What Are the Signs of Carpet Moth Larvae Around Skirting Boards?

Why the Room Edge Specifically

Nobody walks on it, so there is no disturbance. A vacuum head passes over rather than into it. And the carpet is held over a gripper strip, which creates a dark sheltered gap running the whole perimeter of the room.

On top of that, debris collects there — hair, skin flakes, fibre, dust — which is food. Undisturbed, dark, sheltered and provisioned is the complete specification for carpet moth larvae.

What You Are Looking For

Silky tubes or cases lying along the pile, the same colour as the carpet because they are made from it. They look like small grains of fluff until you look properly, and they are the most distinctive sign there is.

Then: fine sandy debris and frass along the gripper line, shed larval skins, and the larvae themselves — smooth pale caterpillars up to about a centimetre. And the pile thinning in the last few inches before the skirting.

How to Check Properly

Get down at floor level with a torch and work along the edge rather than looking from standing height. Run a finger along the join between the carpet and the skirting and see what comes up.

Where you can, lift the carpet edge off the gripper in a corner — a few inches is enough — and look at the underside of the carpet and the top of the underlay. Damage is frequently on the underside before it shows on the surface.

Where to Start

Behind and under the sofa, along the wall it stands against. Under and behind wardrobes and chests of drawers. The perimeter of any spare bedroom. Around the pipe holes where radiator pipes come through the floor. Under the edge of any rug laid over a carpet.

Do the rooms nobody uses first. A busy living room is the least likely place to find it and the first place most people look.

What It Means If You Find It

Cases and frass along the gripper line means an active population in that room, whatever the middle of the carpet looks like. It is a confirmation, not a maybe.

Treatment concentrates on exactly this strip, plus under the furniture, and is £180 for the first room and £60 for each additional one. Between visits, the crevice tool along that same line does more good than anything else you can do.