Royal Festival Hall

By 1964, some maintenance was required; ticket offices and a new entrance, backstage facilities and offices were added, and experimental solutions to the problematic acoustic proposed. In the late 60s, the Festival Hall was joined on the South Bank by several other cultural buildings including the Queen Elizabeth Hall, Hayward Gallery and Purcell Room. These additions served to substantially change both the hall itself and its context, and not always for the better.

An accretion of concrete ramps, walkways and service roads tangled the changes in level between the riverside and Belvedere Road making the area around the hall somewhere you wouldn't want to linger at night. Inside the building, foyers were clogged with cafes and retail while growing office accommodation for the Southbank Centre had been shoehorned in too. The building was full to bursting, impeding its ability to function as a concert hall and obscuring the original design intent.

Built as a classical concert hall for acoustic performance, by the 1990s about half of the performances at the Hall were amplified, exacerbating the acoustic challenge that had been an issue since the building's construction. In addition, the Hall's cultural programme now extended to dance, opera, spoken word, but access to the stage for scenery, large instruments and other kit was complex and time consuming to install, necessitating dark periods between productions.

The client brief was two-fold; restore the building but also upgrade it to better meet contemporary demands, both in terms of acoustic and production capabilities.

Inside the building, a series of works tackled the acoustic issues. The auditorium was stripped back to the original concrete box and all finishes fixed firmly to this to extend the reverberation time.

This graceful timber over-stage reflector designed by the original architects was seen by musicians and conductors as a major problem for the acoustic. So good was it at pushing sound from the stage to the audience that acoustic musicians and orchestras couldn't hear themselves play.

Creating a variable acoustic to serve the demands of acoustic and amplified music was also important. This required a mix of hard reflective surfaces balanced with absorbent fabric surfaces within the hall that could be employed as required. The stage geometry was altered and the project's acousticians helped inform the decision to replace the original plywood canopy with adjustable fabric reflectors which throw high frequency sound back to the stage immediately - giving precision, but are permeable to mid and low frequency sound - giving warmth.

The stage was re-configured and equipped with lifts that allow it to move in eleven separate sections; the choir benches can be wheeled out to provide a flat dance floor; and new lighting bridges suspended above the stage, give safe access to production equipment.

To increase audience comfort, the space between seat rows was extended by 75mm by rebuilding the concrete floor of the stalls, with a loss of only 118 seats. Cooling was introduced by reversing the airflow in the auditorium.

Extensive research informed the colour palette for the interior while the striking original 'net and ball' carpet by Moro, was lovingly recreated at the only remaining carpet factory in Wilton, Somerset. In fact, it was the sourcing of original materials that proved some of the most taxing tasks for the design team. How to locate replacement interior stone cladding from a Derbyshire quarry that had long since ceased trading? Or to source the quantity of English elm needed to restore the internal joinery?