A Glass House Built Around a 19th-Century Facade Enda Cavanagh for The New York Times The new funnel-like entrance to Ella Flynn's home lends grandeur to the modest opening in the historic facade, which could not be changed. AN old architectural sleight of hand stands at the center of Ella Flynn's sleek, modern home in Dublin. In 1847, when a Georgian row house was built near the front of the lot, privileged landowners "wanted to look out on something lovely," she said. So a neo-Classical false front was created to mask the utilitarian carriage house with the servants" quarters at the far end of the garden. By 1966, when Mrs. Flynn, now 77, and her husband acquired the property, for about $20,000, the horses, coaches and servants were long gone, and the main house had been split into apartments. In this upscale neighborhood on the city's Southside, humble mews buildings were a half-forgotten footnote until the 1980s, when owners began transforming them into coveted homes. The Flynns, though, left theirs unchanged. They had bought the property with the idea of living in the main house. But after Dr. Flynn trained as an ophthalmologist in the United States, they settled permanently in Pasadena, Calif., where they had five children. Still, they returned to Ireland regularly. "We wanted our children to know their roots," Mrs. Flynn said. They rented out the apartments but found ways to stay there between tenants, often for entire summers. And when the children eventually had families of their own, the Flynns decided to build a family retreat on the site of the deteriorating coach house. Under landmark protections, they were permitted to tear it down, but the false front had to stay. And any additions needed to look modern, in obvious contrast to the old. The couple embarked on the project, but when Dr. Flynn became ill and died in 2005, his wife put the plans on hold. Later, she revisited it with the help of her fellow Irish expat, the Los Angeles architect Lorcan O'Herlihy, an established modernist whose parents she had known. He had never built in Ireland and leapt at the chance, particularly on a site a few doors from his mother's girlhood home. Leaving the historic facade unencumbered, Mr. O'Herlihy created a 2,900-square-foot house made up of two free-standing volumes joined by a glass-enclosed bridge - hence Mrs. Flynn's name for it: Bridge House, or Tighe an Droichead. Mr. O'Herlihy also experimented with charcoal-tinted board-formed concrete and local masonry, choosing, he said, "not to export the culture of L.A. to Dublin." Instead, he created a riddle-like entry sequence that plays off the original architectural ruse. From the mews, you cross a series of thresholds: through a steel-paneled gateway in a stone wall and across a parking court to a concrete facade with a funneling entryway. In an Alice-in-Wonderland moment, the entry converges to a modest door that leads, surprisingly, outdoors again. That's when you discover you've just passed through the historic facade. Then you traverse another small courtyard before you finally step indoors, into a glassy volume housing the kitchen, dining and living areas, and two bedrooms (two others are above the funnel). Inside, zebrawood and white marble define a "kitchen that isn't kitcheny," Mrs. Flynn said. It's elegant, exactly as I like it. Mrs. Flynn currently divides her time between California and Ireland, where her offspring join her en masse. The mews house is strikingly unlike her antiques-filled Spanish-style Pasadena home, but as she noted: "At the outset, I thought I was uncomfortable with modern architecture. Now I love it.