While many baby boomers downsize as they grow older, documentary filmmaker Aviva Kempner counterintuitively went bigger. Way bigger.

She gained 800 square feet of living and party space, not including the basement and attic she finished later, by moving from a Chevy Chase, D.C., duplex to a Forest Hills Colonial large enough to contain her multiple collections, her filmmaking enterprise and her wide circle of friends, family and colleagues.

The Northwest Washington house and its nearly quarter-acre lot, bought with an inheritance from an uncle who survived Auschwitz, met all of her exacting requirements.

“First, I wanted to age in place and never move again. They’ll have to carry me out of here in a box,” says Kempner, 68, citing the new elevator that links her lower-level office to the first and second floors, and the outdoor ramps, front and rear, to be used when she can no longer navigate stairs.

Kempner also wanted expansive entertaining spaces. A frequent host of gatherings large and small, she can now welcome 100 guests inside or outside, at events as disparate as book parties, bar mitzvah receptions, political meet-and-greets, potluck buffets, seated dinners, movie screenings and even a memorial service. (At a recent fundraiser for Maryland Democratic congressional hopeful Jamie Raskin, the ramps intended for her dotage proved helpful to a 20-something with a broken leg and an 80-ish gent leaning on a cane.)

There had to be enough wall space for the oversize abstracts by her late mother, artist Helen Ciesla Covensky , along with Kempner’s own impressive collection of photos, etchings, drawings, sculpture, ceramics, paintings, tiles and textiles by numerous artists, nameless to famous.

Her filmmaking enterprise, the Ciesla Foundation , had to fit into the basement that she finished to include a surprisingly bright three-room suite where young staffers research, edit and schedule showings of her films.

All five of Kempner’s documentaries, including a well-received biopic about baseball great Hank Greenberg , have some connection to Judaism. Her recent release, “Rosenwald,” which scored a 95 percent positive rating on Rotten Tomatoes, focuses on former Sears, Roebuck president Julius Rosenwald of Chicago, who worked with Booker T. Washington to help African American communities build more than 5,300 schools in the brutally segregated South (several of the interviews were shot in Kempner’s living room).

In addition to copious living and exhibit space, Kempner wanted custom metal- and tilework that would pay homage to Antoni Gaudí, the Catalan architect famed for his use of sinuous ironwork, intricate mosaic and stained glass throughout Spain, and to the vivid colors of her mother’s art. Kempner also sought to showcase handmade tiles from the Middle East, Europe and the Americas.

The eight-month renovation was sufficiently complete in 2011 for Kempner to move in and start to decorate and curate what easily could be an intimate house museum: elaborately carved antique French china cabinets and sideboards, and charming primitive folk pieces, modernist leather furniture and carefully chosen pieces of Judaica, baseball and political memorabilia.

For those who dwell at the beige-and-pastel end of the spectrum, and for minimalists who believe less is more, Casa Aviva can be overwhelming. But the blunt-spoken chatelaine has always lived out loud, and the house reflects its owner’s many passions.

Katja Tenenbaum, a friend from Rome, was struck by Kempner’s style, which reminded her of the way artworks and artifacts are grouped at Philadelphia’s Barnes Foundation. “When you fix your attention here, you realize how things are arranged, and you are surprised by the unity of the personality and spirit of Aviva and her collections. You have to concentrate, and you need more than one visit.”

Candidate Raskin called the house “completely enchanting. It was like the first time I saw Mardi Gras, full of color and pizzazz and exuberance.”

In tony Forest Hills, where a 1994 mansion near Kempner’s home carries a $22 million price tag, not everyone delights in the transformation of her grassy front lawn into a Gaudí-esque sculpture garden complete with a five-foot painted hand meant to promote D.C. voting rights.

A statue in the front yard promotes D.C. voting rights. Behind it is a mosaic set into a walkway. (John Magor/Special to The Washington Post)

The mosaics continue around to the back yard; they and the metalwork pay tribute to Antoni Gaudí (John Magor/Special to The Washington Post)

“It’s very different than the neighborhood,” comes the occasional murmuring. “It stands out. It’s not subtle.”

