In 1960, when he was an unknown 31-year-old architect, Hugh Newell Jacobsen designed his first house on the edges of Cabin John Park in Bethesda, a mid-century modern residence tucked into the hillside, with expanses of windows overlooking forested land.

Fifty-seven years later, Jacobsen, who became revered in Washington for his bold modernist style, is back at the house. The home today is larger but very much still a tribute to the style for which the architect, now 88, made his name.

“Nice house!” Jacobsen says as soon as he is inside the door. “It must have been a brilliant architect.” He smiles.

Owners Ted and Ruth Kassinger, 64 and 62, look relieved. There was no telling what Jacobsen would say. The original owner, Harold Tager, had in 1965 added an unusual “floating” second floor, designed by George Hartman, another acclaimed Washington architect. Then, just two years ago, the Kassingers gave the place a total overhaul, hiring architect Ben Van Dusen to add a library, settle the second floor, put in new windows and take the rest of the place down to its studs.

Before the Kassingers bought the home in 2014, it was tear-down material; after years of neglect, it was full of water damage, with the second floor slowly sliding right off the roof.

Even so, Ruth Kassinger says, “When I saw it I thought, this was my house.”

Before Ted and Ruth Kassinger bought the home in 2014, it was tear-down material. (Stacy Zarin Goldberg/For The Washington Post)

Kassinger, a science and gardening writer, had reason to see beyond the damage. She had been a fan of Jacobsen’s since she was a teen. One of her childhood friends had lived in another of his designs, the townhouse complex called Bolton Commons in Baltimore. “Even as a teenager, I knew that the design of the townhouses was something special,” she says. When she saw a real estate ad for a Jacobsen-designed house, “I had to stop by and see it.”

Even with extensive changes, the Kassingers were hoping for the approval of the somewhat famously outspoken architect. (Jacobsen recalls once responding to clients’ requested changes: “Look, I’m the architect. I won’t accept that if my name is on it.” After telling me this, he adds, “My ego is as big as all outdoors.”)

But on this day, Jacobsen, accompanied by his son and partner, Simon, is charming and chatty. This renovation employs the best instincts of modernist design: enormous windows looking out over a Zen-like landscape, clean lines, no clutter and an interior carefully decorated with a collection of authentic and reproduction mid-century furniture.

Architect Ben Van Dusen’s work on the house included the addition of a library with a bookcase done in the boxy egg-crate style that Jacobsen created. (Stacy Zarin Goldberg/For The Washington Post)

Jacobsen is brought into the library, an addition designed by Van Dusen. “Wow,” he says. “Well, isn’t this a nice room?” Jacobsen notes every detail: the bookcase done in the boxy egg-crate style that Jacobsen created; a right-angled corner window peeking out from the shelves, looking like something Frank Lloyd Wright would have envisioned; and floor-to-ceiling windows on two sides.

For the most part, though, the house is Jacobsen’s vision. Just out of Yale architecture school in 1955, he apprenticed with Philip Johnson in New Canaan, Conn. It’s no surprise, then, that when Jacobsen started on his own firm in Washington, his clients might have imagined they were getting something designed in Johnson’s iconic glass-house style.

Jacobsen recalls meeting the original owner, Tager, at a dinner party. “I had worked for Philip Johnson, and he knew that,” Jacobsen says. “And he wanted a Philip Johnson house. He didn’t want a Jacobsen house. And I had to work very hard to make it mine and not Philip Johnson’s.”

Hugh Newell Jacobsen (Nathan Coe)

Jacobsen knew this first house would be his big chance. “I wanted this house to be more important than the Farnsworth House,” he says, referring to the steel and glass home designed in the late 1940s by Ludwig Mies van der Rohe in Plano, Ill.

Later in the 1960s, Jacobsen moved on to the triangular gabled roofs and vernacular style for which he’s better known. In 1998, he designed a “Dream House” for Life magazine as part of the publication’s effort to bring affordable design to the masses. At the time, a plan for the Dream House, which looks something like a child’s vision of a simple white farmhouse, cost about $600. A newer version of those plans is still available today, for about $3,000.

