Upon its completion in 1918, the building that is now the Atascadero (Calif.) City Hall was the very picture of stability. Intended as the centerpiece of Atascadero Colony—a planned utopian community—the Italian Renaissance structure featured a cruciform plan, with ornate central rotundas on the first and fourth floors.
Though the idealized colony never really jelled, the area did thrive, and the building passed through several commercial uses before the County of San Luis Obispo acquired it in 1950. When the city of Atascadero was incorporated 29 years later, the county handed the building over for city offices. The hall, with its grand pillared entrances and red-tiled dome, is featured on the city seal and listed on both the National and California Registers of Historic Places.
In December 2003, the 6.5 magnitude San Simeon earthquake ravaged Atascadero. As city workers dove for cover, the upper rotunda was twisted and wrenched away from its structural moorings. Interior walls and exterior masonry were extensively damaged, and the building was ultimately red-tagged. However, city officials were determined to restore, and improve, the beloved landmark.
Pfeiffer Partners Architects undertook a two-year assessment, including a laser-scan analysis as well as painstaking physical investigations and measurements. The Atascadero Historical Society, an enthusiastic collaborator, provided invaluable documentation of original conditions. Three packages of work were eventually developed: demolition, FEMA-funded damage repair and hazard mitigation, and city-funded rehabilitation.
PLATINUM AWARD
ATASCADERO CITY HALL
Atascadero, Calif.Building Team
Submitting firm: Bernards (construction manager)
Owner: City of Atascadero
Architect: Pfeiffer Partners Architects
Structural engineer: Nabih Youssef Associates
MEP engineer: Davidovich & Associates
General contractor: Diani Building Corp.General Information
Size: 58,900 sf
Construction cost: $21.7 million
Construction time: June 2010 to September 2013
Delivery method: CM agency/multi-prime
The 2008 economic crash posed financial difficulties, and anticipated state funding was eliminated in the subsequent recession. Meanwhile, water infiltration caused additional damage despite the owner’s best efforts to keep rain out. Under the management of Bernards, construction finally began in 2010, nearly seven years after the quake occurred.
Stabilizing the structure was obviously the most pressing need. The original building consisted of cast-in-place reinforced concrete floors and unreinforced masonry infill walls between a structural steel, concrete-encased post-and-beam skeleton. Above the fourth floor, the building was essentially an unreinforced masonry structure.
Crews strengthened the existing foundation by drilling 248 micro-piles 80 feet deep into bedrock, and pouring pile caps below the foundation. A new structural concrete slab-on-grade was installed at the basement level. Interior perimeter walls up to the fourth floor were stripped to reveal the structure, which was reinforced with more than a million tons of shotcrete and 80,000 pounds of rebar—in essence, creating a building within a building.
To fix the upper floors and dome, crews removed most of the exterior cladding, then rebuilt with additional steel and fiber-reinforced polymer instead of shotcrete, which would have been too heavy. Existing steel was horizontally and vertically braced, and roof dome framing members were retrofitted.
When structural improvements were complete, crews used as much of the original masonry as possible to rebuild the walls and roof. In the heavily damaged upper section, about 15% of the roof tiles and 80% of the bricks had to be replaced with color-matched materials. When possible, original tiles, fascia balustrades, and decorative plaster were repaired, cleaned, and returned to their original spots.
The lower rotunda benefited from a new paint scheme inspired by the greens and browns of the California landscape; the painter, a local artisan, donated half of his change-order hours back to the city. Second-floor window overlooks, once blocked, were uncovered and restored, providing views into the space from surrounding office zones. Light boxes behind frosted lunettes give the illusion of natural daylight. In reality, this dome is internal and is topped by a second rotunda housing the City Council chambers.
IMPROVING INTERIOR DESIGN
Interior reconfiguration was also crucial to improving functionality. Over the years, alterations had resulted in a confusing layout and awkwardly shaped spaces, as well as problematic ventilation. Crews removed most of the interior partitions and built new walls to establish a more sensible floor plan. Efficient HVAC and communications infrastructure was installed.
The lower rotunda was programmed as lobby space and a permit center. Three floors of offices surround this focal point. City Council chambers were constructed in the domed upper rotunda, which once held a library. A small historical museum received a place of honor, reinforcing the building’s link with the town.
More than 90% of construction dollars went to firms on the Central Coast, including $5.5 million to local glass, concrete, and masonry contractors. The final construction cost was $3.3 million less than the original $25 million estimate. Bernards credits the multi-prime contract process, encompassing 17 separately bid categories, for the savings. City Hall opened on schedule in August 2013, just in time for Atascadero’s centennial—an embodiment of civic resilience, determination, and pride.
Elegant detailing, a hallmark of the Italian Renaissance style, was re-established in the post-earthquake reconstruction.
Related Stories
| Jan 30, 2012
Hollister Construction Services to renovate 30 Montgomery Street in Jersey City, N.J.
Owner Onyx Equities hires firm to oversee comprehensive upgrades of office building.
| Jan 27, 2012
Caterpillar reports record sales and profit for 4Q and full-year 2011
Momentum carries into 2012 with sales and revenues outlook raised to $68 to $72 billion.
| Jan 27, 2012
Smith Seckman Reid opens two new offices
Smith Seckman Reid, Inc. (SSR), an engineering design and facility consulting firm, has opened two new offices, one in Chicago, the other in Washington, D.C.
| Jan 27, 2012
BRB Architects designs new campus center for Molloy College
Intended to be the centerpiece of the College’s transformation from a commuter college to a 24-hour learning community, the “Public Square” will support student life with spaces such as a café, lounges, study rooms, student club space, a bookstore and an art gallery.
| Jan 27, 2012
Columbia University’s New Core Laboratory aims for LEED Silver
Construction manager Sordoni Construction Co. along with the design team of Payette Architects and Vanderweil Engineers will provide design and construction services to renovate the majority of the existing Core Lab building to create the new Lamont Center for Bio-Geochemistry.
| Jan 26, 2012
Three dead, 16 missing in Rio buildings collapse
The buildings, one 20 floors high, collapsed on Wednesday night in a cloud of dust and smoke just one block away from the city's historic Municipal Theater.
| Jan 26, 2012
Siemens launches smoke detection knowledge center
New knowledge center web site demonstrates efficacy of smoke detection.
| Jan 26, 2012
Hendrick Construction completes Osso Restaurant in Charlotte
Designed by François Fossard, Osso's upscale interior includes tapered, twisted decorative columns and an elegant fireplace in the center of the lounge.
| Jan 26, 2012
HOK partners with USGBC on design of Haiti children's center
Passive design principles give form to a sustainable, restorative environment for the children of Haiti.
| Jan 26, 2012
American Standard names Gould as president and CEO
Gould succeeds Don Devine, who led the successful turnaround of American Standard Brands.