Recently, the Province of Ontario updated and introduced new policy and legislative changes related to second units. Secondary suites (a type of second unit), have been permitted since 2000, however, existing zoning regulations only permit the creation of a secondary suite five years after the primary dwelling is constructed, and do not permit secondary suites in all townhouses.

The proposed draft zoning framework responds to provincial changes in the Planning Act that support secondary suites across the province and seeks to simplify the creation of secondary suites. In the City-wide Zoning By-law 569-2013 a secondary suite is defined as:

self-contained living accommodation for an additional person or persons living together as a separate single housekeeping unit, in which both food preparation and sanitary facilities are provided for the exclusive use of the occupants of the suite, located in and subordinate to a dwelling unit.