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F.W. Dodge California Construction Link Institutional Construction Feb.99
San Francisco City Hall’s Seismic Salvation The $293 million restoration reaches the punch-list phase
By Bill Davis
The rescue of San Francisco’s City Hall is the kind of project that every construction manager looks for - new, different, complicated - a signature job for a successful career, according to Bill Sexauer, senior project manager for Huber, Hunt, Nichols, Inc., of Indianapolis.
The $293 million restoration is now winding down with the first and second floors occupied. The third and fourth floors, along with the basement, are in the punch list stage, according to Sexauer.
It started as a $103 million FEMA seismic repair job inspired by 15 seconds of terror called the Loma Prieta earthquake, October 17, 1989. In the aftermath of that disaster City Hall was one of the more than 20,000 buildings damaged. The 302-ft. tall dome on City Hall twisted on its steel frame like a cap on a bottle, moving several inches. Cracks developed on every floor, plaster fell from the walls. While the building was never in danger of falling down, engineers determined its seismic resistance had to be improved or any repairs made would be wasted in the next big quake.
Voters passed a $332.4 million bond issue in January, 1990, for repair on 191 city buildings including City Hall. Designers started working in 1991 on the project. The designs were completed in 1994 and the improvements called for additional funds. By the November 1995 elections, the project was augmented by a city bond issue passed, to turn it into a full-scale restoration.
At its heart, the unique nature of this job is the blend of modern technology combined with rigorously authentic restoration techniques. On the modern technology side, the two block-long building was cut from its foundation and now “floats” on 530 isolators - shock absorbers designed to dissipate earthquake motion and allow the building to sway, horizontally, up to 26-inches without shaking apart. These isolators are essentially big rubber bearings, 37-inches in diameter, according to Konrad Erickson, vice president of manufacturing for DIS, Inc., Lafayette, and the manufacturer of the material. DIS also supplied isolators for Oakland’s City Hall renovation project.
Sheedy Drayage Co., Inc., of San Francisco was the subcontractor who installed the isolators, first by jacking up the supporting columns of the building one at a time, then cutting those columns and positioning the isolators under them, then restoring the weight to the structural member.
The technology side also transformed the 83year-old building into what some are calling the “smartest” building in the state, fully wired for Internet access and television broadcast, and equipped with “touch screen” technology allowing city and county officials an up-to-date way to cast their votes and do research.
The high-tech communications equipment system was designed by Kenneth Fause, of Smith, Fause & McDonald of San Francisco, for Ceitronics, of San Jose, the prime electronics contractor on the project. The effort called for 66 different product manufacturers whose equipment had to fit within the restrictions of the historical restoration.
On the restoration side, the City Hall dome has been trimmed with $400,000 in gold leaf, allowing the citizens of San Francisco to see the original glory of its civic palace which houses both city and county offices. The original dome gold washed off, leaving exposed copper sheathing beneath, so most citizens only recognized the green patina of oxidized copper as the rightful color of the dome.
That dome has now been reinforced with 1,200 tons of steel to prevent a repeat of the four inch “corkscrew” twist it received in the 1989 quake, according to Sexauer.
The retrofit project also included the careful removal and cleaning of some 30,000 pieces of marble from the building’s walls and floors. The most startling changes are the building’s first floor light courts, areas unseen by the general public since the 1950s. These light courts were shut off by poured concrete floors that were needed to house more city worker desks. With the concrete removed, these huge (60 feet by 120 feet) sky-lit spaces are available for receptions or exhibits.
The skylights that illuminate these areas were rebuilt by Architectural Skylight Company, Inc., of Waterboro, ME, who supplied the materials and did the installation, according to Francis O’Neill, vice president of sales and marketing. Architectural Skylight had been involved with Huber, Hunt, and Nichols on the San Francisco Main Library project. The firm also provided skylights for the fourth floor areas of the City Hall building.
The south light court is being outfitted for exhibits as a museum of San Francisco history. A high-tech innovation will end an age-old complaint that audience members couldn’t see the charts and drawings being shown to the commission. A newly installed electronic device called Wolf Vision will enable audiences as well as officials seated behind the rostrum to view the graph or a drawing at the same time.
