Why chimneys attract wasps and hornets
A chimney stack is warm, sheltered and full of gaps: where the stack meets the roof, around the flashing, under the pot. Queens explore these in spring, and a disused chimney is especially inviting because nothing disturbs it.
European hornets also favour chimneys and hollows nearby. If very large wasp-like insects are using the stack, particularly towards dusk, they may well be hornets. We treat both for the same £125.
Signs the chimney is the way in
Watch from the ground. Wasps arriving at the stack and disappearing around the pot or flashing, every few seconds, means the nest is close. Indoors, you may hear them in the chimney breast or find them in the fireplace of an unused room.
Wasps occasionally fall down the flue and emerge drowsy in the fireplace. If this keeps happening, the nest is almost certainly in or beside the chimney.
- A steady flight line to the stack or pot
- Buzzing or rustling in the chimney breast
- Drowsy wasps appearing in the fireplace
- Activity continuing into the evening: possibly hornets
Never light a fire under a nest
The old advice to "smoke them out" is dangerous and useless. A fire under a live nest drives angry wasps down into the room, and nest material in a flue is a fire risk in itself.
Do not block the top of the chimney or seal the fireplace while the nest is active either. Trapped wasps find another way out, and it will be into your house.
How we treat a chimney nest
Access matters with chimneys, so we assess it first. Where the entrance can be reached safely, we treat it directly and the returning workers carry the treatment to the nest. If the nest is in the roof void beside the stack, we may treat from inside the loft instead.
We will always discuss access with you before starting, and there is no call-out fee for that conversation. One nest is £125, fixed, with the free revisit if it stays active.
Once the chimney nest is dead
A dead nest in a flue or void will not be reused and can be left alone. If nest material has fallen into the flue, a chimney sweep can clear it in winter.
Fitting a cowl or cap to a disused chimney in winter keeps out next year’s queens, and the birds too.
Chimney nests: common questions
Wasps keep appearing in my fireplace. Is the nest in the chimney?
Very likely, or in the roof void beside the breast. Keep the fireplace blocked off loosely with a board or screen so they cannot enter the room, and call us.
Can you treat a nest without scaffolding?
Usually. Many chimney entrances are reachable with our access equipment, and some are treated from the loft. We will tell you honestly on the phone what your chimney needs.
Are hornets in the chimney more dangerous?
European hornets are larger but not more aggressive than wasps unless the nest is disturbed. They are treated the same way, for the same £125.