Canada’s building codes don’t focus on tornadoes — even though we see dozens a year | CBC News

Fran Ferguson said she often doesn’t take severe weather warnings very seriously, but something – maybe a feeling or the way the wind was blowing on Thursday, July 15 – made this different.

When the Barrie, Ontario resident received a notification on her phone, she began preparing her basement, storing her purse, essential medication, and a bed for her dog where she was safe.

Ten minutes later, the EF-2 tornado struck.

“Suddenly the power was off. I looked up and heard what was like a freight train. I just grabbed the dog and ran. ”

It’s a sadly familiar story that repeated itself across Canada this summer. The country records an average of more tornadoes than any other in the world, with the exception of the United States, at around 60 per year – although weather forecasters estimate there are more that go undetected.

Yet the National Building Code of Canada places little emphasis on requirements for protection against upwelling – the types of winds that are generated by tornadoes.

While it’s hard to say whether climate change could contribute to an increase in tornadoes in Canada, our growing population has resulted in a larger human footprint, which means there are more buildings where there used to be forests or farmland – and more Opportunities for tornadoes that can cause damage to human structures.

At first, the worst damage to Fran Ferguson’s roof appeared to be a hole about a foot in diameter, pictured to the right. She was surprised to learn that her entire roof needed replacing. (Submitted by Fran Ferguson)

“We were lucky that there weren’t many deaths from tornadoes in Canada. But I think we don’t want to rely on luck, we want to rely on technology,” said Greg Kopp. ImpactWX Chair in Severe Storms and Senior Researcher for the Northern Tornadoes Project based at Western University in London, Ontario.

For years, Kopp has been campaigning for hurricane tapes to be prescribed by Canadian building regulations. The small metal brackets, also known as hurricane clips, can help prevent a roof from flying down by securing each truss to the top of a wall.

“Adding hurricane tape costs less than a few hundred dollars per home, so I think it’s an inexpensive move,” he said.

Hurricane belts are effective up to EF-2 wind loads, and Kopp said the vast majority of tornadoes in North America are EF-2 or less.

CLOCK | How tornado damage analysis helps improve building codes:

Learn how tornado damage analysis helps improve building codes and prevent future disasters 1:25

Ferguson said she would consider it if she ever had a new house built.

She managed to get out of the tornado unscathed and when she went outside to check her house she said it didn’t seem that bad except for some water damage inside and a hole in the roof that needed mending .

She was surprised to learn that her three-year-old roof had to be completely replaced because the tar paper – a weatherproof layer between plywood and shingles – had been lifted by the wind and the roof had burst open in places.

So it might be a good idea to change the building codes, Ferguson said.

“If it can even save a few people, it’s worth it. To me, it’s worth it. Anything we can do to make our homes safer, we should do.”

Fran Ferguson said the tornado hit the hardest four doors from her home in Barrie, Ontario. She is glad the damage to her home wasn’t worse. (Submitted by Fran Ferguson)

City Council urges Ontario to update codes

The EF-2 tornado that hit Barrie last week hit wind speeds of 210 km / h maximum and rendered about 60 houses uninhabitable while also displacing more than 100 people.

It was one of five tornadoes – all in the EF-2 range – that landed in southern Ontario on July 15.

On a single day the month before, four tornadoes landed in southern Quebec in an hour and fifteen minutes, killing one man in Mascouche, Que.

Barrie councilor Natalie Harris hopes more deaths could be prevented in the future if building codes are updated.

After witnessing the Barrie tornado first hand, she began to research whether the damage to her city could have been prevented. So she finally spoke to Kopp and joined his call to require hurricane belts.

Harris was visiting her 15-year-old son at her ex-husband’s house when the tornado struck. The couple made it to the basement just in time. When they returned to assess the damage, Harris found that the roof was missing.

“I looked up the stairs and saw the sky,” she said. “My son, if he was upstairs in his room I don’t even want to think about what would have happened.”

Now Harris has published its own call for Ontario to update its building codes to include requirements for high wind protection.

She has scheduled a meeting with stakeholders and members of the provincial parliament next week and plans to propose to Barrie city council in August. Their motion calls on the city to propose changes to Ontario’s building codes while providing financial incentives to encourage homeowners rebuilding after the tornado to include strict windbreak measures.

Harris has already received support from fellow councilors and Barrie Mayor Jeff Lehman, who described the plan as “an inexpensive increase in construction that could help mitigate damage from certain storms.”

For Harris, it’s simple: “It could prevent future deaths.”

Recommend, don’t hire, says the association

The idea of ​​encouraging the use of hurricane tape in new buildings has also been considered by the Canadian Home Builders’ Association (CHBA), although the organization rejects the idea of ​​making these additional measures mandatory.

“In our view, before building codes can begin, we need to better understand where tornadoes are likely to hit because the changes that would need to be made to a low building like a house are quite substantial.” says Frank Lohmann, Director of Building Sciences at CHBA.

The Barrie tornado left more than 100 residents whose homes are no longer safe. (Laura Clementson / CBC)

“When we start applying [these changes] Anywhere, this would increase housing costs in all areas and it may not be necessary in all areas. “

He said a better way could be to first create a set of recommended tornado measures that could be applied voluntarily based on the location of the building and other factors such as insurance incentives.

The association is currently involved in the development of best practice standards for the construction of low-rise buildings that could come out of an EF2 tornado relatively undamaged, said Lohmann. The standards are expected to be released in 2022 and used by home builders, designers and contractors across Canada.

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