Secondary Suites

The term “secondary suite” is generally used to describe a self-contained dwelling unit with its own kitchen and bathroom, which is separate from the principal dwelling in a house. It can be located either within the principal dwelling or in an accessory building on the same lot as the principal dwelling. These units are also known as “accessory apartments” and “in-law suites.” Basement apartments are the most common type. Aside from being affordable to renters, they also provide income and extra security for the home owner who has more space than is needed, and make entering the housing market easier for first-time buyers who may use the rental income to offset their mortgage costs.
Secondary suites are an affordable housing option that meets the needs of many people, including members of an extended family, singles, seniors and people with low or fixed incomes. Since they are usually constructed inside existing buildings, they help optimize the use of existing housing stock and infrastructure, and re-populate neighbourhoods with declining populations.
What Regulations Apply to Secondary Suites?
Whether you intend to renovate an existing secondary suite or add a new one, the secondary dwelling unit must conform to all zoning, building and fire code requirements.
Municipal Zoning by-laws
Most Canadian municipalities have zoning by-laws that regulate, among other things, the type, size and height of buildings, what they are used for, the location of parking and the number of spaces, the depth of the front, rear and side yards, and the portion of the property area that the building can occupy. Zoning determines where factories, businesses, shopping centres, schools, single-family houses and apartment buildings may be located. It also determines whether a house can contain a secondary suite.
Most cities contain several different residential zones, each permitting a maximum intensity or density of dwellings. For example, an R1 zone usually permits single-family residences; an R4 zone duplexes and semi-detached houses, row dwellings and apartments up to 4 storeys; and an R7 zone high-rise apartments. Unless expressly permitted, you would not be allowed to build a secondary suite in a zone that permits only single-family houses.
Canada Mortgage and Housing Corporation completed a study which identifies zoning regulations in municipalities and summarizes the provisions for secondary suites. The study noted that secondary suites are permitted in the entire urban area or in certain locations in 220 of 404 municipalities. The municipalities that allow secondary suites regulate them in the following ways:
Discretionary or conditional use — Secondary suites are subject to a specific approval process identified as discretionary or conditional. This means the secondary suite may be refused.
As of right use — Secondary suites are allowed if they comply with zoning and building code regulations.
In primary dwelling — Secondary suites are allowed within a principal dwelling.
In accessory building — Secondary suites are allowed in an accessory building such as a coach house, above a detached garage or in a portable building.
For a specific occupant — Secondary suites may only be occupied by a specific occupant such as a family member, a parent of a certain age or a person with special needs.
Municipal approval or agreement — Distinct from the normal permitting process, this means that the applicant must sign an agreement, sign a declaration as to the parental link, or obtain a special occupancy permit.
Architectural integration — This requires the building containing the secondary suite to respect the surrounding buildings or the single-detached character of the property.
Time limited — The zoning identifies the secondary suite as a temporary use, sets time limits for this use, and may require that the building be returned to its original condition when the accessory apartment has been vacant for a given period of time.
Size limited — The zoning limits the size of the secondary suite in relation to the primary building, limits the number of rooms, or determines a minimum lot size for a secondary suite to be permitted.
In a specific zone — Secondary suites are permitted in specific zones and prohibited in others.
In a specific building type — Secondary suites are permitted only in specific types of buildings such as single-detached residences.
In a specific zone and building type — Secondary suites are permitted only in a specific type of building in a specific zone.
If you are considering building or renovating a secondary suite in your house or on your property, you should first consult one of your city’s Development Information Officers. They will tell you whether a secondary suite is permitted on your property, whether additional parking is required, where the entrance and windows can be located, how large the apartment can be and how many bedrooms it may contain. Some municipalities only permit you to rent a secondary suite to a family member. Others may or may not allow the secondary suite doorway to be visible from the street. If you were to build a secondary suite in violation of your zoning requirements, you could be forced to make it comply or to remove it altogether.