Can Mice Travel Between Flats in the Same Building?

The Routes Between Flats

Service risers running the full height of the building. The boxing around the soil stack, which passes through every floor. Voids between floors and ceilings. Party wall cavities. Ducting and extract runs. And the gaps around cable and pipe penetrations at every floor level.

None of that is visible from inside a flat, and none of it requires a mouse to cross a communal space. A mouse can move from the ground floor to the third without going outside or passing a single door.

The Communal Areas That Feed Them

Bin stores are the single biggest factor in most blocks. Refuse chutes and the chute room below. Plant rooms and meter cupboards. Cycle stores. And the corridors themselves, where bags get left out overnight.

A bin store with a food supply and a gap into the risers will supply mice to every flat on the stack indefinitely, no matter what happens inside any one of them.

Why Your Flat Alone Is Often Not Enough

Treatment removes the mice in your flat and closes the gaps you can reach. If the building keeps producing them and the riser is still open at your ceiling, numbers recover.

That is why we say up front, before taking a booking in a block, when we think a single-flat treatment will hold and when we think it will not. It is a less comfortable conversation and it saves people paying twice.

What Is Still Worth Doing in Your Own Flat

A good deal. Seal the internal penetrations you can reach: under the sink, behind the boiler, the soil stack boxing, the gap at the extract vent, the threshold under the front door, and any hole where a cable enters. That reduces traffic in even while the building is untreated.

And have the flat treated — £190 — with the follow-up included. Even where the building is the source, an untreated flat is worse than a treated one.

What to Put to the Managing Agent

Ask for a building-wide inspection rather than flat-by-flat call-outs, attention to the bin store and chute, and sealing of the service penetrations at each floor. That last item is usually the cheapest single intervention available and the one most often skipped.

Be specific in writing. "There are mice" gets one contractor sent to one flat. "Droppings are concentrated at the riser cupboard and the soil stack boxing, which indicates movement through the service voids between flats" gets a different response. Ask neighbours too — people in blocks routinely assume they are the only one.