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San Francisco War Memorial Veterans Building

IMETCO
imetco.com
information@imetco.com

Built in the early 1930s, the San Francisco War Memorial Veterans Building recently underwent a major structural and interior renovation – a delicate process requiring careful planning and precise attention to detail to preserve the building’s charming Beaux Arts-style architectural features. The restoration was recently recognized with one of the American Institute of Architect’s most prestigious awards – a Special Commendation for Historic Preservation.

The Veterans Building is recognized as one of the finest and most complete manifestations of Beaux Arts architecture and civic design in the United States.

The four-story, 240,000-square-foot building, located in the city’s Civic Center District, is home to the American Legion War Memorial Commission as well as the Herbst Theatre, a lavish, three-story space in the center of the building. The city’s Art Commission and the San Francisco Opera also occupy space within the building.

The facility was long overdue for a seismic upgrade. The building’s structural integrity had remained untouched since it was damaged by the Loma Prieta earthquake in 1989. A structural engineering study conducted in 1996 revealed that in the event of a major earthquake, the structure would sustain significant damage and pose serious threats to building occupants. Along with that, the building had badly deteriorated systems, comprised largely of the original 1932 equipment, including 80-year-old boilers.

The nearly $100 million renovation project began in 2010 and was completed last fall. National engineering firm, Simpson Gumpertz & Heger Inc. (SGH), served as the waterproofing consultant on the project with Carey & Co., Inc. serving as the historical preservation architectural firm. Pankow Builders served as the general contractor with Pioneer Contractors, Inc. as the installers.

“The project began as a structural upgrade, but that triggered all kinds of other necessary upgrades like electrical, mechanical, plumbing, power distribution and life safety. The list just goes on,” explained Andy Maloney, project architect with the San Francisco Department of Public Works.

As with any large, complex project involving a historic building, this one was fraught with many challenges. There were various decorative materials and ornate finishes throughout the Veterans Building – some that needed restored and others that needed repaired – meaning contractors not only had to duplicate the materials but also had to replicate the craftsmanship.

Hundreds of beautiful, one-of-a-kind chandeliers were cleaned, rewired and then reinstalled. Doors were rebuilt to match originals and custom hardware was designed in keeping with the theme. The theatre stage was modernized with a new rigging system, sound system, pit lift and widened stage.

Along with the aesthetics, a fixed-base concrete shear wall scheme was installed to improve the structural integrity of the building, which is now expected to fare even better in a Loma Prieta-scale earthquake than it did in 1989.

Work was also completed on the exterior of the building, including replacing the original lead-coated-copper, board-and-batten-style roof. That may have been the project’s most complicated challenge.

The more than 80-year-old roof was originally handcrafted with two-inch tall battens installed two feet on center with lead-coated copper laid between them. They were done in 10-foot lengths with crosswise laps.

Since lead-coated copper isn’t readily available today, and it is prohibited to knowingly utilize lead in the storm drain system in California per Proposition 65, additional materials were explored for the replacement of the roof, including zinc-coated copper, stainless steel and domestically sourced zinc and titanium.

After reviewing the characteristics of each material, it was determined that zinc would satisfy the project’s objectives: providing long-term, low-maintenance watertight protection while maintaining the building’s original aesthetics and original color. Zinc is a self-healing and self-cleaning metal that requires no maintenance other than keeping gutters clean to allow for proper drainage. The expected life cycle of zinc is anywhere from 80 to 100 years.

To mimic the original look as closely as possible, engineers at IMETCO, a premier metal product manufacturer based in Norcross, Georgia, designed and manufactured a custom, 24-inch wide, 1 mm zinc panel with a custom extrusion and profile.

The completely customized solution passed standard ASTM 1592 testing for structural performance. Additional ASTM 1646 Water Penetration and ASTM 1680 Rate of Air Leakage tests were performed to guarantee a watertight installation.

Next up was installation. Like most metal roofs, zinc requires proper ventilation. The panel system is suspended from clips, creating a gap that allows air to move through and underneath the panel and out at the top of the ornate cornice details as well as at the base of the skylight. The glacier gray Series 300® symmetrical standing seam zinc panels were installed full length. Scaffolding and netting was installed around the entire building as a safety precaution.

With skylights covering a large portion of the roof, the challenge intensified. The skylights were directly flush with the panel system with the glazing traveling through the batten system. Normally, skylights are installed on top of the seam, allowing for the perimeter to be more easily waterproofed. The local IMETCO representative spent four months working on a ground level mock-up with the roofer’s superintendent and foreman to produce the final details for the skylight flashing that would satisfy the requirements of the Veteran’s review committee and the San Francisco Historical Society.

“The installation of the skylights took a lot of field coordination with the detail. There was a lot of custom fabrication and soldering that had to be done to integrate the skylights into the roof as they had been originally,” explained George Jones, director of field services at IMETCO.

He continued, “We built five or six mock-ups with consulting engineers and installers to continue refining the complex details. It was a matter of creating custom details to mimic the historic look and then customizing those custom details.”

The meticulous detailing was critical in ensuring the watertight integrity of the skylights.

The restoration of the Veterans Building marks the eighth public building in the Civic Center District to be restored since the 1989 earthquake, a cumulative investment of more than $1 billion.

Finished project photos 1-3 by Henley Photography 
Before pic and mockup photo by The Garland Company

About IMETCO

IMETCO_logoIMETCO manufactures metal products for the building envelope, including metal roofing, metal wall, and metal deck systems and accessories. For more information, visit  www.imetco.com.

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