Jacobsen’s work has also included Jacqueline Kennedy Onassis’s home on Martha’s Vineyard, a remodel of the American Embassy chancery in Paris and a restoration of the 1735 farmhouse in West Virginia owned by D.C. journalistJim Lehrer and author Kate Lehrer. “He just can do magic with his houses, with his designs,” Kate Lehrer says.

The Kassinger home had good bones but more damage than immediately met the eye. “The place was hanging by a thread,” says Van Dusen, 62. The 1965 addition created a two-foot gap between the two floors, which eventually allowed water to seep in. Van Dusen closed the gap by raising the living room ceiling.

Jacobsen’s version of the home had eight-foot ceilings throughout. “I think that the aesthetic was almost like taking a Mondrian painting,” and then “elevating that grid with very simple walls and flat ceilings,” Van Dusen says. The modern update added windows on the higher grid to bring in more light.

The rest of the house continues the Mondrian-modern sensibility. At the front, a wide slate walkway is suspended over a stone-lined pool, with fountains creating a soft welcome. The entrance is a typical modernist understatement: The front door opens to face a blond brick wall, leading a visitor to veer either right, toward bedrooms, or left, in the direction of the kitchen.

Jacobsen’s version of the home had eight-foot ceilings throughout. The modern update added windows on the higher grid to bring in more light. (Stacy Zarin Goldberg/For The Washington Post)

A large living room looks out to a substantial screened-in pavilion and boxwood-lined grounds originally designed by Lester Collins, the landscape architect who also worked on the National Zoo. Landscape architect Richard Arentz handled the recent renovation of the property.

One detail carefully preserved from the original house was the doorway separating the living area from the dining room, with large sliding pocket doors. Jacobsen immediately notes this on his visit.

In the master bedroom, which was completely remodeled, Jacobsen zeros in on a white built-in dresser. “That looks like mine,” he says.

Ruth Kassinger responds, “No, but I knew what you’d want.”

“That’s a client I like.”

He reminisces about the process. “Boy, did I worry about this. I was here about every 20 minutes,” he says. After it was done, “people used to line up to peek at it down the driveway.”

“I was — and still am — extremely proud of this.”

That pride is also pleasing to Van Dusen. “I knew going in that it would be solidly deferential, but not completely,” he says. Finding out that the second floor was done by George Hartman only added to the intrigue. “For me that made it more interesting,” Van Dusen says. “I wouldn’t say it was intimidating, but I knew going in that the [library] addition would have to be somewhat deferential. But at the same time, you want to make something of a mark.”

Though Ruth Kassinger is a science and garden writer, the home is virtually plant-free except for two vertical plant boxes incorporated into the library wall, under skylights. (Stacy Zarin Goldberg/For The Washington Post)

The renovation isn’t the first time the Kassingers have undertaken a large-scale project. Before they bought this place, the couple added a Van Dusen-designed greenhouse to their former Bethesda home, a project that Ruth Kassinger detailed in her book “Paradise Under Glass,” a sweeping story that covers the history of greenhouses, the plants she grew and personal losses that led her to a loving obsession with conservatories.

This home is virtually plant-free except for two vertical plant boxes incorporated into the library wall, under skylights. But in a larger sense, Kassinger still has her roots in the plant world; she’s surrounded by Cabin John Park and those windows that show each season.

“In the summer, the grass is clover and the deer come,” says Kassinger, “including fawns who come right up to the window.” Her other visitors include a pair of foxes who circle the property every morning around 8.

Van Dusen, who has become a friend of the Kassingers’, muses that because Ruth’s next book is a deep delve into algae, she might have to incorporate a nod to algae in her modernist home.

More likely, though, this Hugh Newell Jacobsen house will remain a simple and clean nod to its creator — as Kassinger says, “an act of homage to a wonderful architect.”

Debra Bruno is a freelance writer based in Washington.