Real Estate Law Toronto: Legal Non-Conforming Uses

Legal Non-Conforming Uses

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A legal non-conforming use occurs when the use of one’s land, building or structure is not permitted by the current zoning by-law, but was permitted by a previous by-law. Pursuant to section 34(9) of the Planning Act, no zoning by-law passed can be applied to prevent the continued use of a piece of land, building or structure if the land, building or structure was used lawfully for that purpose on the day the by-law was passed. The land, building or structure must be continuously used for that purpose.

The Relevancy of Legal Non-Conforming Uses

Section 34(9) of the Planning Act applies to prevent new municipal zoning by-laws from interfering with the continued legal use of one’s land, building or structure. Without this provision, land and business owners would have less stability and would be subject to all zoning by-law changes. However, restrictions on how a land owner can alter an existing legal non-conforming use aim to reduce or eliminate legal non-conforming uses in the long term.

Your municipality may require an application to formally establish a legal non-conforming use to be completed upon discovery of a non-conforming use. A non-conforming use may be discovered in a variety of circumstances, such as during a Committee of Adjustment application, when a search record request is completed or during a by-law investigation by an authority.

Applications to the Committee of Adjustment

If you desire to expand or otherwise alter a legal non-conforming use, you must first bring an application to the Committee of Adjustment (the “Committee”). Otherwise, you may be forced to remove or undo any changes made to the property in the event that the application is not approved. The legal non-conforming use must have continued until the date of the application to the Committee.

There are three main categories of applications in relation to legal non-conforming uses that can be brought to the Committee:

Enlargement or Extension of a Building or Structure

The Committee may permit the enlargement or extension of a building or structure where the use of the building or structure is a legal non-conforming use. In order to be approved, the enlargement or extension must not go beyond the limits of the land, the building or structure must be an existing building or structure, and the applicant must own the lands. Even if all of these requirements are met, the Committee may not approve the application because it will also consider the impact an enlargement or extension might have on the surrounding neighbourhood and the public interest.

For example, in Sims et al. v Daschko, 1975 CarswellOnt 1185 (OMB), the Ontario Municipal Board (the “Board”) set aside the decision of the Committee to grant an extension of a bakery which existed as a legal non-conforming use within a residential neighbourhood. The decision was set aside because of the adverse impact the extension would have on the neighbouring properties, such as a reduction in sunlight exposure.

Similar Purpose

The Committee may permit the use of a lot of land, building or structure for a purpose that is similar to its historical use before the by-law was passed. Similarity will be assessed in terms of planning purposes, such as the physical, economic and social impacts of the use.

For example, in Frank Sciabbarrasi Holding Ltd. v Milton (Town), 2001 CarswellOnt 5692 (OMB), the Board upheld a decision of the Committee to deny a similar use application to convert a private picnic event location to a public driving range. The Committee stated that the uses were not similar because they varied in location on the property, hours of operation and nature of activities.

More Compatible Purpose

The Committee may permit the use of one’s land, building or structure for a purpose that is more compatible with the uses permitted by the current by-law than the purpose it was used for historically. The Committee will consider the goals or intentions of the Official Plan and zoning by-laws in determining if a use is more compatible.

For example, in Sault Ste. Marie (City) v MacWilliams, 1974 CarswellOnt 1236 (OMB), the Board set aside a decision of the Committee to allow the legal non-conforming use of a building as a grocery store to be varied for use as a laundromat. The decision was set aside because it was determined that a laundromat would produce increased traffic compared to that of the grocery store, contrary to the goal outlined in the Official Plan to reduce traffic in the residential neighbourhood.


Currently, the Planning Act permits lawfully existing uses of one’s land, building or structure to continue despite changes to the zoning by-laws in the area, providing some security to land and business owners. Strict rules regarding applications to enlarge or vary the use of the land, building or structure aim to eliminate legal non-conforming uses in the long term. Applications or appeals regarding legal non-conforming uses before the Committee or the Board can be complicated matters, often requiring expert evidence (See our article “Land Use Planning Evidence: The Basis for your Municipal Appeal” for more information). Municipal lawyers can assist with building the strongest application or appeal before the Committee or Board to protect your land or business investment.

Please contact Michael Paiva for more information about legal non-conforming uses, or if you require assistance with a Committee of Adjustment application or appeal.