Union Certification in Ontario’s Construction Industry: A Primer

August 6, 2019 | Greg Bush, Damien Buntsma, Michael Cleveland

Union certification is the procedure by which a union gains the right to exclusively represent a group of employees in negotiations with an employer. The Labour Relations Act, 1995, S.O. 1995, c.1, Sched. A (“LRA”) governs the union certification process in Ontario.

In most industries, after a union submits signed union cards showing that 40% of employees in a proposed bargaining unit support unionization, the Ontario Labour Relations Board (the “Board”) will order a secret ballot vote. If a majority (50% plus one vote) of ballots cast are in favour of unionization, the Board will certify the union as the employees’ exclusive bargaining agent.

In Ontario’s construction industry, however, union certification may occur without a vote taking place.  Instead, unionization can be achieved by way of “card-check certification”; if a union is able to show that more than 55% of the employees in the bargaining unit have signed union cards in support of unionization, the Board will typically certify the union without a vote. Where a union can only show between 40% and 55% support by way of signed union cards, the Board will order a secret ballot vote in which the union must attain 50% plus one vote in order to be certified.

Recent amendments to the LRA made by the Making Ontario Open for Business Act, 2018 eliminated card-check certification for unions in several industries, leaving the construction industry as the only industry in Ontario to retain this process.

Employers should be aware that the relevant set of employees for the purpose of meeting the 55% threshold for card-check certification are generally those who were performing bargaining unit work on the day the certification application was filed. Thus, the tasks a worker is performing on a given day can have a significant impact on the outcome of a certification application.

Moreover, employers must be attentive to unionization efforts in the workplace as deadlines to respond to certification applications are very short. If an employer wishes to contest a union’s description of a proposed bargaining unit, it has only two business days to respond. Given the short timelines involved, and the fact that unionization can significantly impact the viability of a construction employer’s operations, it is crucial that employers remain aware of developments in the workplace and seek out guidance from expert legal counsel on a proactive basis.


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