AMERICAN ENTERPRISE GROUP, NATIONAL HEADQUARTERS RENOVATION, Des Moines, Iowa | 2015

Architects: BNIM

Original Architects: Gordon Bunshaft, Skidmore, Owings & Merrill (1965)
Client: American Enterprise Group

The American Enterprise Group (AEG) national headquarters is an eight-story office building in downtown Des Moines, Iowa. The venerable building, designed by SOM’s Gordon Bunshaft, was completed in 1965.

The project is being considered for the National Register of Historic Places; improvements were made utilizing historic documents and the Secretary of the Interior’s Standards for Rehabilitating Historic Buildings.

The innovative rehabilitation reinforces the original design intent as follows:

This in an invisible rehabilitation. The 1966 LIFE magazine article stated the building had “No Fat.” The building’s original systems were meticulously integrated with the building architecture. The work required substantial demolition of walls and finishes which were obsessively and elegantly reconstructed to accommodate new systems, including the important addition of life-safety.

The original building meshed together workplace and AEG’s significant art collection -- a museum within an office. The renovated space addresses human efficiency and evolving workplace standards with systems that enhance human productivity while making the art an integrated part of the experience.

This exposed cast-in-place and precast concrete building included many groundbreaking characteristics: an integrated mechanical system; indirect lighting; minimal windows on the east and west facades; north and south facades with expanses of glass; and substantial overhangs to maximize daylight and minimize heat gain.

These concepts were preserved and augmented with energy efficient systems.

On Levels 3 through 8, a custom thermally broken insulated glazing system was installed to match the profile, finish and tint of the original building. The Entrance and Second Levels remains and frames with panels of annealed clear glass as large as nine feet by eighteen feet.

Architects: BNIM

Original Architects: Gordon Bunshaft, Skidmore, Owings & Merrill (1965)
Client: American Enterprise Group
General Contractor: Ryan Companies US, Inc. 

Structural Engineers: Charles Saul Engineering
MEP Engineers: Design Engineers
Photographers: Nick Merrick/Hedrich Blessing, Ezra Stoller