The Brower Center at Oxford and Allston Streets.

The recently completed David Brower Center in downtown Berkeley is a memorial to a major figure in this country’s environmental movement. Brower served as the first Executive Director of the Sierra Club from 1952 fo 1960 and later founded such environmental organizations as Friends of the Earth, the League of Conservation Voters, and Earth Island Institute. He inspired a generation of environmental activists, some of whom now work in the building at the intersection of Allston Way and Oxford Street that bears his name.

Thirty some national and international groups occupy 24,000 sq. ft. of office space on the building’s upper three floors. Their mission is to foster collaborations, engage new people in advocacy and facilitate cross-sector communication and partnerships.

Although the work of the building’s tenants is a story in itself, the subject of this article is the Center’s building design and its structural system, which were created to insure that the physical embodiment of Brower’s legacy would be a state-of-the-art expression of his life’s work. The building is on track to receive a LEED platinum rating—the highest possible—from the US Green Building Council.

Plans show the shape of the site and the Brower Center's rounded facade derived from the street corner it faces. Plans of the Oxford Plaza housing are shown on the right.

The building’s site is unusual in that the corner it faces has a rounded edge. This feature prompted the architects, WRT/Solomon E.T.C., to design a rounded façade that enables a more natural flow of space than the typical right-angled street corner. Pedestrian traffic flows from the building’s entrance on Allston Street past the Center’s ground-floor restaurant, Gather, to a gated open space between the Center and the apartment complex, Oxford Plaza.

The building’s façade suggests a temple form with engaged columns set on a raised base, a slightly projecting attic story above, and a cornice, which departs from the classical type by continuing the solid array of photovoltaic panels on the south side with a slatted trellis that follows the roof line and rises as it curves around the eave from south to north like an upturned hat brim.

View of the Brower Center from a building across Oxford Street.
Both photographs on this page are by Tim Griffith.

The panels’ downward slant on the south side moderates the greater amount of daylight entering the building from that direction and reduce heat gain in the summer; their upward tilt on the north side increase the admission of light to meet the seasonal greater need. Measures like these have made the interior nearly 100% daylit.

In respect to materials, the metal used for the façade is zinc, which requires less energy to mine and work into forms than aluminum or steel. Its matt surface avoids glare. The window glass redirects sunlight and thereby reduces heat gain. Operable window sections allow changes in ventilation.

The concrete used in the building is 70% blast furnace slag in the foundation and 50% slag in the super structure. The use of this by-product of manufacturing steel reduces the building’s energy content and its “carbon footprint” by 40%. The Brower Center is the first Bay Area Project to use high-slag concrete on such a scale.

The Roman Catholic Diocese of Oakland, established in 1962, was strongly influenced by the 1962-1965 Second Vatican Council. Subsequently, the diocese took the name of its new cathedral, Christ the light, from the council document, Lumen Gentium (Light of All People.) The inclusion of the word, light, in the name inspired the architects at the San Francisco office of SOM to design the cathdral as the embodiment of light. Thus, the building now nearing completion on the west shore of Lake Merritt is wrapped in translucent walls that convey the impression of layered light.

Night photograph of the model from SOM In 2003, the design and construction process of the cathedral complex began on its 2.53-acre site. To provide maximum daylight year-round, the building was oriented southeast/northwest. The entrance faces Lake Merritt at the end of a walkway rising from the intersection of Harrison and 21st Streets. Inside the entrance, the baptismal font reminds visitors that baptism is the rite of entry to church membership. Seating for 1500 people is arranged in a semi-circular plan centered on the altar at the church’s north end. Space for the choir and an organ is located behind the altar along with a Eucharist chapel for eighty people. The chapel is separated from the sanctuary by a curved wall of wood blocks. A crypt is located on the floor beneath the altar, a common arrangement in many important churches around the world. Light is drawn down to the crypt through openings in the floor around the altar.

Graphic image from SOM The building’s plan is based on an elliptical shape formed by the overlapping intersection of two circles. (This shape, also called a mandorla, is most commonly used in Christian symbolism to frame the figure of Christ.) The interior, shaped vertically by the tilted-up sides of the ellipse, is enclosed by a wall composed of two structural layers. The convex inner layer is divided by curved glue-laminated wooden ribs into segments filled with laminated wood slats. As the wall rises, the space between the slats widens to increase the amount of daylight entering the building. The change of the slats’ angle relative to the floor also allows more views of the outside while reducing direct solar heat gain to the lower zone occupied by the congregation. This louvered layer ends approximately fifteen feet above the floor. The outermost layer is a curtain wall made of an aluminum and glass grid that protects the wooden layers from the weather. The curtain wall’s aluminum mullions continue above the roof to create a crown of finials The width of the space between the wall’s two layers decreases from twelve feet at their base to three feet at the top. The layers are interconnected by continuous tension members of galvanized steel rods and discontinuous compression members of tapered wood struts. This so-called tensegrity system, famously used by Buckminster Fuller in his spherical structures, enables each member to operate with maximum efficiency and economy