A Jacobean mansion and a concert venue in a Baroque church are among 26 sites across London to be added to Historic England's at-risk register.
Charlton House in Greenwich, south-east London, was built in 1612 and repaired following damage caused in the Blitz, but a leaky roof is affecting its historic interior so it has been added to the register.
Twenty-five other sites have been removed from the list as they are now considered safe, such as Abney Park Cemetery in Hackney. Another place was cut after being reassessed.
It means there are now 599 sites across the capital deemed at risk of neglect, decay or inappropriate development by the heritage group.
Other sites added to the register include the Grade-I listed Smith Square Hall in Westminster.
Originally opened in 1728 as the Church of St John the Evangelist, the site was decommissioned as a church and became a concert venue in the 1960s following bomb damage during World War Two.
Historic England said "issues with the historic fabric urgently need to be addressed through a programme of repair work".
"Further works to services, including electrics, and improvements to space are also needed, to give the concert hall a thriving and sustainable future," it added.
Stoke Newington Town Hall, designed in art deco style by architect J. Reginald Truelove, was built between 1935 and 1937 but has remained vacant for several years meaning the space can no longer be used fully, Historic England said.
Its addition to the register "will help to ensure that essential repairs are carried out and focus given to finding sustainable new uses," the heritage body said.
Mayor of Hackney, Caroline Woodley, said: "We have a strong track record of protecting our heritage buildings.
"However, like many councils, we’re currently facing significant financial challenges.
"We hope this news will showcase the potential of the building as we continue to plan for its future use."
Historic England said it had awarded over £1m in grants for repairs to 11 sites in London during the last year.
Duncan Wilson, chief executive of Historic England, said: "Heritage is so important to London.
"It’s inspirational to see how we can harness the power of our heritage to benefit local people across London.
"Together, we can save our places and find new ways to enjoy the heritage that people value so much."