William Cahill of Cincinnati thatches a roof on one of three huts made from stumps of a 227-year-old white oak in the Bookworm Glen section of the Pittsburgh Botanic Garden in North Fayette and Collier.
William Cahill, a thatcher who was born and trained in Galway, Ireland, used vines removed from trees at the Pittsburgh Botanic Garden to add a decorative and functional touch to thatch roofs on huts made from a downed 227-year-old white oak.
By Kevin Kirkland / Pittsburgh Post-Gazette
William Cahill has thatched roofs all over the world, from his native Ireland to Africa and in this country from Boston to California. His first time in Pittsburgh, we put a roof over his head.
“It’s customary to put up the thatcher in Ireland and England,” he said in a soft brogue. “Pittsburgh certainly put out the welcome mat. I felt like I was in Ireland. People were very easygoing and friendly and inquisitive.”
Mr. Cahill spent two weeks in November at the Pittsburgh Botanic Garden, thatching conical roofs over three massive stumps from a 227-year-old white oak tree. When he wasn’t thatching, he was sightseeing and staying at the South Side home of Jeff Neubauer and Kitty Vagely, the garden’s director of development.
Thatching at the Pittsburgh Botanic Garden
William Cahill of Cincinnati, Ohio, speaks about thatching a roof onto one of a series of huts made from stumps of a 227-year-old white oak in the Bookworm Glen section of the Pittsburgh Botanic Garden in Oakdale on Monday, Nov. 23, 2015.
“It was a wonderful treat for us,” she said. “He was so knowledgeable.”
Mr. Cahill, who says he’s in his fifties, is one of only two real thatchers in the U.S. (http://roofthatch.com) After a five-year apprenticeship in Ireland, he came in 1986 to thatch roofs for recreated 17th-century cottages in Virginia’s Jamestown Settlement at the behest of the Smithsonian Institution. He met and married an Ohio girl and settled in Cincinnati. (“Aren’t they your rivals?” he joked.)
Over a 35-year career, he has traveled the world, attaching, dressing and cutting water reeds to create a smooth, natural roof. He uses the European technique, he said, yet thatching is a near universal craft that developed about 4,500 years ago in places as far apart as China, England and Choctaw Indian villages in the Dakotas.
Mr. Cahill credits 18th-century French thatchers in Normandy for the Cottage orné style that is most popular today. Both functional and beautiful, sometimes with flowers growing on the ridges, it’s the look he strives for in projects ranging from small garden sheds in New York and California to mountain pavilions and guest cottages in North Carolina, Utah and Colorado.
He typically uses reeds he harvests himself every winter on conservancy-owned wetlands in Delaware and New Jersey. But for the Pittsburgh Botanic Garden project, he used cattails harvested near the 460-acre tract in North Fayette and Collier. Mr. Cahill prefers to use locally sourced materials because they’re more environmentally sustainable and because he believes they stand up better to the weather.
His American roofs are steeper -- about 50 degrees -- than the 40-degree roofs he made in Europe, a concession to our heavier snows and colder weather. They’re usually 9-12 inches thick and can last up to 30 years in our climate, much longer in milder ones.
The tree village he thatched in Bookworm Glen was only the second one he had done. The first was a tulip tree hut for Winterthur’s Enchanted Wood in Wilmington, Del., several years ago. Pittsburgh Botanic Garden president Greg Nace saw it and asked Mr. Cahill to do the same with a huge oak that fell here.
Board member Justin McElhattan of Industrial Scientific got the project started with a $10,000 grant; about $5,000 of that paid for the thatched roofs. FedEx Ground is helping to fund the rest of the $19,000 cost.
Before Mr. Cahill arrived, botanic garden volunteers led by horticulture and facilities manager Benjamin Carroll built roof framing from pressure-treated pine. He and others plan to add doors and other details to the huts.
Mr. Cahill, who has worked on centuries-old roofs in his hometown of Galway, hopes to still be thatching when he is 89, like Piper Riley, one of the masters who trained him.
“He used to say, ‘I’ll retire when I’m not able to do it.’ That’s my attitude, too. I’ll go to the end.”
Kevin Kirkland: email@example.com or 412-263-1978.
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