U.S. Building of the Week
Balboa Park Pool
ELS/Kuth Ranieri Architects
16. December 2019
Photo: Bruce Damonte
Balbao Park, located in the San Francisco neighborhood of the same name, is full of recreational facilities: baseball diamonds, a soccer field, tennis courts, a playground, and an indoor pool. The last is housed in a concrete-and-glass building from the 1950s that was recently renovated by a joint venture of ELS Architecture and Urban Design and Kuth Ranieri Architects. They answered a few questions about the project.
Location: San Francisco, California, USA
Client: City & County of San Francisco
Architect: ELS/Kuth Ranieri Architects Joint Venture
- Design Principals: Clarence D. Mamuyac, Jr., FAIA, LEED AP BD+C; Byron Kuth FAIA, LEED, AP; Elizabeth Ranieri, FAIA, LEED AP
- Project Manager/ Project Architect: Susan Vutz, AIA
- Job Captain: Eliza Koshland
Mechanical Engineer: H&M Mechanical Group
Electrical Engineer: EDesignC
Landscape Architect: Miller Company Landscape Architects
Energy Modeling: Farber Energy Design
LEED Consultant: Urban Fabrick
Civil Engineer: Telamon Engineering Consultants
Aquatic Consultant: Civil Aquatic Design Group
Cost Estimating: Saylor Consulting Group
Specifications: Topflight Specs
Commissioning: Rick Unvarsky Consulting Services
Site Area: 42,000 sf
Building Area: 18,980 sf
Photo: Lawrence AndersonPlease provide an overview of the project.
Balboa Pool has been a beloved fixture of San Francisco’s Balboa Park neighborhood since it opened in 1956, with its natatorium, sleek horizontal form, flat roof, scored concrete-clad exterior walls, bands of metal-framed windows, extensive glazing, minimal ornamentation, exposed wood and concrete ceiling, and swooping semicircular ramp leading to the central entryway. Designed by noted architect Frederick H. Reimers, it is one of the only still-intact International-Style pool buildings constructed in the 1950s for the San Francisco Recreation and Parks department during the wave of construction of recreational facilities that occurred in the years immediately following World War II.
To renovate the facility after more than six decades of use, our joint venture design team preserved the pool’s historic character of the 1950s-era building while making essential repairs, upgrading structural and environmental systems, and enhancing the user experience for the 21st century.
Photo: Bruce DamonteWhat are the main ideas and inspirations influencing the design of the building?
The renovation of this mid-century pool represents an opportunity to catalyze its surroundings, spurring increased community participation and providing the neighborhood with an enhanced family resource.
The design for the pool renovation preserves the qualities of the original Brutalist structure while enhancing the user experience and upgrading the structural and environmental systems for a more sustainable facility. By reconfiguring the locker rooms and administrative spaces, the design team developed a new community room within the existing shell. A reconfigured entry and landscape create a fully accessible facility, improve the flow of traffic, and strengthen the connection to the community, making the pool a vital resource to be enjoyed by the community for years to come.
Photo: Lawrence AndersonHow does the design respond to the unique qualities of the site?
The parks department sought to add a community room that could be leased for meetings, receptions, birthday parties, and other events. This would bring revenue to help pay for operations while also providing an important gathering place for the community. Rather than house the community room in an addition, an expensive solution, the design team increased the pool’s programming capacity by reconfiguring the changing rooms and administrative spaces and carving out space for a new 800-square-foot community room accessible even when the natatorium is closed.
Because the 1950s pool was longer than regulation length for competitions, the designers divided the pool with a bulkhead that provides a regulation-length swimming area while also separating lane swimmers from recreational swimmers and swimming classes, enabling different groups to use the facility comfortably at the same time. The bulkhead also allowed the installation of stairs descending into the pool, making it safer for children to get into the water.
Photo: Bruce Damonte
The existing semicircular ramp was a distinctive part of the historic building but did not comply with ADA standards. The planning department’s historic preservation commission wanted the building to keep a portion of the ramp and maintain the overall gesture. The design team replaced one wing of the ramp with a staircase for quick access, retaining the curving shape, and replaced the other wing with a new curving ramp that met ADA standards. Even the original railing was replicated in a way that met ADA standards while preserving the historic appearance.
To better connect the facility to its neighborhood context, the parking area was redesigned to improve traffic flow, with a new drop-off area for parents to pick up waiting school children. A new civic threshold is created by defining a clear point of entry with a contemporary metal canopy and by integrating discreet landscape and lighting elements. Obscure glazing systems and metal grills were replaced with a transparent glazing system to give the building new transparency, opening the pool to views of the park and neighborhood beyond, and new supergraphics spell out the name of the pool at the building’s front façade, marking the building’s distinctive role in the neighborhood.
The rehabilitated pool preserves the qualities of the original building, while respectfully upgrading it to serve as a vital resource for the community for years to come.
Photo: Bruce DamonteHow did the project change between the initial design stage and the completion of the building?
The general core of design enhancements remained from concept through construction, but a handful of ideas, unfortunately, were not realized, as more investment was required for essential seismic upgrades.
To better connect the natatorium to the park immediately south, the design team created the “beach,” a series of terraces leading from the natatorium down to the park. Access to the terraces was via glass accordion doors – a Nana Wall system – spanning the full length of the wall and integrated with the new window wall system. Had it been constructed; it would have provided another opportunity for community programming. The hope is that the project will be retrofitted with this feature sometime in the future.
Photo: Bruce DamonteWas the project influenced by any trends in energy-conservation, construction, or design?
The project’s energy efficiency and environmental performance goals were to achieve a high-performing building on a very tight budget, and provide all new state-of-the-art, high efficiency HVAC and pool systems with minimal impact to existing historic building fabric and to the surrounding park.
Sustainable Design Strategies:
- RECYCLED BUILDING: The pool’s historic renovation was inherently sustainable. The building was retained and reused, thus saving energy in the manufacturing, transportation, and installation of new materials and in the disposal of demolished materials. As a renovation of a historic building, this project sought to retain as much of the existing building original fabric and materials as possible, including patching and repairing and of existing concrete walls and structural elements and preservation of the existing wood roof structure. Existing concrete shell and wood structure was preserved and revived. Minimal off-hauling and delivery of major materials for the project resulted in light carbon footprint.
- DAYLIGHTING AND VIEWS: New windows with high performance glazing provided unobstructed views of the Balboa Park neighborhood and hills beyond, while decreasing solar heat gain and glare.
- EFFICIENT LIGHTING: High efficiency lighting used throughout, with building control system to keep electrical use to minimum.
- IMPROVED INDOOR AIR QUALITY: New HVAC system with continuous fresh air supply improved air quality in the natatorium. Materials selected were low VOC.
- WATER SAVINGS: The project achieved a 45% reduction in water use by providing a reclaimed water system to take non-potable waste water from the pool dehumidification unit and use it for toilet flushing. Grey water collected from the natatorium dehumidifier is used to flush all toilets.
- NET GAIN GREEN: No existing green space was impacted for the project. Existing impermeable paving was reduced and replaced with new landscape areas.
Email interview conducted by John Hill.