De Matos Ryan – a London based architectural firm – has been granted planning permission to go ahead with a £4.1m revamp of The York Theatre Royal, UK, while nearby Newcastle's Theatre Royal is also getting a makeover, albeit behind the scenes.

After a large fundraising effort, the York project is now set to move forward with an onsite start date of March 2015 and a provisional completion date of December 2015.

The £4.1m scheme will extend the foyer spaces, revamp the auditorium with a new flexible stage system and new seating as well as creating an external contemporary street façade.

By enclosing the existing Victorian colonnade, a new main entrance will be made to allow easy access. The currently underused Georgian staircase will be brought back to life, facilitating access to the main auditorium from both sides.

The York theatre has occupied the site since 1744 and the refurbishment will uncover Medieval and Georgian elements that have been hidden some time as the establishment is the longest running theatre outside of London. The last significant changes that were made to the site was with Patrick Gwynne's 1967 extension – it has remained virtually untouched since.

Speaking to the Architects’ Journal, Angus Morrogh-Ryan, director at De Matos Ryan, said: "This project will unlock the theatre’s potential, opening their doors to a wider community… underpinned with a sense of resilience and sustainability."

The Newcastle Theatre Royal is also getting a makeover as part of a two phase process. The work will see the whole of the backstage area of the Newcastle theatre, transformed, following on from a £4.9m auditorium restoration that took place in 2011.

This will be the first time that the backstage area has had any form of intervention since 1988. The project, headed up by Newcastle based Mawson Kerr Architects, will aim to improve comfort, accessibility and facilities for visiting companies and their performers.

Will Mawson from Mawson Kerr, said that “the Theatre Royal is a stunning building and a fine example of a Matcham Theatre and so naturally we were excited to play a part in enhancing it for the enjoyment of future generations.”

Both historic buildings, the Newcastle Royal – opened in 1837 – and the York Royal – opened in 1744 – have undergone several refurbishments in their lengthy histories. The good news for theatre in England is that developments like this allow for evolution to take place, meaning that even outside of London, England’s theatres stand less chance of being neglected and falling into disrepair.