Pei added this sculpture wing to complement and complete Des Moines Art Center, designed by master architect Eliel Saarinen two decades earlier.
The architectural concrete addition is bush-hammered inside and out to expose local aggregates in highly textured walls in response to Saarinen’s rough-cut Lannon stone facades. The new 2-story building takes full advantage of its sloped site. The upper level forms the fourth wing of the original U-shaped museum, so that instead of requiring visitors to retrace their steps, circulation was reflowed into a continuous loop around an outdoor courtyard and pool. (For safety, the original 3-feet-deep pool was transformed into a shallow sheet of water). The upper sculpture gallery is illuminated by daylight that slips in softly from the edges of a great butterfly roof. Stairs lead down to a lower exhibition level that looks out to a public park through enormous butt-joined windows. The 13-feet-deep structural screen wall of this rear elevation blocks direct sun and bounces soft filtered light inside. Like the sculpture it houses, Pei’s addition is animated by contrasting solids and voids enriched by ever-changing natural light.

The Des Moines Art Center Addition was completed in September 1968, one month before Everson Museum. Both buildings received national Honor Awards from the American Institute of Architects in 1969. It was the first time the same architect received two awards in the same year for the same building type – one that Pei was just beginning to explore.
Design Team: I.M. Pei, Design Partner; Richards Mixon, Design Architect
I.M. Pei & Associates
*Des Moines Art Center was expanded again by Richard Meier in 1985. The museum is a remarkable exemplar of modern architecture newly reinterpreted in three campaigns roughly twenty years apart.