Posted: 7-21-2016, 2:28 p.m.
by Adolfo Pesquera
San Antonio (Bexar Co.) – Conceptual approval of the design for the 23-story downtown tower and future Frost Bank headquarters was granted Wednesday by the Historic and Design Review Commission.
A gargantuan exercise in origami-with-glass, the design was well explained by William E. Butler, a principal at Pelli Clarke Pelli, a New Haven, Connecticut firm that has designed some of the most iconic buildings in New York City and San Francisco, as well as in the Far East.
“By tapering towers so that the walls slope, it actually has a series of diminishing effects that make it appear more graceful,” Butler said. “The folds begin to increase as the tower ascends. And with the folds, greater corner offices are created and the form becomes more dynamic. Each of the facets lean ever so slightly. They become more pronounced as they terminate against the sky.”
Butler said the design borrowed from elements of the Emily Morgan Hotel and the Tower of Life. From the Emily Morgan, he noted how its triangular design comes to a point at Alamo Plaza with its faceted point. From the Tower of Life, he pointed to how it tapers to a point as it rises.
Unlike those buildings, Frost Tower will not have a masonry exterior. Attempts in recent times to use masonry on that scale have not been aesthetically successful due to the expense, he said. He defended the use of insulated glass panels, which he described as state of the art, adding, “The economics of what it takes to build at this level of aspiration occur only in certain cycles.”
Commissioner Tim Cone eventually got around to acknowledging that the panel “wholeheartedly” support the design. But on the way to admitting that, Cone, vice chair Michael Connor and Commissioner Daniel Lazarine made clear they had more rigorous expectations of what the project would look like at street level.
While Lazarine pointedly said there should be some yet to be revealed “grand gesture” in terms of how the tower would connect to the pending San Pedro Creek improvements project, Connor and Cone remained unconvinced there was enough of a transition to distinguish the ground level from everything above.
The main transition, Butler said, was the lack of reflection material in the glass at ground level. The upper floors are reflective for energy efficiency purposes and give the building a crystalline blue hue. At street level, the glass has warm colors and transparency, allowing passersby to see into a grand lobby.
Connor also challenged the project owners, Frost Bank and Weston Urban to build taller. At about 385 feet, the tower would be the sixth tallest downtown skyscraper.
The tower will be 400,000 square feet and include retail along Houston and Cameron streets. Cameron runs parallel to San Pedro Creek. Irby Hightower of Alamo Architects, the local design partner, said Travis Street would be relied upon as the service entrance for a parking garage and retail tenants; Travis Street serves the same purpose for buildings that front Houston Street.
The tower is designed to direct pedestrian traffic in an east-west direction. While one prominent entrance faces San Pedro Creek, the other entrance faces the pocket park owned by Frost Bank that is bounded by Houston, Flores, Travis and Main.
The Pelli Clarke Pelli summary states, “The site strategy is to place passive uses such as the office tower lobby on the park to the east, and active uses with retail on the western side adjacent to San Pedro Creek. This results in taller massing towards the park and the Central Business District and lower massing along San Pedro Creek to enhance the pedestrian environment envisioned.
“A prime goal of the project is to reinforce the promenade along W. Houston Street from the Alamo to Milam Park. The project capitalizes on the use of San Pedro Creek and neighborhood pathways to create a great pedestrian environment that connects to nearby cultural institutions, downtown parks, and historic sites. The new urban environment highlights San Antonio’s varied presence in tourism, finance, and technology.
“Retail activates the W. Houston Street promenade with direct access to outdoor plazas and seating under the grand allèe of live oak trees. A goal of the project has been to actively encourage pedestrian circulation along W. Houston Street connecting the city center to the historic Alameda Theater and reinforce the pedestrian environment along San Pedro Creek.”
At the corner of North Flores Street and West Houston, one of the octagonal tower faces provides a plaza entrance with tower access. The Houston Street side will be occupied by a retail tenant with access to an outdoor terrace for seating. At the base of the six-story parking garage on Houston, a continuous retail environment is integrated with the landscape.
Two distinct pedestrian pathways parallel to Houston: one wide path beneath the canopy of live oak trees and another along the sidewalk edge. Perpendicular paved pathways tie directly into projected glass retail bays that have canopies above the doors. Retail occupants will have the ability to place street furniture on these paved entryways to animate the pedestrian environment.
The Houston Street sidewalk is being interspersed with parallel parking and live oak trees. The integration of outdoor public space adjacent to retail will mitigate the heat island effect, providing comfortable spaces for gatherings and urban wildlife.
“The project has worked closely with the San Pedro Creek Redevelopment Team to create an integrated public response to the western facade. Retail runs from corner to corner along the Camaron Street facade adjacent to a sidewalk that is planted with live oak trees. An entrance to the garage has been narrowed from three lanes to two lanes and reduced in height to allow only automobiles to enter,” the architectural summary continues.
“The tower enclosure is a high-performance glass curtainwall system that optimizes energy performance while creating Class A office space with panoramic views of the city. The slightly reflective curtainwall system meets the International Energy Conservation Code of 2015. The enclosure’s performance shades 50 percent more sun than clear glass, is 75 percent more energy efficient than clear glass, and screens 82 percent more ultraviolet radiation than clear glass. Overall, the curtainwall system allows for 70 percent less heat energy infiltration than clear glass and creates a building which conserves energy and optimizes performance, symbolizing the values of Frost Bank and the City of San Antonio.”
The tower has three distinct facade zones. The base contains the lobby, retail bank, and commercial retail, and can be viewed as a glassy pavilion within a park. This zone in the building is clad in transparent glass with internal sunshades above to allow a visual connection for pedestrians looking in and for occupants looking out to the landscape.
“The middle of the tower is a series of octagonal shimmering facets, which enclose the shaft as it tapers towards the top of the tower. The crown cuts a silhouette against the sky, making it unique within the core of San Antonio. Integrated night lighting will utilize LED pin-striping at the edges of the tower form that will enhance the tower’s presence in the skyline of San Antonio.”
The design team will need to return to the HDRC for final approval, once the designs are at least at 80 percent of completion.