How They Get Between Floors

A converted house was built as one home. The floorboards between your flat and the one below are usually the original timber, with gaps along the joists, and the pipes and cables were threaded through later. Bedbugs walk. They follow those gaps, the pipe runs behind the skirting and the voids around a shared chimney breast.
They move mostly when something pushes them: a treatment in one flat, a spray from a shop, or a room left empty so there is nobody to feed on. That is why a problem in a conversion is rarely just one flat's business for long.
Signs It Is Coming From Next Door
- Bites or bugs appearing after you had a clear run, with no new furniture or travel to explain it.
- Spotting or bugs along the skirting on a party wall or around pipework, more than on the bed.
- A neighbour mentioning bites, a treatment, or a mattress left out by the bins.
- Your own problem coming back after it was treated properly.
None of these proves it on its own. An inspection looks at where the activity is heaviest, which usually says whether it started in your bedroom or arrived through the building.
Treating a Flat When the Neighbours Have Them
Treating one flat in a shared house works, but it is harder to make it stick when the source is still active on the other side of the floor. The most reliable approach is for the affected flats to be treated in the same period, so nothing simply retreats into the flat that was left alone.
Heat suits a single flat well because it kills eggs as well as adults, usually in one visit. It leaves nothing behind, though, so in a conversion we would normally put a light residual along the skirtings and around pipe entries afterwards. Chemical treatment leaves that residue as a matter of course, over two or three visits. Why bedbugs come back after treatment goes further into it.
Talking to the Freeholder and the Other Flats
If the building has a freeholder or a managing agent, tell them in writing. The lease and the cause decide who arranges and pays for work in the common parts or other flats; we do not give legal advice on that. We can inspect more than one flat on the same visit and write up what we find in each, which is often what gets everyone moving.
A short, factual note to the neighbours tends to go down better than an accusation. Nobody chose to have bedbugs, and the flat that owns up first usually gets it sorted soonest.
If you rent your flat rather than own it, the landlord needs to hear about it in writing as well; the page on rented flats and studios covers that side. For the wider picture across the borough, including larger houses that have not been split, see the Bromley page.
Bedbug Control Beckenham — Questions
Can bedbugs come through the floor?
They cannot chew through anything, but they walk through the gaps that old floors and pipe runs already have. In a converted house those gaps are common.
Should the flat below be treated too?
If they have signs, yes, ideally in the same period as yours. If they have none, an inspection of their bedroom is a sensible check.
Is heat or chemical better in a converted flat?
Either can work. Heat finishes in one visit and kills eggs; in a shared house we usually add a light residual at the edges afterwards because heat leaves nothing behind.
How much does treating a flat cost?
Treatments start from £220, and the final figure depends on the number of rooms and on heat or chemical. We give it on the phone before booking.
Should I move into the spare room until it is sorted?
Usually not. Sleeping in a different room tends to take them with you, and it can push the ones left behind to look for a meal elsewhere in the house.
Elsewhere in Bromley
The other areas in the borough, each written around a different situation.
Bedbug Advice for Beckenham
Picked for this page: the guides that go further on what matters for Beckenham.

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Hatching, survival or re-introduction. Three different problems that look identical.
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HMOs and Serviced Apartments
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How Heat Treatment Works, and Does It Kill Eggs?
What heat actually does to a bedbug, and why an egg has no defence against it.
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Selling or Letting After Bedbugs
Getting it finished and on record before a sale, a let or a move.
Read more →Bedbug Treatments in Bromley
Every service has its own page for Bromley: heat, chemical, hotels, commercial premises and inspections.
Covering Beckenham
Tell Us About the Property
Tell us which floor you are on and whether any other flats in the house have mentioned bites, and we will suggest where to start in your Beckenham conversion.