If you think adding something as innocuous as an extra half-inch to a nail would not make any difference when building a house, Greg Kopp wants you to think again.
“It’s a surprising little difference. You go from a two-inch nail to a two-and-a-half-inch nail and it doubles the strength,” said the Western Engineering professor, in regards to the sheathing of residential roofs. “Sometimes that’s the difference in making a house resilient, even to tornadoes.”
For a decade, Kopp, along with dozens of students, has spent their days destroying things in the name of science and, more importantly, the name of safety at the Insurance Research Lab for Better Homes (IRLBH). The state-of-the-art research facility, located in a non-descript building near the London International Airport, is currently on its third structure used to conduct experiments on extreme wind effects, moisture penetration and energy efficiency.
Now in its second decade of research, the facility – initially dubbed the ‘Three Little Pigs’ – continues to discover “surprising little differences” while redefining what is considered a safe structure.
Along with the code changes for the length of nails, Kopp continues to work closely with government agencies, the insurance industry and Environment Canada to provide much-needed research for policy changes. While a solid 90 per cent of the work focuses on the roof of a building, the team also looks at siding, windows and doors.
“We want to understand variability with the structure. With sheathing, for example, we probably pulled off plywood panels and did more than 300 tests on them,” he said, using different combinations of thickness of the wood or oriented strand board versus plywood. “We find the little things matter quite a lot. If you lose a piece of plywood off your roof, it’s maybe $50 to fix. But because of that, you get so much rain inside your home that you might lose the contents of your house, which may be upwards of $200,000.”
Their work hasn’t solved every problem, Kopp admitted, namely how to retrofit existing houses inexpensively.
“If we do these things when they’re brand new, it’s relatively inexpensive,” he said. “It’s a ‘do it right the first time’ idea and, if you don’t, it gets expensive when you have to take out drywall and parts of the roof to add the hardware to make it more resilient.”
Kopp also had success with how companies are now testing their products, such as vinyl siding. In strong windstorms, siding comes off routinely. It is one of the insurance industry’s biggest costs in terms of repairs.
“We’ve actually changed the way the siding tests are being done by manufacturers now to ensure they have a robust design for their product,” said Kopp, noting previous tests were using the wrong physics. “Product manufacturers have different test standards they have to meet for their product in order to sell them, but they don’t really think about the wind. It’s also about how they’re fastened on. We fixed that.
“Individual companies benefit; the companies in southwestern Ontario that are manufacturers of these products benefit; customers benefit. Everything we do benefits everyone who owns a house.”
Western has been a leader in wind research for more than half a century.
In 1964, the Boundary Layer Wind Tunnel Laboratory was constructed. Initially led by Engineering professor Alan Davenport, the facility tested – and continues to test – many of the tallest buildings and largest bridges in the world, including the World Trade Center in New York City, the Sears Tower (now the Willis Tower) in Chicago, the CN Tower in Toronto and the Tsing Ma Bridge in Hong Kong.
In 2005, Western built the Insurance Research Lab for Better Homes. Since, the university added the Advanced Facilities for Avian Research (AFAR) and the Wind Engineering, Energy and Environment Dome (WindEEE Dome) in the Advanced Manufacturing Park.
Combined, these four facilities host more than 20 researchers from several faculties, including Engineering, Science, Social Science and Ivey Business School. Western is the only institution in Canada currently offering a graduate program in wind engineering.
Part of Kopp’s work, for a number of years, has been completing damage surveys following tornadoes. While there can be massive damage to a wide swath of structures, Kopp quantifies wind speeds at the time – data Environment Canada uses when reporting damage assessments.
“When you hear reports on the radio or TV that it was an F2 tornado or winds were clocked at 200 kph, our works has gone into that,” Kopp said.
Kopp will continue his work at the Boundary Layer Wind Tunnel where, next year, he will assist on a Carelton University-led Natural Sciences and Engineering Research Council of Canada (NSERC) project exploring how gas flares emit contaminants into the atmosphere.
Flaring is the burning of natural gas that cannot be processed or sold. The practice disposes of the gas while releasing emissions into the atmosphere. The practice has become so commonplace that the Intergovernmental Panel on Climate Change, established by the United Nations Environment Program, has targeted it for study.
“There are models for the emission of that but they are all based on the wind not having any turbulence and, of course, the wind has turbulence,” said Kopp, who will use four-inch diameter flares shooting up to 10-foot flames inside the wind tunnel. “We think turbulence in the wind will double the emission from a gas flare, so it’s a huge effect. It’s not just carbon dioxide. What happens is the turbulence strips off the gas and it doesn’t burn and that goes in the atmosphere and that’s even worse.”