Replicating nature's beauty in stone
The Bexar County Public Works building in San Antonio, TX utilizes local natural stone to complement the surrounding scenery
Located in San Antonio, TX, the Bexar County Public Works building was designed to mimic the natural environment, having its physical presence and placement along the river act as a metaphor of the varied landscape. As San Antonio straddles the Balcones Escarpment, it creates the picturesque Hill Country rising out to define the West with the iconic San Antonio River at its heart. The limestone facade of the Bexar County Public Works, supplied by Keller Material Inc. out of Mesa Grande Blocks, was designed to appear to grow out of the sloping ground west of the river, utilizing the limestone from the Balcones Escarpment it imitates. The building was also oriented to reflect the bend in the river upon which it resides, replicating the river’s natural beauty in structural form.
“For the outside, limestone served as the literal foundation for Bexar County Public Works and also the inspiration for the rest of the exterior’s materials pallet,” said Angel Garcia of Marmon Mok Architects. “Complementing the exterior limestone, the outside also features weathering steel, zinc metal panels, glass and wood composite accents. For the interiors, the same limestone was used. In many places, the exterior wall continues seamlessly into the interior, creating a solid mass of stone that becomes focal points throughout the building.” According to Garcia, the stone was an essential design element throughout the Bexar County Public Works building because it signifies strong ties to the region, culture and history. Limestone is a defining element throughout the San Antonio region because of the many local quarries, resulting in a unique “Hill Country” style of light-colored natural stone exteriors used on everything from the UNESCO World Heritage Site Spanish Missions along the River, to new homes in the Hill Country.
“Because the building is a Public Works building, we utilized an abstracted map of the major county roads as a design motif throughout the building in different applications,” said Garcia. “The most visible ones can be seen from the river as a shading canopy and on the front of the building as a perforated screen that is illuminated at night. The abstracted map is also featured as a wall mural in the lobby, as adhesive decoration on conference room windows and through the use of carpet tiles.”
The same Sisterdale Old Yella limestone was employed both inside and outside. The wall veneer is 12 inches high x 4 inches deep x 10 inches, 20-inch and 3-inch lengths in 20% buff and 80% yellow. The Sisterdale Old Yella limestone veneer was supplied by I-10 Stone Source. The stone is carried from outside to the inside through the main lobby of the building, and is also featured in several other predominate places throughout the space — making a visual tie between the exterior and interior design.
Mesa Grande Quarried Limestone Landscape Retaining Blocks, measuring 2 feet high x 2 feet wide x 4 feet long, were used to tier down the slope and to enhance the illusion of the building growing out of the embankment. They were also used as benches on the front of the building. “Choosing this particular stone ties in with the natural palette of the area and other architectural elements of the region,” said Garcia. “Including shading structures along the river, Mission Concepcion Sports Park across the river, and most importantly, the nearby historic Missions.” A total of 15,100 square feet of limestone veneer was utilized for the 35,840-gross-square foot area.
One of the most challenging aspects of the stonework was determining the correct percentages of color range. “It was difficult to make sure we had the right mix of yellow stone to keep a random, but consistent mix of color,” explained Garcia. “Another challenging aspect of the stonework was having the stone span large openings, structurally carrying the stone over a 30-foot-wide window. We also hung the stone in soffit applications — having stone hanging from a structure spanning approximately 25 feet.” The project finished in 18 months.
According to Garcia, “Since the completion of the project, there has been an overwhelmingly positive reaction. Not only from Bexar County Public Works staff who are enjoying their new, modern and highly-functional space, but also from the public as the Bexar County Public Works building has increased visibility of the Mission Reach sector of the River and the communities/businesses that reside along it.”
Bexar County Public Works
San Antonio, TX
Architect: Marmon Mok Architects, San Antonio, TX