Keith Porter, PE, PhD, chief engineer, Toronto-based Institute for Catastrophic Loss Reduction
We can design new buildings to survive disasters. But we don’t.
In December, 2021, a tornado cut a 270-kilometre path through Kentucky, killing 58 people. It led University of Florida’s David Prevatt to write a Washington Post article reminding Americans that new buildings in tornado country are not tornado proof but could have been.
We could learn similar things from Canadian tornadoes, such as the twister that struck Barrie, Ont., in July, 2021, or the September, 2018, tornadoes in the National Capital Region. Or fires, such as in Fort McMurray, Alta., in May, 2016, or Lytton, B.C., in June, 2021. Or historic floods like in British Columbia last November
Engineers know how to make new buildings resist tornadoes without making them resemble bunkers. The community of Moore, Okla., proved that. After three fatal tornadoes in 15 years, city officials decided that national building codes did not protect them so they opted to protect themselves. They enacted an ordinance making new buildings resist all but the most severe tornadoes. It added about 1 per cent to the construction cost of new houses. Despite dire warnings, researchers found no impact on home prices or development.
We could also design earthquake-resilient buildings but do not. Why? Because of a false choice between two extreme design philosophies: either build impossibly expensive earthquake-proof buildings, or accept inexpensive ones and damage short of collapse. The choice ignores the resilient middle road balancing upfront cost with long-term risk reduction.
Must we continue to accept this false dichotomy? In research for the U.S. Federal Emergency Management Agency and others, my colleagues and I found simple methods to design resilient buildings that cost 1 per cent more initially but avoid future losses many times greater.
Engineers could have used these ideas long ago. The buildings that now cost us so much in disasters could have been much more resilient and cost less in the long run.
Had it taken that middle road, the U.S. would not now be losing US$100-billion annually to disasters. That is 8 per cent of the US$1.3-trillion in annual new construction, or one month of construction cost a year of new building.
Those losses grow 6 per cent annually, 10 times faster than the population, like a credit card bill when you always buy more than you repay every month. The U.S. credit card balance of disaster liability now exceeds US$2-trillion. Canada’s buildings resemble those in the U.S., so our proportional balance probably surpasses $250-billion.
Our bill will inevitably come due in episodes of multibillion-dollar catastrophes, as in B.C. last fall.
How do we fix the problem? We could add sewer backflow valves, replace vinyl with non-combustible siding in the wildland-urban interface, and use impact-resistant asphalt shingle roofs in hail country. Catastrophe risk professionals offer long lists of sometimes-cheap, sometimes-costly solutions to problems in the buildings we already have.
Building codes created those problems, partly through their performance objectives – that is, their goals for what they will or will not require. Codes aim for safe and maximally affordable buildings, ignoring long-term ownership cost. We build cheaply but not efficiently, like building cars with the lowest sticker price but much higher maintenance costs. Or like selling coffee in single-use paper cups instead of metal travel mugs.
We could do better. Moore, Okla., did. So did Florida after Hurricane Andrew in 1992. The state leaped ahead of U.S. building codes with its own stricter code. The Insurance Institute for Business and Home Safety developed a voluntary standard called Fortified that avoids future losses and may more than pay for itself in higher resale value. Some institutional owners build new structures 50-per-cent stronger and stiffer than required because it makes good business sense.
The climate crisis is forcing major changes to Canadian codes. It offers a rare opportunity to fix our growing disaster liability at the same time, in something like three steps:
– Enact a building code objective to minimize society’s total ownership cost of new buildings. The Canadian Commission on Building and Fire Codes could formalize such a principle in the National Building Code of Canada.
– Require that at least some code-change requests be accompanied by estimates of added construction cost and benefits in terms of reduced energy use, future repair costs, improved health and life safety outcomes, and other economic effects whose monetary value can be reasonably estimated.
– Limit code committees’ freedom to reject cost-effective code-change requests.
Such changes will eventually shrink Canada’s disaster credit card balance. While it rethinks energy efficiency, Canada can rethink the false economy of “least-first-cost” construction. We can make buildings more sustainable and cost less in the long run.
With a wiser code, we can have better buildings for ourselves, our neighbours, our children and all future Canadians.
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