After his widow died, in 1941, the house stood empty until Mr. Wood and his wife came upon it. The story, Mr. Wood said, is that Mr. Wharton’s three sons disliked one another so much, they couldn’t agree on who to sell it to. “I think they only sold it to me because I was a relative,” he added.

Every spring for a decade or so after the sale, Mr. Wood said, he cursed “this albatross,” his roofless, windowless, floorless, powerless, waterless house. Wrangling what had been a rich man’s plaything, attended by servants and even its own shipyard, into a working couple’s weekend getaway turned out to be much more than a working couple could handle. Eventually, though, as the Woods mustered the talents of their friends, Clingstone and its maintenance evolved into a communal lifestyle, and ultimately a kind of religion.

Mr. Wood is now as proud as any parent of his house, and keeps a fat scrapbook of photographs and newspaper clippings that document its best moments. He has been known to buttonhole strangers on planes who express a knowledge of Rhode Island and say, ‘I think you know my house,’ and then fall silent, waiting for them to exclaim: The house on the rock! Once, he persuaded an airline pilot on a commuter flight from New York City to Boston to alter course to the east so the plane would fly directly over Clingstone.

To get to this point, Mr. Wood became an expert scavenger, a deft barterer and an experienced arm-twister. “The number of things I’ve gotten for free,” he said happily, ticking off the 60 black porcelain doorknobs salvaged from houses that were being torn down in Boston’s South End; the overhead factory lights that came from a slaughterhouse in lower Roxbury; the lumber plucked from an old Boston-area supermarket and strung with netting to make the railing that runs around the stairwell on the second floor. (There are still no banisters on the wide, twisting main staircase, though the father of a man who was married here carved the banister posts for the back stairs.)

In those first years, friends came to work and camped for weeks. The biggest worry, Mr. Wood said, was that there wasn’t any way to lock up: “We lost a lot of tools, and one brass bed.”

One year Mr. Wood put an ad in The Harvard Crimson: “Island occupant wanted to live in 23-room house. No charges. No duties. Ready now.” Somehow, The Crimson printed that last line as “Leaky now.” Still, Mr. Wood was able to “hire” his first caretakers, a doctoral student and his wife, who would stay at Clingstone during the week and head back to Boston when Mr. and Mrs. Wood arrived on the weekends with their three young sons: Paul, now 45 and an employment discrimination lawyer in Boston; Josh, 41, an architect there; and Dan 38, an artist and printer living in Providence, R.I.