A $310 million renovation designed to keep the landmark humming with civic life and history for another century

By Linda Mack

Architect Cass Gilbert’s State Capitol is Minnesota’s iconic building. So it’s not surprising that its renovation was extensive, expensive, and thorough. What is surprising is that, in an era of partisan strife and government gridlock, the political support for a renovation worthy of the building’s history endured over time, even as the work increased in scope. When the grand reopening of the 112-year-old building was celebrated in August, politicians and the public were equally delighted.

Steering the $310 million project was HGA Architects and Engineers. The Minneapolis firm was initially selected, along with a team of consultants, to do an interior renovation in 2005. That project stalled due to lack of consensus on its scope—and a space crunch in the building that had not been resolved.

When the design effort was restarted in 2012—after a master plan for the restoration was approved by the newly formed Capitol Preservation Commission (see “It Takes a State” below)—HGA and their consulting team were again tapped. For five years, they led an immense project that upgraded the 378,000-square-foot building’s aged mechanical, electrical, plumbing, and life-safety systems; restored its decaying art, stained glass, and decorative plasterwork; and ultimately touched every interior surface and every piece of exterior stone.

“Architects, engineers, contractors, and subcontractors—none of us had ever seen such a complex, high-end, and fast-moving project,” says HGA’s Ginny Lackovic, AIA, the project architect for the exterior renovation. Senior project manager Debra Young, AIA, says more than half of HGA’s 300 Minneapolis staff members did work on the capitol restoration.

The challenges were myriad, from finding experts to rebuild sagging skylights to working around occupants running the state’s business. To manage the project, HGA worked with the Preservation Commission, the Minnesota Historical Society, and other project partners to identify four zones in the building—areas ranging from a preservation zone, where the original ornate material was largely intact, to the basement and back of house, where intrusions could be more easily accommodated.

The biggest challenge was threading new mechanical systems through the masonry and clay-tile-arch structure, says HGA’s Kimberly Sandbulte, AIA, the project architect for the interior restoration. The air intakes were in the parking lot, where exhaust from running cars could be sucked in. The whole system had to be reversed, with air intake coming in from the roof. To meet building codes, stairs were added to make continuous egress paths, but that was an invasive process, says Sandbulte. The renovation included life-safety enhancements, new lighting (95 percent is now LED), accessible restrooms on every floor, window replacement, and a new roof.

And all had to be done with an eye toward the aesthetics of a building with a decorative palette worthy of a Renaissance palace. “Before, there were places where you went from 1905 to the 1970s when you stepped through a door,” says Sandbulte. “We wanted to put the whole building back to 1905.” Carpet was stripped from corridors to reveal the original mosaic tile. Darkened murals and water-damaged murals and plasterwork were restored. Skylights were uncovered and rebuilt. New leaded-glass elevator doors were designed based on Gilbert’s drawings and one grainy photo of an original design.

Sandbulte says the supreme-court chambers saw the biggest transformation. The John LaFarge murals depicting four moments in legal history were almost illegible, and the entire room was dark. Now cove lights and restored lighting stanchions brighten the room, while acoustic panels and mechanical grills make it functional. But it would take an architectural detective to see the additions.

“The greatest compliment we get is when someone asks, ‘What did you do?’” says Young.

Other highlights of the four-year project: new public spaces, including an assembly room and exhibit space in the basement, where the floor was excavated to create enough ceiling height; new caucus spaces closer to the legislative chambers; additional dining space near the Rathskeller (the capitol’s German-themed basement café); and more public seating throughout the building.

Prior to the 2012 comprehensive master plan, HGA led asset-preservation projects that attacked specific problems—foremost among them the leaking dome. “The seven-foot-thick walls were saturated with water, and extensive water infiltration was affecting the zodiac murals and interior finishes of the drum,” says Lackovic. “After we stopped the water infiltration, it took a year and a half to completely dry out the masonry. And then interior finishes had shrunk during the drying process and needed extensive repairs.”

Repairing the stone wasn’t part of that project, but while the scaffolding was up, investigators could see that there were bigger issues, including severely damaged stone.

The exterior restoration was “a real hard sell,” says Lackovic. “There’s a perception that stone is durable.” But white Georgia marble, which Gilbert chose for its gleaming purity, is sensitive to temperature swings and thus moves a lot, creating instability. Right before the January 2011 inauguration of Governor Mark Dayton, HGA recommended that the terraces be barricaded and the entries be protected from potential hazards until a comprehensive evaluation was done.

“During that first emergency investigation, we collected 12 to 15 five-gallon pails of loose stone by just lightly tapping the stone. We could pull acanthus leaves off the columns by hand,” says Lackovic. “And the damage wasn’t isolated to one feature or side of the building; it was everywhere.” One 300-pound stone fragment looming over the accessible drive was temporarily secured.

“When parts of the building were falling, that got everyone’s attention,” says Michael Bjornberg, FAIA, a project manager for HGA until 2015, when he joined Preservation Design Works.

