A lighting rig will be accessed via a series of bridges rather than the current system of technicians changing the lights by standing on a stepladder.

A fly tower will allow larger and more adventurous scenery to be used, while trapdoors will be able to be placed anywhere on the stage instead of just in two places, as in the existing arrangement.

Also key to the plans is a dedicated Youth Theatre space, returning the work of young people to the centre of the action, as it was when Liverpool-born actors David Morrissey and Cathy Tyson were members.

Ms Bodinetz added: “The addition of a dedicated space for our youth and outreach work, rehearsal room, writers’ hub, natural ventilation, full disabled access and 21st century technical facilities will mean this much loved theatre will live on in a physical incarnation which fits its national reputation and idiosyncratic personality.”

Offices and further rehearsal and studio space will also be included on a footprint which takes in the existing Everyman, 11 Hope Street next door and a newly-acquired slice of a car park behind the building.

In October 2008, Arts Council England, the North West Development Agency and the council identified the Everyman as the highest priority cultural capital project in Liverpool in response to an independent study commissioned by Arts Council England and funded by the NWDA. London-based architect Haworth Tompkins was chosen for the project in 2007.

The funding plan includes £15m from Arts Council England and £2.5m investment from the NWDA.

The balance is being sought from a combination of public sector sources, fundraising and appeals.

A revamp of the Playhouse theatre will follow.