Carpet Beetles vs Carpet Moths - What's Damaging Your Carpet?

Tell It by the Larva

This is the reliable test, because the larva is what does the damage in both cases and the two look nothing alike.

Carpet beetle larva: short and stout, about 4 to 5mm, banded light and dark, covered in bristles, curls up when disturbed. Often called a woolly bear. Carpet moth larva: a smooth pale caterpillar, frequently inside or dragging a silky case the same colour as the carpet. Bristly and banded means beetle. Smooth and pale means moth.

Tell It by the Damage

Moth damage is one spreading grazed patch with a soft edge, thinning the pile towards the backing over a continuous area, in a place nobody walks.

Beetle damage is scattered — several small distinct holes in different places, damage along the seams and folds of stored clothing, bare threads on the underside of a rug. One patch that is growing is moth. Several separate holes is beetle.

Tell It by the Adult

Adult carpet beetles are small, rounded and mottled, like a very small ladybird without the colour, and in spring they head for the light — so they turn up on windowsills, often in an upstairs back bedroom.

Adult carpet moths are small and buff coloured and they do the opposite. They run and flutter low near skirting boards rather than flying properly to a lamp. Beetles on a windowsill, moths near the floor.

Why the Answer Changes Where We Look

This is the part that matters. Carpet moth is usually a problem in the wool that is in the room — the carpet, the underlay, stored textiles — and the job is largely in that room.

Carpet beetle very often comes from above: a bird’s nest in the eaves, a dead bird in a chimney or soffit, or a loft holding old wool, feathers and bedding. Any of those keeps producing larvae indefinitely. Treating the carpet every spring without dealing with the roof space is a subscription rather than a solution, and that is the single most common reason a beetle problem keeps coming back.

Why the Answer Changes the Treatment

Different insects, different life cycles, different products and different places to put them. A treatment aimed at moth larvae in a carpet and underlay will not deal with beetle larvae feeding in a wardrobe floor and a loft.

Both are priced the same — £180 for the first room and £60 for each additional room — so the identification is not about the invoice. It is about whether it works. If you are not sure which you have, keep a couple of larvae or shed skins in a sealed clear bag and the technician will identify them on the day.