The capitol’s 2012 Comprehensive Master Plan included a “tier three” stone restoration, which addressed life safety, water management, and preservation. The aim was to keep as much of the original stone as possible and balance repairs and replacement to maintain a unified appearance. “I think we found the right balance,” says Lackovic. “We couldn’t match every piece with graining and color, so we picked a medium-color and medium-textured stone and did a cross-cut that worked for most of the replacements.”

The project was massive. Starting with one off-site stone fabricator, the team expanded to include four additional fabricators for a total of eight masonry contractors. Canada-based Polycor supplied the white marble from the Georgia quarry that was its only source. (The building’s original contractors, Butler-Ryan, bought the Amicalola Quarry that supplied the stone. It has since closed.)

Car-size blocks were cut into slabs of varying depths at the quarry and sent to fabricators in Toronto and other locales; mini-blocks were sent to Italy and Montreal for decorative carving; and Twin City Tile and Marble handled the onsite finishing. Less than one percent of the stone supplied—nearly 4,000 pieces—was rejected.

Four master carvers worked on site for four years trying to keep up with the fabricators. “The project was driven by the cost of the scaffolding,” says Lackovic. “We had to keep it moving.”

A third part of the renovation—tearing up the stairs and terraces fronting the capitol—was not planned. The south stairs had been repaired in the 1990s, so there was an assumption that they were sound. But shifting treads led to further investigations, which found that the limestone foundations had lost bearing capacity. “The extent of decay was not anticipated,” says Lackovic. So the south and east stairs were rebuilt and the original treads reinstalled.

At long last, in December 2016, with most of the work completed, the capitol was ready for the legislature to convene in January. Was there a sense of accomplishment? “Being aware of what the building means to the state elevates everyone’s commitment—from the top to the workers on site,” says Sandbulte. “It’s a once-in-a-lifetime project.”

“A renovation this extensive and this expensive is a rarity,” says Lackovic. “There are only 50 of these buildings.”

Location: St. Paul, Minnesota
Client: State of Minnesota
Architect and engineer: HGA Architects and Engineers
Principal-in-charge: Mia Blanchett, AIA
Senior project manager: Debra Young, AIA
Construction manager: JE Dunn Construction
Size: 378,000 square feet
Cost: $309,674,000
Completion: August 2017
Photography: Paul Crosby


It took a campaign to muster political support for the uncompromised renovation of the Minnesota State Capitol. It wasn’t a campaign to elect particular candidates; it was a concerted, long-term effort to communicate the importance of a thorough approach to Minnesota’s iconic building after a century of Band-Aids. “We took legislators on tours, met one-on-one with every legislator,” says former HGA project manager Michael Bjornberg, FAIA.

Renovation discussions began as early as 1973, when a design competition called for an underground office building to alleviate space constraints in Cass Gilbert’s historic building. That idea died on the vine, and after several more unsuccessful efforts over the ensuing decades, the State of Minnesota issued a request for proposals for an interior renovation in 2005. The team led by HGA Architects and Engineers won that bid.

But the space question had not been resolved. Legislators had moved to having private offices in the 1970s, and new caucus and hearing rooms were needed; there simply wasn’t enough room for everyone. The hard-fought decision to build a new Senate Office Building in 2013 finally resolved the space issue—and created room for new public spaces in the renovated capitol.

When Governor Mark Dayton took office in January 2011, he took on several big, stalled projects, including U.S. Bank Stadium and the capitol. Other champions included the Department of Administration (the official client), Nancy Stark and Paul Mandel of the Capitol Area Architectural and Planning Board, Senator Ann Rest, and supreme court Chief Justice Russell Anderson and Justice Paul Anderson.

In 2011, a 22-member Capitol Preservation Commission chaired by the governor and including top leadership from across state government was formed to guide the renovation. Wayne Waslaski, senior director at the Department of Administration, helped oversee the project. “When I took this job 10 years ago, I knew the work would be challenging,” he says. “We looked to other states, including Utah, to see how they had succeeded, and the preservation commission was a key factor.”

Design-scoping workshops were another key to building consensus. “We broke the project down, had open workshops on various aspects of the effort, and brought that input back to the Preservation Commission,” says Waslaski.

In 2012, the scope and budget for the renovation were approved, and the 2013 legislature passed a law that authorized and funded it. And it wasn’t the only legislation. Additional laws outlined the scope of masonry restoration; the use of particular spaces; where there would be operable windows; and the numbering of rooms. All occupants had to sign off on finishes and furnishings for their space, Bjornberg adds.

“This gift was handed down to us by past generations,” says Waslaski. “It’s our responsibility to be good stewards. The Preservation Commission maintained that position throughout the project.”

That commitment to stewardship continues. “Part of the master plan was recognizing that maintenance will be necessary,” says Waslaski. “The stonework is a perfect example.” The plan calls for assessment of the stone every five years. And the Preservation Commission is scheduled to continue to meet annually.

In the meantime, all involved can pause and share a moment of pride. “Now the capitol is doing exactly what the original building was meant to do—to inspire Minnesotans, especially kids, with art and architecture,” says Waslaski.