Carpet Moths Identification Greenwich: What Signs Should You Look For?

The Damage

What to look for: thinning, then bare patches, in wool carpet. The pile is grazed down rather than perforated, so the edges of a damaged area are soft and gradual rather than sharp. Backing may become visible where it is advanced.

Where: at the edges of rooms, under furniture, beneath rugs, behind doors that stand open, along the margins of a stair runner where nobody walks.

What it rules out: small, clean, sharply defined holes are carpet beetle. Wear from foot traffic is in the walked-on middle, which is exactly where carpet moth is not.

Silken Tubes and Cases

What to look for: small tubular cases in the pile, made by the larvae from carpet fibre and debris - which is why they are the same colour as the carpet and almost invisible until you know to look. Sometimes described as looking like a grain of rice made of the carpet itself.

What it tells you: confirmation. This is the sign that distinguishes carpet moth from everything else on a floor, and finding one is worth more than seeing a dozen adults.

The Larvae

What to look for: small, pale, cream to off-white and caterpillar-like, often partly inside a silken case and dragging it along. Smooth rather than hairy.

Where: in the pile at the edge of a room, under furniture, beneath a rug, in the gaps between floorboards.

What it rules out: short, bristly, banded larvae are carpet beetle - the hairiness is the giveaway and it is unmistakable once you have seen both.

Frass and Debris

What to look for: fine gritty material at the carpet edge and under furniture, usually the colour of the carpet. Frass, shed cases and fragments of damaged fibre.

What it tells you: active feeding. It is routinely vacuumed up as dust, which is one reason problems go unnoticed for so long.

The Adult Moth

What to look for: small, plain, buff to golden brown, and a weak flier. Tends to run, scuttle or flutter low down near skirtings rather than flying across a room, and prefers dark undisturbed places to lit ones.

What it tells you: that larvae are somewhere in the property. Nothing about where.

What it rules out: moths circling a light in the evening are almost certainly something that came in from the garden. Moths in a food cupboard are pantry moths. Neither eats carpet.

What They Will and Will Not Eat

The rule underneath the table: they feed on keratin, the protein in animal fibre. That is the whole of it, and it explains every row.

Carpet Moth, Clothes Moth, Carpet Beetle or Pantry Moth?

1. Carpet moth. Damage on the floor, at edges and under furniture. Silken tubes in the pile. Smooth pale larvae. Adults low down near skirtings.
2. Clothes moth. A close relative with the same appetite, but the damage is to stored clothing inside wardrobes and drawers. Many properties have both, and it changes where we treat rather than whether.
3. Carpet beetle. Small, clean, sharply defined holes. Bristly banded larvae that shed pale skins. Small mottled beetles on windowsills in spring.
4. Pantry moths. In dry goods - flour, cereal, rice, dried fruit, pet food. Webbing inside packets. Nothing whatever to do with carpet, and a completely different treatment.

Where to Look, in Order

1. Under and around any rug that has not been lifted recently.
2. The skirting line behind and beneath large furniture.
3. The strip of carpet behind a door that always stands open.
4. The edges of any room that is not in daily use.
5. Stair and landing edges, where the centre is walked and the margins are not.
6. Inside wardrobes and the airing cupboard, in case clothes moth is involved too.
7. Under a corner of the carpet, if the boards beneath are original and gapped.

Checking a Valuable Rug or Carpet

Worth doing properly and worth doing periodically, because with wool of any value the damage is done long before it is visible from standing height.

1. Turn it over. Damage frequently shows on the back before the surface pile looks obviously wrong.
2. Check the fringe and the selvedge edges, which are undisturbed even on a rug that gets walked on.
3. Look at the section under furniture if a piece stands on it - that part has been in the dark for as long as the furniture has been there.
4. Part the pile in several places and look at the base of the fibres rather than the tips. Grazing starts at the base.
5. Look for the tubes. They match the rug's colour, so use a torch at a low angle rather than looking straight down.
6. Check the floor underneath for fine debris and shed cases.

Do it twice a year on anything you would be sorry to lose, and move the rug occasionally between times. Undisturbed is the condition that matters.