Secondary Dwelling Units

Secondary Dwelling Units Policies provide residents a simplified application process for the addition of a secondary dwelling unit in their homes or in an accessory structure on the property.

Residents applying for secondary dwelling units are no longer required to apply for a re-zoning of their property. However, secondary dwelling units must still comply with Building and Fire Codes, and Zoning and Property Standards By-laws. They must also go through the necessary building permit application and approval processes.

What is a Secondary Dwelling Unit?

A secondary dwelling unit is a self-contained unit consisting of a room or rooms in a single detached, semi-detached, row house dwelling, street townhouse, or accessory buildings. The secondary dwelling unit may be contained in any part of the house, not just the basement. It may also be contained within an addition to the existing dwelling or within an accessory structure. The secondary unit must have a separate means of entry, a kitchen, a bathroom and sleeping facilities.

The following policies apply to secondary dwelling units  (Details can be found in the Secondary Dwelling Unit Guide at the link below)::

  • A maximum of one secondary dwelling unit is permitted within the primary dwelling and one secondary dwelling unit is permitted within an accessory structure on a lot.
  • Adequate servicing must be available to the property (infrastructure).
  • Must not be located on, or adjacent to, hazard lands.
  • Must not cause alterations to the main building exterior that would change the character of the existing neighbourhood. Street facing doors are not permitted on secondary dwelling units that are contained as part of the house.
  • Must meet all applicable requirements of the Zoning By-law, Building Code, Fire Code and Property Standards By-law.
  • Only permitted in detached, semi-detached, street townhouses and row houses, and ancillary structures.
  • Purpose-built secondary dwelling units in the view form of a semi-detached dwelling must be a minimum of 10% smaller than the main unit.
  • One parking space is required per unit.  A parking space for a secondary dwelling unit may be a tandem parking space.


Secondary Dwelling Unit Guide (PDF)

Application Checklist for Secondary Dwelling Units (PDF)

Application Form for Creation of a Secondary Dwelling Unit (PDF)

Application Form to Register a Secondary Dwelling Unit (P

Secondary Dwelling Units Registry (Excel Format)

Secondary Dwelling Units (Online Mapping)


The Development Dashboard tracks residential, industrial, commercial and institutional development in the City, including secondary dwelling units.