As a shining symbol of civic pride in Los Angeles County, Pasadena City Hall stood as the stately centerpiece of Pasadena's Civic Center since 1927. To the casual observer, the rectangular edifice, designed by San Francisco Classicists John Bakewell, Jr., and Arthur Brown, Jr., appeared to be aging gracefully.
However, that placid exterior masked deep cracks within two of the hall's stair towers, extensive water damage, decaying art stone exterior features, and significant seismic defects.
Consequently, seismic strengthening, an M/E/P systems and ADA upgrade, restoration of internal and external areas, and landscaping were the main program elements that the Building Team, headed by the Clark Construction Group, Costa Mesa, Calif., was charged with handling.
Recent studies showed that a future earthquake could destroy portions of the building, so the decision was made to separate the historic structure from the ground through seismic isolation. The original basement floor slab was removed, a new foundation was excavated and installed, a new basement floor transfer system was put in place, and 240 friction-pendulum isolators were installed.
“This was an extremely complicated project,” said BD+C Reconstruction Awards judge K. Nam Shiu, P.E., S.E., MISE, VP, Walker Restoration Consultants, Chicago. “Installing a base isolation system on an existing building is difficult work.”
Interior walls were replaced, the hall's plaster ceilings were restored, and new finishes were applied. All the building's marble, light fixtures, quarry tile, wood doors, and woodwork were preserved, protected, or restored.
On the exterior, historical cast stone elements were refurbished, as well as exterior plaster and copper cladding on the dome and stair towers. The grounds were spruced up with new site paving, landscaping, planters, and decomposed granite walkways.
With such attention dedicated to preserving historic elements, the design and installation of new M/E/P systems had to be carefully woven into the architecture. Systems had to be integrated above existing plaster ceilings, within wainscots, and through existing structural beams in line with specific guidelines in extremely confined spaces. The Building Team had to do a significant amount of coring through concrete and steel to run utility lines; in some cases, soffits were created to conceal M/E/P components.
The Building Team benefited from expertise lent by the City Hall Restoration Oversight Committee, a team of 13 outside professionals appointed by the Pasadena City Council to monitor this important civic project. City of Pasadena officials often attended weekly meetings with subcontractors.
Not only did the design need to be tight, but the actual construction had to be extremely well coordinated, particularly in the basement, where multiple trades had to work together in limited space. Because the basement slab was a honeycomb pattern of holes and structural openings, guardrails and hole covers had to be constantly relocated and replaced during different phases of the project. The team had to exert extreme diligence to prevent any workplace incidents.
This effort paid off. Not only was the work successfully completed two months ahead of schedule, but during more than 541,000 man-hours under difficult work conditions, the project reported zero lost time incidents—an impressive feat when compared to the Bureau of Labor Statistics' 2005 national average rate of 2.6 lost time incidents per project.
Related Stories
| Aug 4, 2014
Facebook’s prefab data center concept aims to slash construction time in half
Less than a year after opening its ultra-green, hydropowered data center facility in Luleå, Sweden, Facebook is back at it in Mother Svea with yet another novel approach to data center design.
| Aug 4, 2014
BIM Giants: Firms enhance BIM/VDC with advanced collaboration tools [2014 Giants 300 Report]
Cloud-based data sharing, rapid iterative design, and cross-discipline collaboration are among the emerging trends in the BIM/VDC field, according to BD+C's 2014 Giants 300 Report.
| Jul 15, 2014
A look into the history of modular construction
Modular construction is more than a century old, and throughout its lifespan, the methods have been readapted to meet specific needs of different eras.
| Jul 14, 2014
Meet the bamboo-tent hotel that can grow
Beijing-based design cooperative Penda designed a bamboo hotel that can easily expand vertically or horizontally.
| Jul 1, 2014
7 ways to cut waste in BIM implementation
Process mapping, split models, and streamlined coordination meetings are among the timesaving techniques AEC firms are employing to improve BIM/VDC workflows.
| Jun 25, 2014
AIA Foundation launches Regional Resilient Design Studio
The Studio is the first to be launched as part of the AIA Foundation’s National Resilience Program, which plans to open a total of five Regional Resilience Design Studios nationwide in collaboration with Architecture for Humanity, and Public Architecture.
| Jun 19, 2014
Singapore's 'Tree House' vertical gardens break Guinness World Record
The high-rise development will have a 24,638-sf vertical garden, breaking a Guinness World Record.
| Jun 18, 2014
Arup uses 3D printing to fabricate one-of-a-kind structural steel components
The firm's research shows that 3D printing has the potential to reduce costs, cut waste, and slash the carbon footprint of the construction sector.
| Jun 12, 2014
Austrian university develops 'inflatable' concrete dome method
Constructing a concrete dome is a costly process, but this may change soon. A team from the Vienna University of Technology has developed a method that allows concrete domes to form with the use of air and steel cables instead of expensive, timber supporting structures.
| May 29, 2014
Wood advocacy groups release 'lessons learned' report on tall wood buildings
The wood-industry advocacy group reThink Wood has released "Summary Report: Survey of International Tall Wood Buildings," with informatino from 10 mid-rise projects in Europe, Australia, and Canada.