City Hall now is expected to house about 1,000 employees, about 300 less than it contained in 1995. Clark Manus, principal architect of the team that designed the renovation, said that then many workers were “shoehorned” into space in the old City Hall. These workers are now being accommodated in other buildings throughout the city. Manus was principal architect of a joint venture team that includes Finger & Moy, Komorous-Towey and Elsessor & Forell Engineers, all under the direction of Tony Irons, project manager for the city.
“This is a great, historic building,” Manus said. “This process has brought it back to its original glory.”
There was a high level of detail to the restoration project. Chandeliers with lead crystal that had to be recast in southwest France because such work is no longer done in this country; new chandeliers that conceal fluorescent lights and are operated by motion detectors. Other items include three “bird cage” style elevators have been restored to public use, re-gilded and outfitted with high-speed cabs.
Other items of note include two stairways added between the basement and first floor; a surrounding concrete moat, part of the seismic reinforcement project and accessibility ramps for handicapped persons on the second floor.
Architects worked from copies of the original blueprints to get the details correct. These originals were drawn on linen and stored in U.C. Berkeley’s Bancroft Library. The original City Hall designer was Arthur Brown Jr. who also graced San Francisco with the Coit Tower and the War Memorial buildings.
San Francisco City Hall’s Seismic Salvation The $293 million restoration reaches the punch-list phase
By Bill Davis
The rescue of San Francisco’s City Hall is the kind of project that every construction manager looks for - new, different, complicated - a signature job for a successful career, according to Bill Sexauer, senior project manager for Huber, Hunt, Nichols, Inc., of Indianapolis.
The $293 million restoration is now winding down with the first and second floors occupied. The third and fourth floors, along with the basement, are in the punch list stage, according to Sexauer.
It started as a $103 million FEMA seismic repair job inspired by 15 seconds of terror called the Loma Prieta earthquake, October 17, 1989. In the aftermath of that disaster City Hall was one of the more than 20,000 buildings damaged. The 302-ft. tall dome on City Hall twisted on its steel frame like a cap on a bottle, moving several inches. Cracks developed on every floor, plaster fell from the walls. While the building was never in danger of falling down, engineers determined its seismic resistance had to be improved or any repairs made would be wasted in the next big quake.
Voters passed a $332.4 million bond issue in January, 1990, for repair on 191 city buildings including City Hall. Designers started working in 1991 on the project. The designs were completed in 1994 and the improvements called for additional funds. By the November 1995 elections, the project was augmented by a city bond issue passed, to turn it into a full-scale restoration.
At its heart, the unique nature of this job is the blend of modern technology combined with rigorously authentic restoration techniques. On the modern technology side, the two block-long building was cut from its foundation and now “floats” on 530 isolators - shock absorbers designed to dissipate earthquake motion and allow the building to sway, horizontally, up to 26-inches without shaking apart. These isolators are essentially big rubber bearings, 37-inches in diameter, according to Konrad Erickson, vice president of manufacturing for DIS, Inc., Lafayette, and the manufacturer of the material. DIS also supplied isolators for Oakland’s City Hall renovation project.
Sheedy Drayage Co., Inc., of San Francisco was the subcontractor who installed the isolators, first by jacking up the supporting columns of the building one at a time, then cutting those columns and positioning the isolators under them, then restoring the weight to the structural member.
The technology side also transformed the 83year-old building into what some are calling the “smartest” building in the state, fully wired for Internet access and television broadcast, and equipped with “touch screen” technology allowing city and county officials an up-to-date way to cast their votes and do research.
The high-tech communications equipment system was designed by Kenneth Fause, of Smith, Fause & McDonald of San Francisco, for Ceitronics, of San Jose, the prime electronics contractor on the project. The effort called for 66 different product manufacturers whose equipment had to fit within the restrictions of the historical restoration.
