Economy and utility of design

Press, Volume CXII, Issue 33034, 29 September 1972, Page 23

Economy and utility of design

A technical summary of the Town Hall’s features brings into focus the economy and utility of design.

Visitors will pass through the central entrance block containing concourses, bars and a large meeting room, and turn either towards the auditorium or in the opposite direction towards the theatre, or continue through to the restaurant and banquet hall.

The auditorium seats 2400. It is oval in plan with two levels of promenade serving a series of entrances into the main auditorium space.

Here there are two levels of seating surrounding the stage in a layout designed

to be as flexible as possible. The stage includes three adjustable sections mounted on electrically driven screw-jacks; when lowered these enlarge the floor, making it suitable for large floor shows.

The internal dimensions of the auditorium are height 70ft, and length 144 ft. Its structural system consists of a series of reinforced-concrete flanged walls around the space, with secondary frames outside these supporting the upper promenade.

Steel roof trusses support precast concrete slabs covered with a lightweight screed and butynol. The upper gallery is supported on cantilevered frames, and the lower seating tiers are framed in timber on to the

timber ground floor. Beneath this is a tanked concrete slab and field tile drainage system as the ground water level is at floor level.

The auditorium is the first major hall in the world to incorporate model studies in its constic design, resulting in precisely defined reflector panels supported on the walls and hung from the ceiling.

The theatre is specifically designed for stage productions. It has two levels of seating holding approximately 1000, and a 65ft high fly tower. Its construction is basically reinforcedconcrete frames supporting steel roof trusses and a precast concrete roof and concrete walls. The fly tower has blockwork walls and a 2in plycopyne roof. Surrounding dressing rooms and storage areas are separated from the

stage by sound-proofed doors; both levels of seating are novel in being open to the internal concourse behind them. The restaurant and banquet hall, and the entrance block, are also reinforcedconcrete frames supporting precast floor systems and timber trussed roofs. The associated kitchen block is a complicated concretewalled building of three storeys plus basement. These buildings hang over the river in part.

Fairface concrete is used extensively in the building, and considerable efforts were made in preparing the formwork and controlling the site-mixed concrete to consistently attain the design surface. Contrasting elements of fabric and stained-timber panels, and marble and copper produce a rich finish.

The whole building is equipped with sprinklers and is air-conditioned. Airconditioning is provided by three heat pumps and a heat exchanger mounted in the River Avon. The auditorium and theatre each use twin major air-handling units. Supplementary heating is provided by two electrode boilers.

There is one central control point for the whole complex.