In her whimsical installation, she plays with dolls

Installation artist Misaki Kawai missed the open studio event a few years back at which her boyfriend, artist Taylor McKimens , welcomed visitors into their space in New York's Chinatown. But she's eager to share what people said when they saw her art.

"Taylor said, 'This is my work, and that's my girlfriend's,' " Kawai says. "People who came in wanted to know, 'How old is your girlfriend? Eight?' "

It's a natural mistake. Kawai's work -- her "Momentum 7: Misaki Kawai" opens at the Institute of Contemporary Art today -- has the unmistakable stamp of an elementary school arts-and-crafts project.

The installation, called "Space House," is fashioned from papier mâché, wood, and fabric. It's a sprawling series of dollhouses surrounded by monorails, suspended from the gallery's ceiling. The dolls that inhabit it are roughly made, with shocks of fake fur for hair. Bright paint covers the outer walls, with smudges and accidental spatters here and there, in a palette that kindergartners would love.

Despite its amateurish appearance, "Space House" is a marvel. It's electrified, with lights and working video monitors, airing shows that star Kawai's dolls. There's a hot tub, a room just for cats, a gym, and a helipad. Her tiny paintings hang on the walls.

The artist, 29, is winsome and engaging, full of stories, observations, and questions. Her playful work, sweetly populated by dolls and stuffed animals and inflected with a puckish sense of humor, reflects her personality.

The giant dioramas she makes -- they're not all houses -- spring from seeds planted in her childhood. Her mother makes puppets; her father is an architect. Kawai grew up in Osaka, Japan, and moved to New York after art school.

"In Japan, I was just making the dolls. I didn't think of installation until I came to New York and saw contemporary art installations," Kawai says. "I started to think on a bigger scale."

She has hit it big in the last four years, first in New York, then internationally.

"There's a joy in the making," says the ICA's assistant curator, Emily Moore Brouillet , who organized the show. "It's like when you're a child. You're not thinking about why you're making something. You're just making what you love. And I like the aesthetics, the rough quality. She's not worried about being polished, but there is this insane amount of detail."

On Saturday, four installers whizzed about the gallery on scissor lifts, adjusting the elements of "Space House," which hangs on fishing line from a grid on the ceiling. Boxy extensions to the central dollhouse sat on the floor, waiting to be strung up. Colorful monorails lay like kindling in a rough stack. A doll on what will be an airborne version of a Jet Ski was perched atop them. Many of the dolls represent the artist, her friends, and folks she'd like to know -- such as the Beatles. A nude John Lennon warms up in the "Space House" hot tub.

One of the installers is McKimens, Kawai's lanky artist boyfriend. They always help with each other's installations.

"It's good and bad," she says of having him in on most installation efforts. "This [one] is mellow. Usually, there's no sleeping, drinking a lot of Red Bull, not eating much."

Although her work is strictly her own, she doesn't hesitate to recruit help for some of the more menial construction tasks, such as gluing fabric to the wooden walls.

Kawai's mother helped her put together "Space House." The artist constructed the piece last year in a studio a few blocks from her parents' home in Osaka, for a show at the Watari Museum of Contemporary Art in Tokyo. Compared to Kawai's goofy dolls, she says, her mother's work is fastidious.

"Hers are more nice and well done," Kawai says. "She makes clothes, and they have to be perfect to fit the body. But if I made pants myself, they're uncomfortable."

That's not self-criticism. While they might not be fun to wear, those hypothetical pants are more interesting and offbeat, Kawai suggests. "My art is what they call in Japan 'hetauma,' " Kawai points out. "It means 'it's bad, but it's good.' "

Her mother doesn't mind her daughter's different aesthetic. "My mom knows what art is like, so she understands," Kawai says. The light, fun, and childlike qualities of Kawai's work echo that of Shintaro Miyake , whose "Beaver No Seikatsu" at the Massachusetts College of Art last year entailed the artist genially walking around in public wearing a giant beaver costume. The two also share a disregard for the kind of meaningfulness that can make art great, but can also occasionally sap the joy out of it.

"Some people take art too serious," says Kawai. "It doesn't have to be so complicated. . . . I want people to feel good and to have fun."

"Momentum 7: Misaki Kawai" runs at the Institute of Contemporary Art, 100 Northern Ave., through July 8. 617-478-3100. ica.boston.org.