Provincial building code standards for homes do not include ‘resisting loads’ created by tornadoes: memo to council

The July 15 tornado (not pictured here) created loads on structures that are in excess of what they are intended to withstand: staff memo. Photo by Nikolas Noonan on Unsplash

If building standards that may enable homes to survive tornados are to emerge, it will be through changes to the Ontario Building Code (OBC), Michael Janotta, Barrie’s chief building official/manager of building, writes in a memo to council.
Currently, those standards aren’t in the code.
“The (code) defines the minimum standards for building construction. These minimum standards do not include resisting loads created by the effects of a tornado. The (July 15) tornado event created loads on structures that are in excess of what they are intended to withstand. There is a difference between meeting the (code), which defines minimum construction requirements, and building to be tornado resistant, which is a standard much higher than specified in the building code,” he writes.
“The OBC consists of different parts which apply to different building types based on size of building and occupancy type. Some buildings are required to be designed by professional engineers for the loads specified in the code. These are performance standards which are applied to engineered buildings. Other buildings are not required to be designed by professional engineers as there are prescriptive requirements which are in lieu of engineered design … houses fall into the category of buildings that are built based on prescriptive standards. As such, most houses will be built with no specific consideration of wind loading.” 
As for the City’s role in the process, Janotta writes that the municipality meets its obligations under the code, reflecting best industry practises.
“However, more stringent building requirements cannot be legally enforced until modifications are made to the Ontario Building Code to mandate different construction techniques.”
The EF2 tornado that touched down in south-east Barrie reached winds up to 210 k-ph, damaging hundreds of homes and small businesses. As of July 30, 85 engineering reports had been received and reviewed; 51 apply to houses with unsafe orders, and 34 apply to houses without unsafe orders, but may still require a building permit for repair.
Of the original 70 unsafe orders, 39 houses are permitted entry by the occupants and/or contractor, 12 houses are deemed safe for continuous occupancy, six building permit applications have been issued for repair of existing houses, and two demolition permits have been issued to homes that will need to be rebuilt.
“It is anticipated that staff will be involved with work on the tornado affected houses for a period of three months in assessing reports, reviewing drawings, and issuing permits and for a period of 12 to 16 months in inspecting the reconstruction,” reads the memo. “In addition to the work of the Building Department, the Operations Department continues with clean up assistance in the affected area.”

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