The National Maritime Museum (NMM) has launched a redevelopment tender for the Royal Observatory Greenwich, with work expected to start in early 2026.
The planned scheme, estimated to cost up to £42m, will be delivered in two phases across the south and north sections of the UNESCO World Heritage Site in south east London.
Phase one, focused on the south part of the site, is due to begin in January 2026.
The north section is expected to remain open to the public until late 2026 before it will be closed for the temporary removal of occupants and contractor mobilisation.
Phase two works are expected to follow in early 2027 and last until early 2028, although precise timings are to be confirmed during the tender process.
The Grade I-listed Greenwich Park and “several listed buildings” fall within the scope of the project, the NMM said in a tender notice today (7 April).
The observatory is also designated as a Scheduled Ancient Monument.
The masterplan aims to preserve the Observatory’s heritage while enhancing its function as a science centre and tourist destination, the NMM said.
Planned new-build elements include an entrance pavilion, a garden walk, an elliptical stair to the Grade I-listed Great Equatorial Building, and a new “science engagement space” linking the Planetarium and South Building.
A café kiosk and new lifts will also be added.
The scheme includes conservation work to existing structures, including roof and window replacements and facade repairs.
The site’s gas heating system will be replaced with air source heat pumps as part of a wider programme of decarbonisation.
Responses to the tender notice are due by 6pm on 5 September 2025. The estimated contract value is £25m to £35m excluding VAT.
An award decision is expected by 31 October 2025.
Source: Gov.uk Find a Tender