Text:/ Andy Ciddor

CURTAINS!

One of the more unusual features of the Sumner Theatre is the absence of that long-standing public health institution: the fire curtain. Provided as a safety measure to protect the audience to be from the once-fairly-regular conflagrations that would break out on stage, the concept was that this non-combustible fire curtain would be lowered in to trap the fire on stage, immolating the performers and crew, while the gentlefolk in the audience had time to flee from the auditorium.

To meet their onerous fire ratings, most fire curtains are constructed from a framework of steel beams covered with a non-combustible material such as metal, fibro-cement sheeting or even asbestos sheeting. Weighing several tonnes and occupying a slot some 150mm–300mm deep in the proscenium arch, these fire curtains are required to completely seal the gap between the stage and the auditorium. No scenery or props are permitted in the path of the fire curtain, and any mechanism to allow for adjustments to the proscenium opening must still maintain the critical fire seal.

Theatre consultant Dennis Irving sat down with the fire authorities in Melbourne and persuaded them to rethink the problem of audience safety. As the purpose of a fire curtain is to allow the audience to exit safely in the case of a fire, Irving proposed that by providing enough clear exit paths from the theatre, and using a stage ventilation system that prevents the smoke from a stage fire from entering the auditorium, there would be sufficient time for an audience to get safely out of the building without the need for a fire curtain.

By accepting Irving’s proposal, the fire authorities cleared the way for the design of a reconfigurable proscenium frame and freed set designers from having to leave a hole in their sets to accommodate the lowering of the fire curtain. Thus, unlike any other major theatre in the country, through some smart design by MTC and clever engineering by primary contractor Jands and Steve Conroy at ShowTrek Productions, the Sumner’s proscenium opening, complete with Juliet balconies, is variable in width from 11m to 16m, and also variable in height from 0m to 9m, while always looking like an architecturally-solid wall.

FLEXIBILITY

Because there is no such thing as a standard format for an MTC production, the venue has been designed from the outset to allow almost anything to be done, almost anywhere. While some of the possibilities for production, performance and events could be imagined and, even catered for directly in the plans, it’s clearly impossible to build in adequate facilities for the as-yet-unimagined requirements that will arise during the many decades that the building will be in use.

As the very model of a modern major production house, there are clusters of three-phase power, technical power outlets, data feeds and audio tie-lines secreted in every nook and cranny of the building; from the roof to the staircase landings, and from the workshops to the offices, the ceiling voids, and probably also in the cleaner’s cupboard.

Any place in the building where it is even remotely possible to want to hang anything – from a drape to a Christmas decoration, a length of rope, or couple of lights, to an advertising banner or a circus performer – you’ll find strengthened and rated rigging attachment points. Water, drainage and compressed air lines are run to the roof, all sides and levels of the stage house, everywhere you can imagine backstage, and of course the pit and all over the under-stage area. These are provisions for the unlikely and the unusual, but the nevertheless conceivable.

What happens if you need 200 Amps of 400Hz/110V power in the greenroom or a chilled glycol feed in the control room, a satellite antenna feed in the orchestra pit, a gas flame in the middle of the auditorium or half a dozen HD television camera feeds from the Lawler Studio to an outside broadcast van in the loading dock? How can you achieve these feats without compromising public access paths, fire isolation integrity, or performing serious building works?

The answer chosen by MTC, was to install a series of resealable ‘mouse holes’ in every internal wall, floor and ceiling in the building, enabling any space to be connected to any other space, using nothing more sophisticated than a short step ladder. In the photo you can see that the mouse holes are constructed from standard plumbing pipes and access covers. Fire isolation is maintained through the use of fire-rated bean bags packed with fire-rated pellets of equivalent value to the wall material. Once a cable, hose or pipe has been run through a mouse hole, the bean bags are re-packed into the hole to restore the fire isolation.

