in problem areas.

 Humidity & Prevention Solutions

• Recommendations for improving drainage, ventilation, and moisture control.

• Long-term strategies to keep your home pest-free.