After they buy a century-old house, most homeowners undertake improvements, such as upgrading the electrical system, refinishing wood floors, and repairing and painting plaster walls. The first thing Bob and Sue Greenberg did after purchasing their 1906 Lowry Hill mansion was to convert an old root cellar into a basement sauna.

"We had one in our old house and really liked it," said Sue.

But after that, the couple went on to complete a very long list of projects, ranging from replacing pieces of the clay tile roof to a complete kitchen makeover.

Back in 1991, the year the Greenbergs bought the home, they fell in love with the stately yellow brick beauty, with hints of Italian Renaissance architecture, on Mount Curve Avenue in Minneapolis. "When we stood in the foyer and saw the gorgeous woodwork and painted glass, we knew we wanted to live there," said Sue.

The house was originally built for Charles Gluek, a member of the Minneapolis brewing family. Overall, the home had remained solid, but parts were beginning to deteriorate after nearly 100 years.

On the exterior, the Greenbergs rebuilt the crumbling chimney and front veranda, and did extensive tuck-pointing and repair on the brick facade. "When we refurbished the clay tile roof, the hardest part was scouring salvage yards to find replacement pieces," said Bob.

They upgraded the electrical system and added central air-conditioning. A previous owner had enclosed part of the veranda and turned it into a three-season porch. The Greenbergs put in new windows and heated floors to transform it into a cozy sunroom with a view of Thomas Lowry Park. They also combined two upstairs bedrooms to create a luxe master suite.

Most recently, in 2012, the couple gutted and renovated the dated 1980s kitchen, blending the new with the old, while remaining true to the home's original charm and character. "We did a lot to modernize the mechanical systems and make the home more functional without damaging the features that make it special," said Bob.

On the second-floor landing, a stained-glass depiction of the sculpture of Hiawatha and Minnehaha isn't original to the house, but adds to its vintage character. The Greenbergs hired an artisan from Gaytee Stained Glass to modify the panel so they could open the double-hung window. "Of all the projects we did, we [initially] thought it was a waste," said Sue. "But the first time we opened the window, it was awesome when the air flowed in."

The empty-nesters, who run a company that owns and manages commercial real estate, now plan to travel more and simplify their lives. "We haven't started looking yet, but we want to stay in Minneapolis — and get a place that we can lock and leave," said Sue.

Other features:

• The 7,130-square-foot mansion has four bedrooms and five bathrooms.

• Many of the original features are still intact, such as light fixtures and a glass-tile fireplace surround.

• The dining room's large built-in buffet boasts period patterned leaded glass.

• The carriage house has a second-floor apartment with one bedroom and one bathroom.

• The lower level houses a family room and bar.

• The third story could be an in-law suite with a bedroom and living room.

• Location, location, location: The home is across the street from Thomas Lowry Park, near the Walker and neighborhood restaurants. Bob Greenberg walks to his office on Nicollet Mall.

Laura Tiffany of Coldwell Banker Burnet has the listing, 612-924-4386.

Lynn Underwood • 612-673-7619