STAGE FLOOR

The stage floor of a performing venue is always a bitter bone of contention. Directors frequently want the ability to structure entrances and exits in the vertical as well as the horizontal plane. Stage designers love to explore every skerrick of the stage volume to create the space for the production, by using staircases and putting holes through the floor. Production managers and head carpenters, on the other hand, are always under time and budgetary pressure to have the stage available for fit-up and technical rehearsals. But making good the floor from a previous production, or installing floor traps for the next one, requires areas of the stage to be closed off for safety purposes and engages teams of carpenters and mechanists who could otherwise be involved in turning the venue around.

The solution devised by project manager Craig Gamble for the Sumner Theatre approaches the problem from the opposite direction: there is no permanent stage floor. In the manner of an IT room, the entire stage deck is constructed from easily demountable uniform modules that can be interchanged with pre-built replacement units with the necessary traps already in place. The make-good process simply involves replacing the modified floor module with a standard unit. All preparation and construction takes place off-site, with replacement modules interchanged at the start of the fit-up. While this may seem relatively simple, there were some stringent engineering requirements for ShowTrek during the development of the stage floor system to allow the floor to carry not only the large distributed weights of stage sets, but also the substantial point loads of self-propelled elevated work platforms, like the Sumner’s excellent 2.7-tonne Haulotte Star 10.

The only section of the stage floor that isn’t completely removable is the forestage, which consists of three independent lifts powered by Serapid’s LinkLift actuators. The lifts can be set at substage level to form an orchestra pit, at auditorium floor level to extend the seating capacity of the theatre, or at stage level to become a forestage. As the additional auditorium seating wagons are stored beneath the auditorium in the under-stage area, the lifts also serve to transport these seat units to their auditorium position.

FOLLOWSPOT BRIDGE

Although only a few of MTC’s productions use followspots, it was essential for the theatre to have followspot positions that provide both a safe working platform for the operators and a good lighting angle. Such a place is the bridge built on the level above the control rooms. In keeping with the brief for maximum flexibility in the venue, any point on the bridge can be used for followspots, special effects equipment, television broadcast or closed circuit video cameras, projection systems, musicians, or even as a performer’s entrance or balcony. Using a system developed by Jands, the entire wall between the bridge and the auditorium can be electrically raised or lowered in independent two-metre sections to create any arrangement of portals or slots in the rear wall. Of course, this bridge is supplied with all of the usual electrical, audio and data services, and is accessible through the mouse hole network and via staircase to the control room.

There is also a series of similarly cabled slots that can be opened as required in the side walls of the auditorium, to provide positions for lighting booms, loudspeakers, alternative followspot positions, effects equipment, projectors, scenery or even performers.

HOUSE LIGHTING

In addition to the conventional Source 4 Pars used for house lighting, the architect proposed to have sections of the walls of the auditorium display quotes from famous productions and playwrights. While the idea was enthusiastically accepted, the proposed display system – an array of addressable colour changing LED pixels spread across the upper parts of the auditorium walls – was fairly swiftly costed out of existence. When MTC were advised that the auditorium wall panelling had to be perforated in order to meet the acoustic requirements of the room, they implemented a traditional theatrical solution to create the so-called Word Walls. In place of a matrix of tens of thousands of LEDs, the words were created by drilling patterns of holes in sheets of 32mm plywood which were then mounted over the required sound deadening voids painted white inside. The void space of each wall panel is illuminated by a Space Cannon Athena RGB LED washlight to form a lightbox. The overall effect is virtually indistinguishable from the original concept and the colours of the words can be changed with ease. The one drawback is that short of replacing the drilled ply sheets, it’s no longer possible to change the wording.

TO INFINITY & BEYOND

Unlike its equally impressive next-door neighbour, the Melbourne Recital Centre [see Issue 4], that was built to host new productions with new requirements every few days, the MTC theatre building was built to house a specific company producing shows with complex requirements, and runs measured in weeks and months rather than days. The type of flexibility that has been incorporated into this carefully thought out building leaves MTC with a clear path forward into the unknowns of future technologies, scripts, designers and directors.