“If anyone is unhappy, they’ve never told me,” said Kempner.

The daughter of a Polish mother who passed as a Catholic in a German work camp, and a Lithuanian-immigrant father who served in the U.S. Army in postwar Germany, the Berlin-born Kempner arrived in Detroit at age 3. By 1973, she’d moved here to attend the Antioch School of Law (now part of the University of the District of Columbia) but switched to film after failing the bar exam. Along the way, the vocal social justice activist worked hard to bring major league baseball back to Washington and continues the uphill battle for D.C. statehood.

To help execute her singular vision of home, she gave much-appreciated creative license to three artisans who have worked for her over the years, including Axel Vasquez, 25, and his brother Byron Vasquez, 31. After Kempner showed them books of Gaudí’s work, especially Barcelona’s Park Guell, Axel, a self-taught mosaic master, tiled parts of the walkways, stairs and retaining walls built by Byron. Meanwhile, her longtime landscaper, Donald Redditt of Accokeek, Md., came alive when Kempner asked him to paint her kitchen cabinets the same steely, tealy sage of a primitive Amish cupboard. Instead, he faux-finished them in what seems like 50 shades of blue.

“Clearly he had other ideas, and I loved it,” said Kempner.

The trio’s handiwork starts at the curb, where Axel’s mosaics are sunk into Byron’s brick and concrete pathways, which then wind past Redditt’s flowering shrubs, trees and potted plants, to continue around the house to the back. There, more mosaics brighten walkways, walls, tables and birdbaths.

Enter the bright-blue front door and the first thing one sees is a curved staircase that spirals up two levels. On the ascending wall are three of pro baseball’s most famous Jewish players — catcher and coach Moe Berg, southpaw pitcher Sandy Koufax and, of course, super slugger Greenberg — rendered in wool by fiber artist Leslie Kuter, who lived in Washington from the 1970s to the ’90s.

To the right of the stairs, a pair of intricate wrought-iron gates from Kempner’s childhood home opens to the living room. Cream walls are trimmed in red, the better to show off a fireplace framed in contemporary American tiles made to look as if they’d been rescued from some grand art nouveau mansion.

The living room, painted cream with red trim, displays family antiques and art by Kempner's mother, Helen Ciesla Covensky. (John Magor/Special to The Washington Post)

The Gaudí homage is repeated at the rear of the living room: swirling ironwork visible through windows and custom wooden doors that create a visual link to the patio. To the left is the dining room, its walls and ceiling painted a muted blue. The table can seat 14 in a pinch but is more often laden with food brought by friends content to eat potluck fare while ogling the interiors.

The adjoining kitchen, with its cream walls, boasts a navy sink and lighter blue tiles trimmed in florals and geometrics on the counters and floor. One set of ceiling-hung blue-hued cabinets has glass doors on both sides, through which hand-glazed Armenian dishes, most in patterns of azure, are visible. Outside the kitchen is a Big Green Egg cooker, set into a tiled framework that draws heavily on folk motifs from the Vasquez brothers’ native Guatemala.

Kempner spends much of her time in a cozy green study to the left of the entrance. But the second floor is her refuge, with the master bedroom painted a deep rose and cream, and filled with Victorian, art nouveau and art deco furnishings and lighting. A door at the far end of the room opens to reveal another salute to Gaudí, a wrought-iron Juliet balcony overlooking the back yard.

Here, “I lie in bed and feel like I’m in a treehouse,” she said.

The adjoining master bathroom, which features large Armenian tiles depicting nature motifs on the floor and walls, offers passage to yet another bedroom that she converted into her dressing space. A guest room and a study complete this level.

One flight up is a finished attic that could become a sitting or sleeping area, were it not crammed with unpacked boxes. The elevator, too, is filled with papers “and will probably stay that way until I can no longer walk and actually need to use it.”

And she intends to use it. “This is the house I always wanted,” Kempner said. “And this is the last place I plan to live.”

Annie Groer writes about design, politics and culture. Her last piece for the Magazine was about the National Children’s Museum.

E-mail us at wpmagazine@washpost.com.

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