How-To Plan a Secondary Suite

Building a secondary suite can be a rewarding way to generate rental income or accommodate extended family. A secondary suite, commonly known as a basement apartment, in-law suite, additional dwelling unit (ADU), or additional residential unit (ARU) must meet specific legal and safety standards to ensure it’s a livable space. If you’re considering this type of renovation, it’s important to follow all necessary steps to ensure compliance with local regulations, including obtaining permits and meeting minimum building requirements.

Obtain a Permit

The first step in building a secondary suite is to check that the zoning can be met, and obtain the necessary permits. Any construction or renovation project that alters the structure of a building, including adding a secondary suite, requires a building permit (see ARU permit). The City of Kingston has specific zoning bylaws that determine where secondary suites can be built and what is required for them to be legal for parking, and access to entrances from the street. You'll need to submit a detailed plot plan for approval of the zoning requirements, and floor plans of the  suite showing how certain safety standards and building code requirements, including fire separation, ventilation, and accessibility will be met. Ensuring that your renovation complies with these regulations helps you avoid fines or complications later on.

Minimum Area Requirements

In addition to obtaining the necessary permits, there are minimum requirements for the construction of a secondary suite. For instance, the gross floor area of a secondary suite can be equal to or less than that of the principal dwelling depending on the zoning requirements. The gross floor area includes the total area of each floor, whether above or below grade, as well as finished attic space. Measurements are taken from the outside of the exterior walls or between the exterior walls and the center line of party walls dividing the building from another.   There are also minimum room sizes and window sizes that must be calculated to meet the building code requirements.

Always consult with local authorities for the most current regulations to avoid any costly mistakes during construction.

Responsibilities of a Landlord

As a landlord, you are responsible for adhering to the Residential Tenancies Act, which governs landlord-tenant relationships in Ontario. This includes providing a safe and habitable environment for your tenants, addressing maintenance issues promptly, and respecting the terms of the rental agreement. 

Additionally, owners must follow the City of Kingston's Property Standards Bylaw, which includes maintaining the property to ensure it meets acceptable standards for safety and cleanliness. This means, depending on the conditions of the lease, ensuring proper yard maintenance and snow removal are completed, and other required issues outside of the lease such as addressing any issues that could affect the tenant’s health or well-being.

Building a secondary suite requires careful planning, adherence to local regulations, and a strong understanding of your responsibilities as a landlord. By obtaining the necessary permits, meeting building requirements, and fulfilling landlord duties, you can create a safe, comfortable space for tenants and a valuable asset for your property. Taking the time to follow the correct procedures will help you avoid issues down the road and ensure your secondary suite project is a success.

Interested in constructing a secondary suite in your home? Book a consultation to discuss our design services.