Canadian Contractor

Steve Payne   

Engineer charged as Algo Mall collapse enquiry continues

Canadian Contractor Environment Vehicle

For 30 years, water from the parking lot on the roof of the mall seeped into the steel structure underlying the hollow concrete slabs. A continuous rubberized asphalt membrane, that would have protected the steel, had been considered too expensive.

The public enquiry into the Algo Mall collapse at Elliot Lake, ON, is about to enter its third month. Meanwhile, the Ontario Ministry of Labour has laid charges against an engineer who inspected the mall – and then wrote a report declaring it structurally sound – just two months before part of its roof collapsed, killing two women and injuring 20 people, June 23 last year.

The engineer, Robert Wood, of M.R. Wright & Associates, Sault Ste-Marie, ON (the firm has now been shut down) faces charges under the province’s Health & Safety laws for “endangering a worker” by “providing negligent advice,” the Ministry said.

Forensic engineering firm NORR has testified at the enquiry that years of water and road salt from the parking lot located on the top of the mall had corroded the steel structure underneath the hollow concrete panels that comprised the roof.

The roof was built without an adequate waterproofing system. The option of a continuous rubberized asphalt membrane that would have averted the corrosion that led to the tragedy was, according to testimony at the enquiry, rejected because of both cost and weight considerations (the roof was already heavier than the structure could safely support). Instead, an ad hoc system of dealing with individual leaks as they occurred became the norm. These leaks started showing up almost immediately upon completion of the structure and were a matter of public record, as were the obvious potential structural implications, for the next three decades. But no action was ever taken to remedy the serious engineering and construction mistakes.


Eventually, a weld failed, owing to the corrosion that, the public enquiry has been told, was caused by so much salt water entering the steel structure that it was equivalent to “a marine environment.” In the ensuing catastrophic failure of the roof structure (a video simulation of the event, shown at the enquiry, shows a passing vehicle on the rooftop parking lot triggering the collapse) hundreds of tons of concrete slabs fell to the next level of the mall.


Stories continue below

Print this page

Related Stories

1 Comment » for Engineer charged as Algo Mall collapse enquiry continues
  1. If the roof was already too heavy, why was the building permit issued? Why was the design not altered to suit the weight of the roof with a membrane. Sorry but this sounds like a comedy of errors from day one. As I said when interviewed on CBC News, concrete, rebar, steel and salt don’t mix.

Leave a Reply

Your email address will not be published. Required fields are marked *


This site uses Akismet to reduce spam. Learn how your comment data is processed.