WINNER: Los Angeles City Hall, Los Angeles, CAWhen the Los Angeles City Hall was completed in the late 1920s, Mayor George E. Cryer promised the city that the building would honor the stateliness of America’s most rapidly growing city.Since its dedication, the building has been featured in movies and television – it appeared in 1953’s “War of the Worlds;” served as police headquarters for 10 seasons of “Dragnet;” and appeared in episodes of “Matlock,” “LA Law,” and “Hill Street Blues.”When the decision was made in 1993 to modernize City Hall, both the architect (Los Angeles-based AC Martin Partners) and the construction company (Bethesda, MD-based Clark Construction) were committed to Los Angeles’ initial goal of not altering the historical monument’s appearance. “It’s an extremely well-known building, so there’s a high degree of sensitivity by the public to altering the appearance of the building,” explains Christopher Martin, CEO, AC Martin Partners Inc. “[The tenants] didn’t want to change anything historically. They wanted to keep the building the way it was and bring it up to present-day code.”For Martin, this was one of the most important projects of his career. His grandfather, AC Martin, was one of the original architects of the Los Angeles City Hall. “He was the architectural engineer, so it was his original structural design. This was really the upgrade of it,” explains Martin. “It’s one of the most important projects of his career, and to come in and do the complete $300 million renovation makes it one of the most important projects of my career.”Not long after the design of the project had begun and a budget had been established, the Northridge earthquake shook southern California in January 1994. The damage to Los Angeles City Hall was so great that it could no longer maintain occupancy. The building was vacated and tenants were relocated. The budget and design had been based on completing the modernization while the building was occupied. After the earthquake, budgets and designs had to be re-evaluated. “It was a monumental task,” Martin says.Because of the earthquake, project costs grew much higher than initially planned. The Federal Emergency Management Agency (FEMA) was able to supply almost 50 percent of the project’s cost due to the natural disaster.Project Restore, a Los Angeles-based non-profit organization, was another key organization that was able to raise funds for the modernization of the facility. Seismic ShelterThe tallest building in the world to ever receive a seismic upgrade, the Los Angeles City Hall now has 526 isolators to strengthen the core of the building. In the event of another earthquake, the building will remain stable and in one spot while the ground will move underneath. Dampeners were also installed to reduce the motion of the building, acting as “big shock absorbers absorbing the energy created by a seismic event,” explains Jim McLamb, project executive, Clark Construction. “We physically jacked the building up off of its foundations, column by column, to insert the isolators. It was all done underneath the building. We did everything in an excavated area with very limited access.” Facilities utilizing these types of materials are subjected to only one-third to one-fifth of the horizontal acceleration of traditional structures during a seismic event. An additional 3,000 tons of structural steel and shear walls were also added, making the building more rigid and less likely to sustain damage. This combination of technologies maximizes Los Angeles City Hall’s likelihood of withstanding future earthquakes.Protecting and Preserving“Technically, the most difficult challenge was to try and upgrade the seismic capacity of the building without damaging the historical spaces,” describes Martin. Because of its role and recognition, historic preservation played an important role in the modernization of the building. California’s State Historical Preservation Office (SHIPO) assisted in identifying which elements had to be maintained. “A lot of historic elements included the detailed and ornate murals that line and ordain the ceiling of the third floor corridors,” says McLamb. “Other parts included historic light fixtures. These are not your typical production-type, off-the-shelf fixtures – these are cast-iron, cast-metal fixtures. It was a renovation [of] materials and fabric that are pushing 80-some years old.”Light fixtures were cataloged and photographed, removed from their settings, cleaned, and rewired to meet current energy codes. Those that couldn’t be salvaged were replicated and recreated to maintain the flavor of the initial construction. “The process may sound pretty standard and easy, but that took almost 21/2 years to complete. It took an incredible amount of time, planning, and effort,” emphasizes McLamb.Paint chips were analyzed to determine the original composition of the first coat of paint used in 1928. After the original color scheme was determined, it was used to restore murals and ceilings throughout the hallways. McLamb describes the process: “There’s canvas that the murals were painted on to. The murals were not painted directly onto the ceilings.”An original elevator cab, not used in City Hall since the ’40s, was found and used to replicate and design new elevator cabs throughout the building. “We took out the funny ones that were made in 1970 and replaced them with replicates of the original 1920 elevators cabs. We tried everything to bring the building, in appearance, to the historical period in which it was built. We were very successful with it,” states Martin.Enhancing Existing SystemsUpgrading and improving current systems was also a major part of the project. Fire and life safety precautions, ADA compliance, and mechanical and electrical systems were all updated. Exterior fire escapes were removed and modern-day fire escapes were added, and the building was redesigned to accommodate air-conditioning. “A little air-conditioning has improved the mood in City Hall,” says Ronald Deaton, chief legislative analyst, City of Los Angeles.While that job in and of itself sounds difficult, all the necessary upgrading and construction had to be done while maintaining the building’s electrical system. Because the Los Angeles City Hall is home to the city’s 911 emergency receiving center, this vital service had to remain active 24 hours a day throughout the project. “It was sitting down, making sure that the subcontractors [were] educated about the system,” says McLamb. The 911 system ran down the entire height of the 28-story building, through the basement, and underneath the street – and it was imperative that the system remained untouched.Scout teams were used to scope out the existing mechanical system. “We had a group of about five people, and that’s all they did. They walked the existing systems and structure, scouted the building out, and came back and coordinated the mechanical and electrical systems. There was a cost upfront for this extra time and commitment, but it paid dividends when it came to putting the systems in place,” says McLamb. The team searched for places for new electrical lines, new ductwork and plumbing, and reported on how difficult the concrete was going to be to work with.The newly-revamped Los Angeles City Hall has been a hit with tenants. “It was a honeymoon,” describes Martin, “and it still exists today. The people just love the building.”“The response to all the modernization has been overwhelmingly positive – especially the installation of HVAC, fixing the elevators, and improving the electrical system to support modern technology. City Hall business is flowing and no one misses the old radiators,” says City of Los Angeles’ Deaton. “Three days a week, Council members, their staffs, and visitors (sometimes totaling hundreds) come together to deliberate in a room filled with history, but using technology fit for a corporate boardroom – ornately carved wooden desks with imbedded touchscreen monitors, flat panel screens incorporated into historic ceramic walls, modern A/V equipment tucked neatly behind marble columns and under marble floors – all of these are examples of the meshing of new and old. City staff and contractors worked very hard to respect the traditions of this building in their redesign, and I think they did an outstanding job.”Clark Construction’s McLamb explains that sometimes when tenants are evacuated from a building and moved to different places due to a renovation, one fear is that people won’t want to come back to the original building – especially if it was an unpleasant place to work. “Everyone just scrambled to get back there,” he says. “It’s a gorgeous facility. The systems function the way they should; the design works the way it was intended. The other aspects of bringing it up-to-code ADA-wise, elevator-wise … it all came together as planned.”Leah B. Garris ([email protected]) is editorial coordinator at Buildings magazine.