The Twentieth Century Society has disputed the Office for Metropolitan Architecture’s (OMA) plans to redevelop the Commonwealth Institute in Kensington.
The group has claimed the commercial property proposal would see everything other than the roof demolished.
Caseworker John Wright told Building Design there were a number of possibilities for the plot, which has yet to confirm an occupier.
“There’s scope for almost anything to happen,” he said. “What they’re pushing for is the demolition of everything apart from the roof. No conservation group would find that acceptable.”
OMA has proposed a £150 million redevelopment, which would include adding three residential blocks nearby.
Until a deal is struck with the new tenant no solution could be agreed, said Daniel Moylan, deputy leader of Kensington and Chelsea council.
The Design Museum hopes to move into the institute and is still discussing the details, Building Design has reported.
Developers can alter listed buildings, but as a rule they should not affect its character or lessen its interest, insurer NFU Mutual has advised.