Living Apart Together - NYTimes.com Kendall Waldman for The New York Times Ingrid Doyle and Michael Kenny share a life together, but not an apartment. The mantel is at her prewar co-op in northwest Harlem. Mr. Kenny's living room in South Harlem, 30 blocks away, has a different aesthetic. With housing in New York City an increasingly scarce and costly commodity, and under the hoary "two can live as cheaply as one" rule, logic would seem to dictate that couples would move heaven and earth to place themselves under a single roof. Brad Harris for The New York Times Robert Fontanelli, left, and Rolf Sjogren in Mr. Fontanelli's living room in Gramercy. Many people set up housekeeping together simply to help foot the rent bill. But some couples, both those in longtime relationships and the officially married, follow a less-traveled path. They live in separate homes - on different floors of the same building, down the block from one another, in different neighborhoods, even in different boroughs. Some who go this route contend that separate spaces not only reduce friction in a relationship but keep it lively, even sizzly, freed from such mundane concerns as whose turn is it to empty the dishwasher and by the way, did anyone pay the rent? Especially for older New Yorkers, more set in their ways, the idea can offer considerable allure. Perhaps each person cares passionately about living in a certain neighborhood and neither wants to compromise. And after multiple marital breakups, the world of joint mortgages and matching towels may hold little charm. In a city in which even shoebox-size apartments carry hefty price tags, real estate calculations play a critical role. Who dares jettison a rent-stabilized Classic 6 or an affordable space in a pricey neighborhood like the Village? And how many people can squeeze into a studio the size of a pantry? A recent blizzard of statistical studies and two newish books - "Living Happily Ever After - Separately" by Lise Stryker Stoessel and "Going Solo: The Extraordinary Rise and Surprising Appeal of Living Alone" by Eric Klinenberg - document what sociologists call living apart together, or L.A.T. "The arrangement has surprising appeal, perhaps because it protects against the constant churning in people's domestic lives," said Mr. Klinenberg, a sociology professor at New York University. Many people who live alone are in relationships that are quite meaningful. And the arrangement is especially attractive in New York, which has such a thriving public culture and little stigma about how people live their lives. A common reason couples live under separate roofs is that they've always done it that way, making the arrangement less a conscious decision than confirmation of the status quo, as it was for Michael Kenny, 62, a lawyer with Citigroup, and Ingrid Doyle, the woman with whom he shares his life. They met in an unlikely setting - the dentist's office. She was a hygienist, he was a patient, and they've been a couple since shortly after their first date in 2000, albeit rooted to separate and stylistically opposite habitats. His is a rent-stabilized two-bedroom in a rehabilitated tenement on West 116th Street in South Harlem, his home since 1997, for which he pays under $2,000 a month. Much of the furniture is vintage golden oak dating back to his undergraduate years at Brown. "Because let's face it," Mr. Kenny said, "I'm an old dog." Ms. Doyle, who is about a decade younger, lives more elegantly in a seven-room prewar co-op on West 143rd Street in northwest Harlem that she bought 20 years ago for $25,000. Her space is wreathed with 11 windows, and includes such amenities as a dining room and the outline of a fireplace discovered during a recent renovation. "It wasn't really a decision," Mr. Kenny said of the arrangement. Both he and Ms. Doyle have grown children from previous marriages who are sometimes in residence. "Plus we're not newlyweds," he said. We're grown adults. Despite different addresses, their lives overlap with an easy rhythm. They vacation together. They see each other most evenings, with him usually staying at her place, the tidier of the two. And although some couples who live this way worry about a loss of daily intimacy - the unexpected hug or the soothing words after a bad dream, Ms. Doyle has no reservations about their lifestyle. "It's hard to think of downsides," she said. Sometimes I miss him, but he's just a $7 taxi ride away. He, in turn, walks the 30 blocks to her place or jumps on the subway. And his reservations are minimal. "I miss the casual comfort of being around someone," Mr. Kenny said. But I've lived alone for so many years, I think changing would be hard. I have my ways, my possessions. It's the old saw, that strong fences make good neighbors. A door that can close makes for a good relationship.