The busy corner of Interstates 70 and 25 will be the site of a new residential, retail and office campus that developers hope will remake the image of an intersection known as the traffic-jamming Mousetrap.

The $100 million project, on the grounds of the former Denver Post printing plant, is driven by high design — from its architect, the internationally renowned Brad Cloepfil, who created Denver’s sleek Clyfford Still Museum, to its featured tenants, commercial and residential designers who will locate their showrooms in the main building.

But if all of Denver-based Ascendant Development’s plans are realized, the 41-acre parcel also will include multi-family housing and a newly constructed building that will host collaborative office space for small, creative-sector businesses.

“This will cross over into art, fashion, food,” said Ascendant partner Graham Benes. “We are developing a whole design neighborhood.”

The area has been primed for renewal lately. Highway improvements have eliminated the once-notorious rush hour congestion. More important, the imminent expansion of RTD’s light rail line northward will deliver a stop at 41st and Fox streets, just two blocks from the project.

Still, rebranding the site, which remains in a neighborhood of manufacturing plants and warehouses, required a bold move, and that’s where the big-name designer came in.

“We knew we’d really have to up our game if we were trying to say we are a regional destination,” said Benes.

In addition to the 16-month-old Still Museum, Cloepfil’s Allied Works Architecture is responsible for the 2007 expansion to the Seattle Art Museum and the 2008 renovation of the Museum of Arts and Design on Columbus Circle, across from New York’s Central Park. The firm has completed several commercial rehabs of older buildings as well.

Cloepfil said Tuesday that he was drawn to the 25/70 project because the idea of a whole design campus was something that hasn’t been successfully explored.

“The site is spectacular,” he said. “And it’s always fun to do something new and challenging.”

The design scheme is still in the works, but Cloepfil said one objective is to “weave the outdoors” into the giant, block building that has few windows by incorporating “air, courtyards, light and alleys.”

“We are carving it and cutting it up.” he said.

The project reunites the architect with Saunders Construction, the local firm that helped his vision of giant, single-pour concrete walls become a reality at the Still Museum.

The project’s first phase is a $75 million renovation of the existing former printing facility into the design center, said Benes. That will require adding 65,00 square feet of mezzanine space to the existing 320,000-square-foot structure.

Ascendant purchased the building in 2008 from the Denver Newspaper Agency for $17 million after the agency moved to printing operations to 5990 N. Washington St.

Benes said the site would also include retail and restaurant space to create a multi-dimensional facility for design professionals that “has energy and is an experience for their clients, not a place that’s boring and dark.” The addition of offices for architects and interior designers would allow a synthesis between professionals with overlapping services and customers.

The project’s second phase would add a residential component on 10 acres of the site within the next few years. Between 250 and 500 units will go up, Benes said.

The third phase will be a new, 90,000-square-foot building with flexible work areas, leased to tenants who would share common areas, office equipment and links to technology.

Ascendant, which is completing the project with private, borrowed financing, has worked with local design firms on its other projects. The national search that ended with Cloepfil’s firm “took longer and was a lot more expensive” than other efforts, Benes said. But Cloepfil brings a certain panache to 25/70.

And those costs were balanced by the affordable real estate in an emerging section of the city.

“It’s still affordable compared to across the way in Highlands,” said Benes. “The growth has to come out this way and we’re still in the beltway area.”

Ray Mark Rinaldi: 303-954-1540, rrinaldi@denverpost.com or twitter.com/rayrinaldi