On the restoration side, the City Hall dome has been trimmed with $400,000 in gold leaf, allowing the citizens of San Francisco to see the original glory of its civic palace which houses both city and county offices. The original dome gold washed off, leaving exposed copper sheathing beneath, so most citizens only recognized the green patina of oxidized copper as the rightful color of the dome.
That dome has now been reinforced with 1,200 tons of steel to prevent a repeat of the four inch “corkscrew” twist it received in the 1989 quake, according to Sexauer.
The retrofit project also included the careful removal and cleaning of some 30,000 pieces of marble from the building’s walls and floors. The most startling changes are the building’s first floor light courts, areas unseen by the general public since the 1950s. These light courts were shut off by poured concrete floors that were needed to house more city worker desks. With the concrete removed, these huge (60 feet by 120 feet) sky-lit spaces are available for receptions or exhibits.
The skylights that illuminate these areas were rebuilt by Architectural Skylight Company, Inc., of Waterboro, ME, who supplied the materials and did the installation, according to Francis O’Neill, vice president of sales and marketing. Architectural Skylight had been involved with Huber, Hunt, and Nichols on the San Francisco Main Library project. The firm also provided skylights for the fourth floor areas of the City Hall building.
The south light court is being outfitted for exhibits as a museum of San Francisco history. A high-tech innovation will end an age-old complaint that audience members couldn’t see the charts and drawings being shown to the commission. A newly installed electronic device called Wolf Vision will enable audiences as well as officials seated behind the rostrum to view the graph or a drawing at the same time.
City Hall now is expected to house about 1,000 employees, about 300 less than it contained in 1995. Clark Manus, principal architect of the team that designed the renovation, said that then many workers were “shoehorned” into space in the old City Hall. These workers are now being accommodated in other buildings throughout the city. Manus was principal architect of a joint venture team that includes Finger & Moy, Komorous-Towey and Elsessor & Forell Engineers, all under the direction of Tony Irons, project manager for the city.
“This is a great, historic building,” Manus said. “This process has brought it back to its original glory.”
There was a high level of detail to the restoration project. Chandeliers with lead crystal that had to be recast in southwest France because such work is no longer done in this country; new chandeliers that conceal fluorescent lights and are operated by motion detectors. Other items include three “bird cage” style elevators have been restored to public use, re-gilded and outfitted with high-speed cabs.
Other items of note include two stairways added between the basement and first floor; a surrounding concrete moat, part of the seismic reinforcement project and accessibility ramps for handicapped persons on the second floor.
Architects worked from copies of the original blueprints to get the details correct. These originals were drawn on linen and stored in U.C. Berkeley’s Bancroft Library. The original City Hall designer was Arthur Brown Jr. who also graced San Francisco with the Coit Tower and the War Memorial buildings.
Other Feature Articles
Making San Francisco’s City Hall Smarter for the New Millennium, CEE News Special Report on DATACOM, page 14 July 1999
New Communications System to Boost Public Participation, F.W. Dodge California Construction Link, Institutional Construction Feb.99
San Francisco City Hall’s Seismic Salvation The $293 million restoration reaches the punch-list phase, F.W. Dodge California Construction Link Institutional Construction Feb.99
Timeline of History of San Francisco City Hall, F.W. Dodge California Construction Link Institutional Construction, page 16 Feb.99
Retooled City Hall Is Finally Ready To Open, San Francisco Chronicle Front Page January 1, 1999
A Treasury of City Hall Trivia, San Francisco Chronicle Bay Area Focus January 1, 1999
Light Years, San Francisco Examiner Magazine Page 7 January 3, 1999
Gold-Plated City Hall, San Francisco Examiner Front Page Dec. 30, 1998
S.F. Celebrates Floating City Hall, San Jose Mercury News Page 3b January 6, 1999
Ceitronics: wiring San Francisco for the 21st Century, San Jose and Silicon Valley Business Journal Page 14 January 15, 1999
Retrofitting “City Hall’, Systems Contractor News Front page, con’t page 17 September, 1998
City Hall by the Bay, Sound & Communications Front page, con’t page 18 February 18, 1999
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