The work will see the addition of a new balcony in place of the current portico
The Old Vic has submitted plans for a major revamp to Lambeth Council, including an artist's impression of how it will look.
Plans, which have been drawn up by Bennetts Associates, include repairs to the roof and the replacement of the portico on the front of the theatre with a large balcony.
The new building will include a new performance studio and workshop space, to be housed in what is currently the Waterloo Bar & Kitchen.
"Our proposals are designed to subtly retain and restore the much loved character of this grade II listed building, whilst the interior reconfiguration and extensions will unlock valuable space," said Simon Erridge of Bennetts Associates
The total cost of the scheme is in the region of £30 million, and is considered urgent.
According to the plans, "The roof leaks and may collapse if we don’t act soon, we lack front-of-house facilities audiences have come to expect elsewhere, and we’re in danger of losing the ability to attract creative talent if we don’t upgrade facilities backstage.
"We need to provide a home for our community, education and emerging talent work, and it’s vital that we offer all-day spaces so the Theatre belongs to everyone."
See Also: Our photos from last night's 24 Hour Plays gala at the Old Vic