Award of Merit: Longevity Category
Evans Hall Restoration—12 Years Later
Submitted by Sika Corporation
University of California, Berkeley
San Francisco, CA
San Rafael, CA
Evans Hall is a 10-story building that houses the depart- ments of statistics, economics, and mathematics at the University of California, Berkeley. The building was constructed in 1971 and contains 26 classrooms, multiple computer labs, common rooms, the Mathematics Library, department offices, and a large computer lab.
In 1999, after almost 30 years in use with little maintenance done, safety concerns were raised as a result of pieces of concrete falling from the building’s façade. Poor initial concrete placement with minimal coverage of reinforcing steel, combined with exposure to CO2 and moist salty air from nearby San Francisco Bay, led to rapidly accelerated corrosion of the building’s reinforcing bars. Because the building sits on a major seismic fault line, the repairs were needed to maintain the structural integrity of the building.
The initial work on the building was divided into two phases. In Phase I, hundreds of spall repairs were made to the structure; then, the entire building was re-leveled with polymer-modified mortar with a spray-applied method. Phase II consisted of applying a high-performance, anti-carbonation, crack-bridging, elastomeric wall-coating system for waterproofing and corrosion protection, as well as a much-needed aesthetic upgrade.
Twelve years later, all of the spall repairs are performing well and there are no signs of new spalls occurring. Evans Hall is expected to last another 41 or more years without major repair or restoration. There are no signs of cracks or rust stains on the building, and the custom colors chosen show no signs of deterioration. This coating system seems to have made a significant impact on the building’s ability to stay watertight and resist corrosion, which should prevent new corrosion from occurring.