Moth Damage

A moth infestation can strip a wool rug to its foundation in a single season. Nothing else in ordinary domestic life destroys rugs that fast.

What is actually eating it

Not the moths. Adult clothes moths do not feed at all — they mate and lay eggs. The damage is done by the larvae, which eat keratin: the protein in wool, silk, hair and feathers.

Two common textile pests are Tineola bisselliella, the webbing clothes moth, and Tinea pellionella, the casemaking clothes moth. Their larvae favor dark, undisturbed and soiled — because soiling provides the additional nutrients the larvae need alongside the keratin.

That is why rugs get eaten under sofas, along the edges against walls, and above all in storage.

The signs

Frass: Fine sand-like grit, the colour of the wool it came from
Webbing: Silky tubes or matted patches on the pile surface
Bald patches: Pile lifts away cleanly, leaving bare foundation
Larvae: Small cream grubs, 5–10mm, often inside silk tubes
Adults: Small buff moths that run and flutter rather than fly well

Check under the furniture, not the open floor

Moths avoid light and traffic. The open middle of a rug is almost never where it starts. Lift the rug and look underneath, look under every piece of furniture standing on it, and check the edges against the wall — twice a year.

An adult moth alone does not tell you whether larvae are feeding in this rug. Use the active-damage checklist to distinguish current evidence from an old bare patch, and remember that carpet beetle larvae can cause similar damage.

Stopping an active infestation

Act immediately; larvae eat continuously.

Isolate the rug. Take it out of the room so the infestation does not spread to other wool textiles.
Vacuum thoroughly, both faces, paying particular attention to the base of the pile and the edges. Empty the vacuum outside immediately.
Have it professionally washed. Immersion washing kills eggs and larvae and removes the soiling that attracted them. This is the definitive step — DIY vs professional.
Ask about controlled freezing for a suitable small item. Time and temperature depend on the protocol and the textile; do not assume a home freezer will treat a valuable rug safely or completely.
Treat the room, not just the rug. Vacuum the floor beneath, the skirting and any upholstery.

Pheromone traps catch adult males and are useful for monitoring whether you still have a problem. They do not solve an infestation on their own — the larvae are already in the rug.

Repair afterwards

Moth damage is repairable on a hand-knotted rug: the affected area is repiled knot by knot, or rewoven if the foundation has gone too.

It is priced by area, so catching it early is the difference between a small job and a large one. See rug repair.

On machine-made and hand-tufted rugs there is nothing to repair into.

Prevention

The single most effective habit is disturbance. Moths need undisturbed conditions, so moving the rug, vacuuming under furniture, and rotating twice a year prevents most infestations from establishing.

Beyond that:

Never store a rug unwashed — soiled wool is what attracts them. Rug storage.
Vacuum the reverse twice a year, and under furniture rather than around it.
Inspect twice a year, lifting the rug and looking underneath.
Cedar and lavender are mildly repellent and lose potency; refresh annually and treat them as a supplement rather than a defence.

Wool's vulnerability here is the counterpart to everything else it does well — see wool rug properties and wool rugs: pros and cons.

Every guide in Moths

All 1 article in this section, starting with the ones we would hand someone new to it.

Is the Moth Damage on Your Rug Active? — start here

Common questions

How do I know if my rug has moths?

Look for fine sand-like grit (frass), silky webbing or tubes on the pile, patches where pile lifts away cleanly leaving bare foundation, and small cream larvae. Check under furniture and along walls — moths want dark and undisturbed.

Do moths eat synthetic rugs?

Not the fibre itself. Clothes moth larvae eat keratin, so wool, silk and hair are at risk and synthetics are not. A blend can still be damaged where the natural component is, and soiled synthetics can host larvae feeding on the residues.