UK-based Haworth Tompkins has received approval from the local council for the renovation of the National Theatre in London, UK.
The alterations and additions, approved by Lambeth Council, include moving the main entrance, bookshop and stage door, greening the terraces and opening up the concrete walls with glazing.
Other changes include moving the service area and adding a new paint studio building on the south side.
The committee resolved to grant planning permission following agreement over safeguards on interior flooring and outdoor paving.
Work is expected to start late next year and is set to be completed by 2013, according to local sources.
The project's committee was met with opposition from architectural historian William Curtis who had come from France to plead for the late Sir Denys Lasdun's original designs to be respected as a guideline for any change.