Design-Build Team Performs New Take on Halls Classic Space
In theater, updating a classic can be a delicate process as one tries to retain the flavor of the original while making it relevant for a contemporary audience. The same approach applies to the design and construction of the new Tobin Center for the Performing Arts in San Antonio. The project aims to retain the historic facade of the city's existing hall, known as Municipal Auditorium, while creating performance spaces that meet present-day demands.
The original auditorium featured a 1926 Spanish Colonial Revival-style street front that is a prominent part of the city's historic core, but the structure's interior performance spaces no longer fit the program needs of the community. The design team, led by Seattle-based LMN Architects, with Marmon Mok Architecture, San Antonio, worked closely with a joint venture of Linbeck, Houston, and San Antonio-based Zachry Construction, to strike a balance that would satisfy the community while holding to the project's $200-million budget.
"What we have is a historic building that is treasured in the community," says Mark Reddington, LMN partner. "The question was, how can you preserve and restore this historic building and transform it into something that meets the contemporary needs of a performance venue?"
The resulting 183,000-sq-ft design retains the auditorium's street-front facade, which is tied into a modern and highly flexible performance facility that can accommodate a wide range of users. The team plans to wrap up its 30-month construction schedule in May 2014.
Paul Sipes, senior project manager at Linbeck, says the design-build team modeled numerous design studies to strike the right balance. He says that one critical decision was to retain not only the facade, but a complete bay of structure behind it.
"Because we didn't have to leave a facade and rip out the structure, the process wasn't that delicate," he says. "We don't have a 70-ft-tall wall that needs support with temporary structure."
Behind the historic portion, crews demolished the existing performance hall, much of which had been updated over the years and had limited historic value, Reddington says. The historic concrete and steel structure entry way, which sits on spread footings, is designed to tie into a new steel structure set on 50-ft-deep piers. An open lobby space between the two buildings helps accommodate variations in floor heights.
To create dramatic new spaces while remaining sensitive to the budget, LMN designed the new building with a mix of relatively simple geometries and then wrapped it in a sweeping "veil" of metal panels to provide dramatic dimensions to the exterior. The veil will have an upward flow, extending out as it rises up the building. The veil's panels have voids to allow light through and protruding pieces that will create dynamic shadows that will shift throughout the day.
Of equal importance to the building's historic front on its south elevation is the structure's north elevation, which borders the city's River Walk along the San Antonio River. The original auditorium used this side primarily as a loading dock. With the new design, the team saw an opportunity to blend the building with the river spaces.
Because the city grid does not meet perfectly with the flow of the river, the designers shifted the orientation of the new structure slightly to the north, keeping the historic facade aligned with the street while the back of the facility aligns to the river. New landscaped spaces will be created along the river side, improving the flow between the two.
To further blend in with the River Walk, the veil will feature numerous LED lights that can change colors and sparkle at night.
"If you go on the River Walk at night, you see that there are lots of colored lights and accent lights that transform it into an almost theatrical experience," Reddington says. "This design respects that. The veil itself has no direct lighting, so it will fade into the shadows, leaving only the accent lights to appear at night. It transforms this large object into a series of sparkling lights."
In addition to blending with exterior elements, the design is also created around stringent programmatic demands. Because flexibility was paramount, the main performance space is built around a unique movable floor system. The floor, designed by Gala Systems, Quebec City, Quebec, is a series of 36-in.-wide mechanized rows that can be lifted and lowered independently to create a wide variety of room configurations. Seating rows can be lifted and flipped 180 degrees to tuck away the seats and create a flat floor surface.
As a result, the room can be configured in multiple ways, including a traditional stage with flat-floor seating or stadium-style seating. The floor can also be raised to stage level with or without seating. The rows are raised and lowered by a series of spiral lifts, not hydraulics, reducing the chance of an oil odor. This is also critical because the facility's air conditioning flows through the floor system.
In addition, barrier walls can be lifted from the floor to restrict access to certain areas. Rows can also be grouped to create a stage lift for loading purposes. A single operator controls the entire system using a handheld device. Configuration changes take less than 10 minutes to execute. While the system has been used in Canada, this will be its first use in the U.S.
Because the system allows different floor levels, designers had to create public accesses at various levels to match those potential configurations, Reddington says.
The balcony fronts also help transform the space. Each is clad in wooded boxes that are perforated for inset LED lights. Those lights can change color and create patterns to fit user demands. "You could use a golden wood tone for a symphony or heat it up to bright red for a rock show," Reddington adds.
To properly install the variety of systems required for such a space, the design-build team went through an extensive coordination process using building information modeling. The design team's initial concepts, created in 2009, were executed using Bentley software. But the construction team uses Revit software, so the models were converted around the time when the design document phase was completed.
"Once we got to a 100% [construction documents] model and the 100% CD conformed set model, we were able to use that model and then purchased an auditing service to make sure the final translation matched," says Becky Burleson, client executive at Linbeck. "We found that was about 90% correct, so we then cleaned up and validated that remaining 10%."
Burleson says every major subcontractor is contractually required to model its work to prescribed levels of development. "Some had the in-house capability and some had to purchase that service, but there was no option for key trades to not do that," she adds.
Sipes says that because of the vast open space, there is often complicated and circuitous routing systems throughout the building. "Comparing it to a hospital project, it's not as enormous of a space, but [it is] equally challenging," he adds.
Through BIM modeling, the team also expects subs to emphasize prefabrication and just-in-time delivery of system elements. Pipes will be welded off site, requiring only bolting in the field. Materials for steel erection, which is currently under way and scheduled to top out in November, are limited to one day of storage on the ground before erection. The veil system, which is made up of approximately 15,000 individual pieces, will be built on a metal stud framing system that will be preassembled in approximately 10-ft by 30-ft panels, trucked to the site and lifted into place. "That takes a task that would have taken a week per elevation down to a two-day process," Sipes adds.
The intense early coordination through modeling should greatly ease challenges in the field, helping to maintain a tight schedule, Sipes say. He adds that the biggest milestone on the horizon is enclosing and finishing the bulk of the performance space before installation of the movable floor system, which Gala Systems will entirely self-perform starting in fall 2013.
"That installation is on the critical path," he says. "The heavy construction all needs to be done. Everything is focused on meeting that milestone."
