The new theatre radically alters the space by lowering the stage level by 2.8m and remodelling the auditorium and stage. The increased height allows the introduction of new technical installations, including stage suspensions and a lighting bridge, as well as a steeper seating rake, which improves the focus of the room. Extensive structural alterations have been required to underpin the existing structure and remove existing columns in the stage area. Existing dressing rooms have been improved and a new goods lift installed serving the stage. A new displacement ventilation system, with plant at roof level, improves audience comfort and acoustic performance and meets the requirements of current technical standards.

A minimal but rich palette of materials has been used to finish the space, with board marked concrete, stainless steel, maple panelling and purple bute fabric to the seating. The resulting detail of the new theatre pays homage to the solid materiality of the National Theatre and the Barbican, buildings that are contemporary with the original American School complex.