Last November Lambeth councillors approved plans to redevelop the site with 55 luxury homes and 14 affordable flats.
Now the development – known as 'Palace View' – has been bought by Taylor Wimpey for more than £30 million.
Matt Sharman from Levy Real Estate, which advised RER on the sale, said: "There was tremendous interest in the site.
"It provides a great opportunity to develop a landmark building in an area where values continue to rise".
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