Architect: Ware Malcomb, Los Angeles, CA
Engineer: Cary Kopczynski & Company, Bellevue, WA
General Contractor: J.H. Snyder Construction Inc., Los Angeles, CA
Concrete Contractor: Bomel Construction Company Inc., Anaheim Hills, CA
Reinforcing Bar Fabricator: Harris Rebar
Total Project Size: 244,000 sq ft (office) 210,000 sq ft (parking garage)
Award: 2016 CRSI Award Winner – Commercial Building Category
Photography: Cary Kopczynski & Company, Bellevue, WA
Located in Hollywood’s Media District, Hollywood 959 is a premier creative office campus targeted toward the media and entertainment industry. It consists of two uniquely shaped office buildings (East Wing and West Wing) that house offices for production, post-production and editing. The East Wing is four stories, and the West Wing is five stories with a two-story “Creative Wing” (topped with a barrel roof with exposed steel bow trusses on the interior), evoking the atmosphere of an industrial loft space. Hollywood 959 was designed to cater specifically to the creative office market by incorporating the latest developments in modern workplace design. To that end, the structural design incorporated large floor plates with minimum columns (and other structural obstructions), as well as exaggerated ceiling heights. This allowed for multiple office configurations and sizing, including the opportunity for exterior circulation along the window line to create a central work environment.
The eight level parking structure (700+ parking stalls) was designed to be free of internal columns and walls to maximize openness and create a sense of security. Additionally, structural design and construction used “techniquest” to maximize durability so that deterioration from water and weather is minimized.
Several sustainable features are woven into the design of Hollywood 959, which qualifies for LEED® Silver Certification from the United States Green Building Council. Operable windows and an outdoor air monitoring system enhance the workplace environment by providing occupants with fresh air and natural ventilation, while lighting level controls reduce energy consumption. Full-height glazing is utilized throughout to maximize opportunities for daylight, while providing views of the outdoor environment to ninety percent of the building occupants.
In utilizing a highly efficient cast-in-place (CIP) reinforced concrete structural system, thinner slabs and shallower beams reduced the overall building mass. Since seismic loads are linearly correlated to mass, this resulted in lower seismic loads, smaller shear walls and smaller foundations. Additionally, the effective use of high-performance concrete and high-strength reinforcing steel (rebar) minimized material quantities, which reduced the input energy and carbon footprint of the structure.
STRUCTURAL FRAMING SYSTEM
The two uniquely shaped office buildings have their respected cores located in the wings of each building. Due to the Los Angeles area’s high seismicity, balancing the lateral irregularity to meet demanding seismic requirements required significant effort and careful attention to detail. The diaphragm design between the various lateral resisting elements had to be carefully considered to ensure that a safe and efficient load path was provided. As the project began construction, it was determined that underground utilities had to be relocated and several spread footings had to be shifted or stepped to accommodate the new utility lines.
The floor system in the office buildings were optimized so that there were no exterior beams in order to achieve the owner’s goal of large window area and air circulation. A CIP-reinforced concrete beam/slab system was used for most of the floor area, allowing for large 40’x30’ bays. In select locations, two-way flat plate concrete slabs were utilized to maximize ceiling height and create a flat soffit at exposed areas. The East office building featured a large barrel vault roof with exposed trusses supported by an exposed concrete beam system.
The parking structure used a CIP reinforced concrete beam/slab floor system, which allowed for long spans of greater than 60 feet. This framing system maximized the parking area and minimized material usage. A reinforced concrete moment frame system was located at the perimeter of the structure, sized such that the beams would also function as a vehicle barrier, further reducing the structural cost. An elevator core was located at one edge of the structure and isolated with a seismic joint, preserving the concentric seismic behavior of the moment frames used in the garage.
REASONS FOR CHOOSING REINFORCED CONCRETE
Hollywood 959 brings a unique feature to the greater Los Angeles office market – a concrete structural frame. While most similar developments have chosen structural steel, the Hollywood 959 design team converted the office buildings, which were initially designed for structural steel, to CIP concrete because of its design flexibility, construction economy and local availability. The need to create long, column free floor spans and work spaces with excellent acoustical properties led the design team to choose reinforced concrete for both of the Hollywood 959 office structures (East and West Wing). Concrete shear walls resist seismic and wind loads, and a wide-shallow beam system was used to reduce the number of interior columns and maximize office space flexibility. Two-way flat post-tensioned slabs were used in some areas to eliminate beams and maximize floor-to-ceiling height.
Through the use of reinforced concrete and a wide-shallow “ribbon” beam system, the structural engineer created large, flexible floor plates with 40 feet spans that allow for multiple office plan arrangements and sizing, including the opportunity for exterior circulation along the window line. Additionally, the use of CIP concrete created a soffit height of 12’-4” while maintaining a floor-to-floor height of 13 feet.
The eight-level parking structure was also constructed of cast-in-place reinforced concrete, using post-tensioned slabs and beams. Special “Perimeter” reinforced concrete moment frames were constructed to resist seismic and wind loads equated with the area. A long-span beam system was used to minimize columns and provide maximum openness. Because of the use of perimeter moment frame beams, the need for a separate vehicle barrier system was eliminated.