Chimney Stacks and Disused Flues
A queen that has come through the winter starts her nest somewhere dark and dry, then adds to it all summer with paper she makes from chewed wood. An unused flue gives her height, shelter and no traffic. The first thing anyone notices is usually sound rather than wasps: a dry rustling inside the chimney breast, loudest in the alcove cupboard beside it, or a few wasps appearing in the room with the blocked-off fireplace. Because the stack is shared, the flue the wasps are using may serve the house next door, which matters when it comes to access. Can wasps nest inside walls? covers nests you cannot see into.
Roof valleys, parapets and bay window roofs
Many of these terraces do not have a simple front-to-back slope. Two roof slopes meet in a valley gutter running back from the front parapet, with lead work and tile edges along both sides, and there are small flat or lean-to roofs over the bay and the back addition. Every one of those junctions has a soft spot: a lifted tile at the valley edge, a gap where a flat roof meets the brickwork, or the joint above the bay just under a front bedroom window. Where wasps build nests around houses runs through the rest.
Sheds, hedges and back gardens
Away from the house, the garden offers plenty. Nests turn up under the felt of a shed roof, behind stacked pots and folded chairs, deep in a boundary hedge, and in the ivy that grows over an alley wall. Compost bins and log piles are worth a careful look from a distance too. A nest in a hedge on a boundary is often found by whichever neighbour is doing the trimming, so it is worth saying which side the entrance is on.
Working Out Where They Are Going In
Pick a warm afternoon, stand well back in the garden or across the street, and watch for a minute. A nest reads as a steady two-way line of wasps using a single opening; wasps drifting round a bin or a fallen plum are just foraging. Note the height, and whether the opening is on the stack, the roofline, the bay roof or the shed, because that is what decides how we get to it. The signs of an active nest and telling wasps from bees help if you are unsure. Scratching and dragging above a bedroom ceiling at first light is not wasps at all but a squirrel, and winged insects boiling out of a paving crack on one sticky July afternoon are flying ants.
What not to do while you wait
- Leave the opening exactly as it is — capping a pot or filling a valley gap with wasps inside pushes them to find another way out, often into a bedroom or a loft
- Do not lean a ladder against a parapet or a bay roof to get a closer look
- Keep the windows on that side shut, particularly any window directly under the entrance
- Do not light a fire in a fireplace whose flue has wasps in it
- Keep children and pets out of the flight line across the garden or the front path
Booking a Wasp Visit in Willesden
Tell us where you think the entrance is and roughly how high, and how we reach the back — through the house, a shared side alley or a rear passage, and whether the alley gate is kept locked. If you are in a converted flat, say which flat is yours and which windows look onto the nest, and let the freeholder or managing agent know as well if the nest is on the roof or the stack rather than beside your own window. Anyone in the household who has reacted badly to a sting before should stay indoors and well away, and signs of a severe allergic reaction after a sting mean calling 999.
After the visit
Expect wasps around the entrance for a while yet; that is normal and not a sign nothing happened. Keep the nearest windows closed, leave the opening unblocked for now, and let the shed or the fireplace alone for a few days. A dead nest in a flue or behind a bay roof does not need cutting out, because next year's queens start somewhere new. Should the nest still be active within 30 days, we return at no extra cost — will wasps return after treatment? sets out what is normal in between.
Fewer Nests on the Roofline Next Spring
Nothing makes a Victorian roof wasp-proof, but a few jobs once the season is over shorten the list of openings. Our Brent wasp advice goes wider, Wasp Nest Removal Brent covers the rest of the borough, and neighbouring Harlesden has much the same roofs.
- Once the nest is dead, ask a roofer to cap or repair the flue you do not use, and to look at the pointing round the stack
- Have slipped tiles at the valley edges and the joint above the bay roof put right at the same time
- In April and May, look under the bay roof, along the alley wall and inside the shed for a small papery ball the size of a golf ball, and call rather than knock it down
- Keep the shed shut and shake out folded furniture before summer
- Lidded bins and cleared fallen fruit make the garden less interesting in late summer
