Mayfair Office Building: Mice on Vacant Floors

Mice were living undisturbed on the empty upper floors of a Mayfair office building and spreading down to the occupied floors. We traced their routes, sealed them and added the vacant floors to the building's regular visits.

Sector: Offices
Area: Mayfair
Pest: Mice
Work: Survey, proofing, baiting and trapping

Empty floors are a gift to mice. In this Mayfair office building the top two floors were vacant, and with no one around to disturb them, mice had settled in and were starting to cause problems on the occupied floors below.

What we found

Mouse droppings across the floors of the top two vacant storeys
Signs of mice in the riser cupboard, where missing panels gave them a route between floors
Heavy smearing and a large number of droppings in the roof void
Droppings in the kitchen
A hole into the floor void, gaps around cables and gaps under the radiators

What we did

The building was already under a BioWise service contract, so we extended our routine visits to cover the vacant floors too. Alongside that, we:

Proofed the gaps and holes with a combination of pest-proof materials, including the floor void and the gaps around cables
Replaced the missing riser panels, so mice can no longer travel between floors
Set up baiting and trapping, including treatment of the roof and floor voids
Worked alongside our maintenance engineer to open up areas such as under the radiators, so every gap could be reached and sealed

The outcome

With the routes between floors sealed and the vacant floors now checked on every routine visit, mice can no longer settle undisturbed upstairs and work their way down to the occupied offices.

Why it matters in offices

Vacant floors, risers and ceiling voids connect a whole building. Treating only the floor where staff report mice rarely solves the problem: the mice retreat to the quiet areas and come back. Finding where they are living and how they move between floors is what makes treatment last.

Mice in London offices

Mice are one of the most common problems in central London offices. Shared risers, raised floors and ceiling voids let them move freely between floors, and sometimes between neighbouring buildings. Our mouse control combines proofing with discreet baiting and trapping, and regular visits keep an eye on the quiet areas where problems start, such as vacant floors, plant rooms and kitchens.

Not sure whether you have mice or rats? Our guide to mouse vs rat droppings can help, and our article on mice in the office covers the early signs to look for. We cover offices across Mayfair, the West End and the City of London.