Basement Apartments (Accessory Apartments)

In the Town of Milton, accessory apartments are self-contained dwelling units created by converting part an existing dwelling. They can also be constructed as part of a new dwelling.

Accessory apartments are also sometimes referred to as secondary suites, secondary units, basement apartments and accessory dwellings.

Only one accessory apartment is permitted in a dwelling unit. All accessory apartments, new and existing, require a building permit and must comply with any applicable laws and standards.  This includes, the Building Code, the Fire Code, property standards by-laws, and the Town of Milton Zoning By-law.   

Building Permit Application Guide for Accessory Apartments

 Zoning Requirements (By-law 016-2014)

All accessory apartments must meet Comprehensive Zoning By-law 016-2014 requirements:
  • An accessory apartment is permitted in a single detached dwelling only;
  • Only one accessory apartment unit is permitted per lot, and must be located within the main dwelling unit;
  • A minimum of one parking space per accessory apartment unit must be provided, in addition to the required parking for the main dwelling unit *;
  • The dwelling must be on full municipal water and wastewater services; and,
  • The accessory apartment must not exceed a maximum size of 85 m2 (915 square feet).

*Parking spaces must meet the minimum dimensions required by the Zoning By-law.  Required parking spaces can be accommodated on a driveway, in a garage, or a combination thereof. 

 Rates and Fees

 Changes to the Planning Act

Various sections of the Planning Act have been amended to facilitate the creation of second units.  For more information relating to these changes, visit the Ontario Ministry of Municipal Affairs and Housing for details on Secondary Units.

All accessory apartments, new and existing, require a building permit.

Before You Begin

Before proceeding with the construction of a new accessory apartment, please contact Zoning at 905-878-7252, ext. 2329 for clarification and to obtain a building permit.