From Trilogy to doctrine: The growing strength of legal nonconforming rights in Ontario

Since the publication of the “Legal Nonconforming Rights Trilogy in Ontario” on May 14, 2021, Ontario’s jurisprudence around legally nonconforming uses and buildings has continued to develop with remarkable clarity and confidence.

Two new decisions—927 Wellington Street Inc. v. Ottawa and Roca Investment Holdings Inc. v. Ottawa—demonstrate not just the endurance of the Trilogy's (TDL Group, Brougham, and Fraser) principles, but their expansion into a broader and more structured body of doctrine that is reshaping land use planning across the province.

The rise of a doctrinal framework

The Trilogy laid down essential pillars: municipalities cannot extinguish legally nonconforming rights through planning instruments, and property owners retain the ability to evolve or intensify these uses, subject only to the test of undue adverse impacts.[1] We note that Fraser appeared to extend the doctrine of “acquired rights” to limit the regulatory ability of Conservation Authorities, but that is a matter still in evolution.

The two recent decisions extend and reinforce these principles in distinct but complementary ways—Wellington by affirming the adaptability of use, and Roca by confirming the resilience of use despite vacancy and disrepair.

Case update #1: 927 Wellington Street Inc. v. Ottawa — Evolution without extinction

In 927 Wellington, the Tribunal considered whether a long-standing automobile service station use could evolve into an equipment rental business for light construction and maintenance tools. The City opposed the application under s. 45(2) of the Planning Act, arguing that the use had changed and that a legally nonconforming right had been extinguished after the tenant abandoned the site.[2]

The Tribunal firmly disagreed with the City’s position. Relying on Saint-Romuald and the Trilogy, it emphasized the following:

• Intentionality matters: The owner’s prompt re-leasing efforts and intent to continue the use were enough to maintain the nonconforming status.[3]
• Evolution is not extinction: The Tribunal found that the new use—retail and leasing of light equipment—was consistent with the essence of the former garage use, representing a reasonable evolution rather than a shift in kind.[4]
• Impact governs, not semantics: There was no evidence of undue adverse impact. The change in use remained compatible with its mixed-use neighbourhood context.[5]

This decision reaffirms that property owners can adapt nonconforming uses to new economic realities—without fear of municipal or neighbourhood opposition succeeding on technical grounds.

Case update #2: Roca Investment Holdings Inc. v. Ottawa — Disrepair does not mean disqualification

In Roca, the issue was whether two century-old, legally nonconforming semi-detached dwellings could be demolished and rebuilt in slightly larger form on the same lots in the Rockcliffe Park Heritage Conservation District. The local community association challenged the application, arguing that vacancy and disrepair had extinguished the property’s legal nonconforming rights.

The Tribunal’s ruling offers a definitive doctrinal expansion:

• Vacancy is not abandonment: The Tribunal rejected the argument that disuse of the buildings—due to severe disrepair—terminated the use. It held that the buildings (the form of which had never been permitted by zoning bylaws) still represented an active, lawful use of the land under s. 34(9)(a) and s. 45(2) of the Planning Act.[6]
• Disrepair must go further to break continuity: Even uninhabitable buildings can retain legal use status if they remain visually and structurally present. Mere interior deterioration is not enough.[7]
• Fraser test governs enlargement: Applying the Fraser framework, the Tribunal found the proposed enlargements to be desirable and not resulting in undue adverse impacts, measured from the point of view of the proximate neighbourhood. Heritage and compatibility concerns were thoroughly addressed in both the design and the approval process.[8]

This case definitively affirms that physical decline does not equate to legal abandonment—a pivotal interpretation for heritage and aging structures across Ontario.

Conclusion: The doctrine takes shape

With these decisions, Ontario’s legal framework around legally nonconforming rights has matured beyond isolated victories into a cohesive doctrine:

1. Continuity is measured by intent and reasonable efforts—not rigid timelines or vacancy.[9]
2. Evolution in use is protected—so long as undue adverse impact in the proximate neighbourhood is avoided.[10]
3. Visual and structural presence matter—not mere occupancy or condition.[11]
4. Municipalities must apply Saint-Romuald and Fraser when assessing applications under s. 45(2) of the Planning Act.[12]

The principles laid down in the Trilogy are not only holding firm—they are expanding into a robust, owner-protective doctrine that commands consistency from municipal decision-makers and respect from adjudicators.

As planning laws continue to evolve in Ontario, landowners and practitioners would be well advised to internalize this case law—not as exceptions to policy, but as an enforceable part of the statutory framework itself.