The station was granted listed building status in 2004. As a result, a Listed Building Application is required in addition to the usual development rights associated with the historic Acts of Parliament in order to undertake improvement works at the station. Transport for London therefore intends to make a Listed Building Application to the Royal Borough of Kensington & Chelsea in early summer 2016, to obtain consent for a series of station capacity improvements.
The Listed Building Application will seek permission for the following changes:
- Rebuilding the disused platform on the north side of the District and Circle line, which will increase station capacity by providing dedicated eastbound services
- A new contemporary canopy will be constructed from glass and steel, to allow the historic revetments to be seen
- New stairs from the ticket hall will be added along with a shaft for the installation of a lift from ticket hall to platform level at a later date. A matching lift shaft will be added to the current island platform
- A new overbridge will be added to provide a route from the Piccadilly line subway to the new platform via the island platform. The overbridge will also provide a route to a new emergency exit to the road bridge leading into Thurloe Square
- An enlarged ticket hall and centralised gateline, created by removing offices and relocating ticket machines
Taken together, these improvements will add a considerable amount of space to the interior of the station to help address the current pressure on the station.
At a later stage these improvements will allow for the 45-year-old escalators to be replaced.