Rats and mice do not stop at the walls of a single flat. In a building, a problem that starts in one home can quickly involve the whole block. Hence a recurring, tension-filled question: who has to act, and who pays? Here is how to make sense of it.
Recognising the signs in shared housing
In an apartment building, rodents move through the common areas before entering people's homes. Several clues should raise the alarm:
- scratching noises in the walls, false ceilings or service ducts, especially at night;
- droppings along skirting boards, in cellars, bin rooms or on landings;
- gnaw marks on cables, packaging or the bottom of doors;
- a persistent urine smell in cellars and crawl spaces.
These signs often appear first in the common areas: bin rooms, cellars, car parks, service risers. That is a strong signal: the source of the infestation is rarely limited to a single flat.
Who does what: tenant, owner, building manager
The split of responsibilities follows a simple logic tied to where the problem comes from.
- The tenant must keep their home in good order, maintain good hygiene and report any rodents promptly. A clear lack of upkeep may fall to them.
- The owner is required to provide decent housing, free of pests. If the infestation comes from the building fabric — cracks, networks, construction defects — treating the home is their responsibility.
- The building manager, representing the co-ownership, organises rodent control in the common areas: cellars, bin rooms, risers, basements. This is often the decisive level, because that is where the source points sit.
In practice, an infestation in a building is rarely solved flat by flat. Coordination between occupants, owners and the manager is the key to a lasting result.

How it spreads between flats
Rodents use the building's invisible pathways: electrical ducts, water risers, rubbish chutes, false ceilings, expansion joints. A 2 cm hole is enough for a rat, a little less for a mouse. Treating a single flat therefore just moves the problem: the rodents take shelter with the neighbour, then come back once the treatment is over.
That is why effective rodent control traces the source rather than settling for the visible symptoms. You have to identify the entry points, the nesting sites and the routes, then treat and seal them in a coordinated way across the whole building.



