Can bed bugs travel between flats?

Bed bugs cannot fly or jump, but they are good at walking, and a block of flats gives them plenty of routes. If you live in one of Manchester’s city-centre apartment buildings, a converted Victorian house split into flats, or a council tower block, a neighbour’s problem can become yours. Here is how it happens, how to tell whether it is happening to you, and what actually stops it.

How bed bugs get from one flat to another

Bed bugs spend most of their lives hidden within a few metres of where someone sleeps. They move further when they are disturbed, when food runs short, or when the population grows crowded. In a building, they follow the same paths that pipes, cables and draughts do.

Through the walls and floors

Wherever a pipe, cable or duct passes through a wall or floor, there is usually a gap around it. Bed bugs are about as thin as a credit card when unfed, so a gap of a millimetre or two is enough. Plug sockets on party walls, the space behind skirting boards and gaps under floorboards in older conversions are common routes.

Along shared corridors

Bugs can leave a flat under the front door and walk along a corridor carpet to the next door. This is less common than spread through walls, but it happens in heavily infested buildings, and it is one reason managing agents sometimes treat corridors as well as flats.

In riser cupboards and service ducts

Modern apartment blocks have vertical risers carrying pipes and cables from floor to floor. These connect flats above and below each other, so a problem on the fifth floor can turn up on the fourth or sixth.

On people and belongings

Furniture carried through a stairwell, a mattress dragged to the bins, a neighbour’s laundry bag or a visitor’s coat can all carry bugs. Moving infested furniture out through shared areas is one of the most common ways a building’s problem grows.

What makes spread more likely

Bed bugs in a neighbouring flat will not necessarily reach yours. The risk goes up when:

• the infestation next door is large. Crowding pushes bugs to look further for food.
• the neighbouring flat is empty. With nobody to feed on, bugs wander. A flat left empty between tenants is a common source.
• someone uses shop sprays or foggers. Many products irritate the bugs without killing them, and they scatter into walls and next door.
• only one flat is treated. If the source flat is treated and the flats around it are not checked, survivors in the walls can come back.

Signs they are coming from next door

You may suspect a neighbour if bites start without any obvious trigger, such as travel, a new lodger or second-hand furniture, or if you find signs near a shared wall rather than around the bed first. Look for:

• small dark spots, like ink dots, on the skirting, around sockets or along the edge of carpet on the shared wall side
• live bugs or pale shed skins near radiator pipes or where pipes enter the room
• bites that continue after your own bed and sofa look clean

The NHS lists the main signs to check for: bites, blood spots on sheets, dark droppings on the mattress, and the bugs themselves.

What to do if your neighbour has bed bugs

Tell the right person

In a rented flat, tell your landlord or letting agent in writing. In a managed block, tell the building manager or managing agent. Councils and housing associations should be told directly if they are your landlord. One flat cannot fix a building problem, and the person who manages the building is the one who can arrange checks in the flats around the source.

Check your own flat regularly

Every few days, check the seams and piping of your mattress, the joints of the bed frame and headboard, and the sofa. Use a torch. Catching a few bugs early is far cheaper than treating an established problem.

Make your bed harder to reach

Pull the bed a few centimetres away from the wall, keep bedding off the floor, and consider interceptor cups under the bed legs and a bed bug encasement on the mattress. None of these will stop an infestation, but they make one easier to spot early.

Do not spray

It is tempting to spray along the shared wall. Shop sprays rarely reach the bugs inside the wall and can drive them further into your flat.

How a building is treated properly

The British Pest Control Association code of practice describes the approach professionals use in multi-occupancy buildings: inspect the affected unit and the units next to it, above and below, treat every unit where bugs are found, and monitor afterwards.

In practice, that means:

1. the flat where the problem started is treated, with heat or a spray course
2. the flats sharing walls, floors and ceilings with it are inspected, and treated if needed
3. riser cupboards and corridors are checked and treated if signs are found
4. monitors are left in place and a follow-up check is booked

A managing agent arranging treatment for several flats at once usually gets a lower price per flat. Heat suits a single flat that needs clearing quickly, but in a block where neighbours have bugs too, technicians often add a residual spray along the edges of the room to catch anything that comes back through the walls.

Who pays

If you rent, a problem spreading through a building is the landlord’s or the building owner’s to deal with, not yours. A serious infestation can make a flat unfit to live in, and the government guide for tenants explains what landlords in England must do. Keep a record of when you reported it and what happened.

If you own a leasehold flat, check your lease and talk to the managing agent: shared areas are normally the freeholder’s responsibility, while the inside of your flat is yours. Getting everyone treated at the same time is in everyone’s interest.

If you are in Manchester and need a technician who knows apartment blocks, our inspection page explains what a check of your flat and the shared walls involves.