A £500,000 funding application is being submitted to the Arts Council England to refurbish the interior of the historic St George's Guildhall.

This bid sits alongside the previously submitted Heritage Lottery Fund application for £2.7m for development and management of the complex on King Street. A decision on the bid is ecpected next month.

It would cover the cost of improvements including a new stage, lighting and heating in the building, which closed last year after the arts centre trust which ran it said it couldn't make it pay.

Proposals were presented to the user group at a meeting last week by Graeme McGinty of Charcoal Blue, a specialist theatrical innovation consultancy.

Elizabeth Nockolds, West Norfolk council's cabinet member for culture, said: 'We had a really good meeting and the user group were very happy with the overall proposals for the theatre. There were some interesting discussions around the best options for the seating, orchestra pit, stage and lighting, which we will incorporate into the bid, with some of the finer detail to be confirmed later.

'What was really pleasing was it was clear that everyone is behind this project and they all want to see the Guildhall and complex being used more effectively.'

King's Lynn Festival has pledged its support for the project along with Norfolk Museums Service. The museums service would program exhibitions and installations supported by the curatorial team based at Lynn Museum and the service's design and conservation departments, if the funding bids are successful.

Alison Croose, chair of the festival said: 'The celebration of the restoration of St George's Guildhall launched King's Lynn Festival in 1951 and the building – the largest surviving Medieval guildhall in England – continues to be a crucial and much-loved venue for a wide variety of Festival events.

'It is at the heart of Lynn Festival and we would be delighted to see its facilities updated so it can continue to provide an intimate setting with an excellent acoustic for a wide variety of events including smaller-scale classical music concerts as well as jazz and folk, speakers and films.'