Block 89 in Madison, Wisconsin, has seen impressive changes over the past decade. Situated across the street from the Cass Gilbert-designed Capitol Building, the site has been transformed over the past two decades by Urban Land Interest, which hired Chicago’s Valerio Dewalt Train Associates to masterplan the site, as well as the construction of three new mixed-use buildings, the preservation of two historic structures, and the adaptive reuse of a third. It has been one of the largest recent development’s in the city.

Now, the team behind it has focused its attention across the street on an equally impressive project nearing completion: the rehabilitation of Skidmore Owings & Merrill’s only building in town. Known as First Wisconsin Plaza when it opened in 1974 and now called the US Bank Building, the structure was designed by SOM’s Bruce Graham, the prolific architect behind Chicago’s Inland Steel Building, John Hancock Center, and Sears Tower.

Improving the baseline energy performance of the building was a primary concern, and the developers were aware that raising it to contemporary standards required significant alterations. Eager to begin renovation, and in deference to the building’s rich heritage, Urban Land Interest initially proffered a contract to SOM in an attempt to maintain design continuity.

SOM, however, was not interested in the project. The next logical choice was Valerio Dewalt Train. “Valerio Dewalt Train has done a number of our projects, including Block 89 development,” Paul Muench of Urban Land Interests said. “We are very close and have a great trust in them.”

“We took the responsibility of modifying a Graham building very seriously,” project architect Matt Dumich said. “We were conscious of all the details, and modifications were carefully considered.” This rigor is evident in the transformation of the atria. Once uncomfortable enclosures of uninsulated glass, the curtain-wall system has been completely rebuilt, now featuring flat, insulated roofs over canted glass, providing tenants and visitors with multiple rooftop terraces.

VDTA retained the building’s original architectural language, most noticeably its structural grid, so updates are felt rather than seen. For better thermal comfort and energy efficiency, mechanical systems were replaced and major portions of the building were refitted with new high-performance glass.

Despite the formal renovations and system modifications, Dumich said his firm kept to the massing of the building and its volumes: “We always tried to keep in mind what SOM would have done, had they had the technology of today.”

A version of this article appeared in AN 01_10.14.2009_MW.