Quebec will spend $870 million for a new roof at Montreal’s Olympic Stadium, a facility that has been a painful topic for the province for many decades because of its massive cost overruns and the roof that's unable to withstand the Canadian winter.

The Olympic Stadium, completed in 1976 for the Montreal Summer Olympics, is one of the most iconic structures in North America but it has also proven to be one of the most costly and inefficient stadiums, according to various studies. The stadium's current roof has holes in it, making the stadium unusable whenever it snows.

The issues with the stadium reflect the negative financial legacies sometime left behind around the world when a city hosts the Olympics, often building grand structures that are more elaborate than they might otherwise be to impress on the world stage and making further investments that can mean outright initial losses or lingering expenses. Los Angeles was aiming for a 'no build' Olympics in 2028 to avoid those problems after the Tokyo Olympics and Sochi Winter Games had multiple cost overruns and London's 2012 Games generated by one study an estimated $5 billion but at a cost of $18 billion.

Caroline Proulx, provincial minister of tourism, announced that the Pomerleau and Canam construction firms have been hired to remove the damaged roof, replace the technical ring at the top of the stadium that holds the roof in place, and install a new roof that will not be retractable. Work is set to begin this summer and is expected to take four years.

The new roof is expected to generate economic benefits valued at about $1.5 billion over 10 years because of more events being held at the stadium, according to a statement issued by the Quebec government. The government did not disclose how it plans to fund the roof replacement project.

The stadium in its current state must remain empty whenever three centimeters of snow or more are expected to fall, effectively making it unusable for the entire winter. The stadium's current Teflon roof, installed in 1998, contains about 20,000 tears, Proulx said in December.

The projected cost of the roof replacement rose significantly after engineers determined last July that the 500-metre oval-shaped concrete technical ring that supports the roof also needs to be replaced. The Quebec provincial government initially promised to replace the roof in 2017 at a cost of $250 million but the repair project never proceeded.

The Olympic Stadium sits within Olympic Park, which is expected to be home to a new seven-floor hotel on the only section of the park that is not owned by the Quebec provincial government.

"The stadium grounds will be inaccessible during the construction work. That said, all the other facilities in the Olympic Park will continue to offer a varied program, including the various festivals, outdoor activities, trails and promenades, the sports centre and the stadium tower, scheduled to reopen in 2026," Olympic Park representative Cédric Essiminy told CoStar News in an email.

Desjardins Group leases 170,000 square feet of office space in the stadium tower where about 1,200 employees work. Those offices will remain open throughout the construction work, according to Essiminy.

Some in Quebec have argued the Olympic Stadium that has long been plagued by roofing issues should be demolished. However, demolition could cost up to $1 billion, according to studies, as the facility would have to be dismantled piecemeal because imploding the structure could cause damage to the metro tunnels underneath.

The Olympic Stadium could be demolished at a much lower cost than the $1 billion estimate, some argue. “I don’t think it would cost that much,” Mitchell Rose, president of Quebec Demo, a Montreal demolition firm, said in an interview, citing the much-lower price tag of the recent $400-million Champlain Bridge demolition, a highly complex project executed over the fast-flowing St. Lawrence River.

Rose said that his demolition firm is too small to undertake a demolition job as large as the Olympic Stadium but he expressed a commonly heard frustration toward the stadium.

“The Olympic Stadium is a beautiful, world-renowned structure but it’s just not practical. We have to replace the roof every 10 years, it makes no sense,” said Rose.

However, the Quebec provincial tourism department noted the stadium can generate significant income when operational. Tourism minister Proulx said the current state of the stadium, which has a capacity of 56,000 spectators and is the biggest stadium in Quebec, has cost the local economy millions of dollars in potential revenue. She estimated the province missed out on $350 million in revenue due to its inability to host a series of Taylor Swift concerts.

The Olympic Stadium was formerly the home stadium for the Montreal Expos baseball team, the Montreal Alouettes of the Canadian Football League and the Montreal Impact team of Major League Soccer. It also previously hosted the Montreal Auto Show, but the show moved to the Palais de Congres conference centre in downtown Montreal. The stadium currently hosts about 30 events annually, according to the press release.

The building was originally supposed to be completed in 1972 but constant labor disruptions led to it being completed barely in time for the 1976 Summer Olympics. Neither the tower nor retractable roof in the original design were in place at the time. The building ultimately cost $1.1 billion, far more than the $134 million initial projected cost.

In 1985, provincial authorities authorized funding for a retractable roof to be paid for by dedicated tobacco tax. A bright orange retractable roof was completed in April 1987 but was rarely opened.

In January 1992, a section of the roof collapsed, dumping snow and ice onto workers setting up the auto show, leading to its cancellation. The roof was modified with pipes containing heated water to allow snow to melt. The new roof was ripped by a windstorm in June 1992 and management chose to keep the roof on at all times. The damaged roof was removed in May 1998 and replaced later that year with a $26 million blue roof that was not retractable.

In 2004, the Olympic Installations Board signed a deal to put a permanent steel roof atop the structure but the provincial government did not approve the $300 million in funding required to complete the project. Damage to the roof in 2009 led the Olympic Installations Board to order the facility remain closed if three centimeters or more of snow were expected to fall, leaving it effectively unusable in winter.

In 2013, engineers issued a report discussing the potential cost of demolishing the stadium, noting that demolition would be extremely costly due to logistical issues. In 2017, the Quebec government approved a new roof at the price of about $250 million but did not proceed with any work. The current CAQ government led by Premier Francois Legault came into power in 2018.