How to Stop Bed Bugs Spreading Between Rooms

What Actually Crosses a Doorway

1. People, and what they are carrying. By an enormous margin the main route
2. Bedding and clothing being moved to a machine or a basket
3. Furniture moved during a clear-out
4. A host who has changed rooms, drawing them across over weeks
5. The insects themselves, walking. Genuinely last, and slow

Four of those five are behaviour. That is why the seven rules a household follows matter more than anything you can put across a doorway.

The Measures People Ask About

Interceptor cups under the bed legs — genuinely useful

Shallow plastic cups that sit under each leg, with a rough outer wall they can climb and a smooth inner wall they cannot. They do two real jobs: they stop insects reaching the bed from the floor, and — more usefully — they are a monitor, because anything caught in them tells you the room is still active.

They only work if the bed is genuinely isolated: nothing stored underneath, no bedding touching the floor, and the bed not against a wall it can be reached from. That is a lot of conditions, and it is why they are more useful for monitoring than for protection.

Sealing under the door — largely pointless

A draught excluder or a rolled towel across the bottom of a door does very little, because they are not queueing at the door. It does not stop the routes that matter and it gives a false sense of having done something.

Plastic sheeting over doorways — no

It is theatre, it makes a room unusable, and it does not address a single one of the five routes above. Occasionally it is part of a specific treatment method — in which case you will be told — but as a DIY containment measure it achieves nothing.

Encasements — useful, different purpose

A zipped bed bug proof encasement seals a mattress and base so nothing can establish in the seams. That is containment of an item rather than of a room, and it is worth doing after a treatment rather than instead of one.

Contain the Room, Not the House

The instinct is to protect the rest of the property. The more effective framing is to keep everything inside the affected room until it is dealt with — which is the same thing said the right way round, and it produces better decisions.

• Things you remove during preparation stay in the room
• Drawers and their contents stay in the room
• The bed does not get stripped on the landing
• The affected room is where you sleep, not where you avoid

Pangbourne: How Long Containment Has To Last

Until you are told otherwise, which normally means through the treatment and any follow-up. That is the awkward part — these are unpleasant instructions to follow for weeks rather than days.

What makes it bearable is knowing why: every one of them prevents a specific, expensive, and very common outcome. Ask what the timeline is when you book, so it is a defined period rather than an open-ended one.