Can Carpet Moths Spread From One Room to Another?

How It Spreads at All

Adults fly — badly. They flutter low, prefer running to flying, and rarely cross a house in one go. But they will move through an open door, along a hall, and up a stairwell over time, and each female lays eggs where she lands.

Larvae hardly travel. They stay in the area they hatched in unless conditions force them out, which is why damage stays localised for so long before appearing anywhere else.

What Actually Moves Them Faster

Being carried. Moving a rug from one room to another. Storing an infested wool blanket in a different cupboard. Relocating furniture that has larvae on its underside or in its base. Second-hand rugs and furniture brought into a house.

And vacuuming badly — a cylinder left full of eggs and larvae, emptied indoors or carried between rooms. Empty it into a sealed bag and put it in the outside bin.

Continuous Carpet and Underlay

Where a carpet runs unbroken from a landing into a bedroom, or up a staircase, the larvae can move along it without ever crossing a bare threshold. That is the commonest route between rooms upstairs.

Old felt or hair underlay running under multiple rooms does the same thing beneath the surface, and it is the reason a problem sometimes appears in two rooms that share nothing visible.

How to Find Out Which Rooms Are Involved

Check every room with a wool or wool-mix carpet, working around the edges and under the furniture, not the middle. Prioritise the rooms nobody uses: spare bedrooms, box rooms, a formal dining room, a landing.

Pheromone traps are useful here — not as a control but as a survey. Put one in each candidate room for a fortnight and see which fills. It is the cheapest way to find out where the population actually is before moving furniture.

Treating the Right Rooms

Treating one room while an adjoining one is untreated is how people end up doing this twice. It is £180 for the first room and £60 for each additional one, so adding a room at the same visit is far cheaper than a separate job later.

Between visits, vacuum the room edges and under the furniture in every room, not just the affected one, and move heavy furniture once or twice a year. Undisturbed is the condition they need, and it is the one thing entirely in your control.