What is the minimum size for a legal basement bachelor apartment in Ottawa?

For a legal basement bachelor apartment in Ottawa, the minimum size is 28 square meters (approximately 301 square feet), as specified by the Ontario Building Code and enforced by the City of Ottawa's zoning bylaws.

This 28m² minimum applies specifically to bachelor units and represents the total floor area of the dwelling unit, not including shared spaces like laundry rooms or storage areas that serve the primary residence. The measurement includes the main living area, kitchen space, bathroom, and any closets within the unit. This size requirement ensures the unit provides adequate living space while meeting health and safety standards.

Beyond just square footage, your basement bachelor apartment must meet several other critical requirements to be considered legal in Ottawa. The unit needs a separate entrance (either exterior or through a common hallway), adequate ceiling height (minimum 6'5" in most areas, 6'1" in bathrooms), proper egress windows for emergency escape, and fire separation with a 45-minute rating between the basement unit and the main house. The space must also have natural light in the main living area and proper ventilation.

Ottawa's R4 zoning regulations govern most residential areas where secondary suites are permitted, though you'll need to verify your specific property's zoning designation. The city requires building permits for basement apartment conversions, and the process typically involves structural, electrical, plumbing, and HVAC inspections to ensure code compliance. Many older Ottawa homes require significant mechanical upgrades to support a separate dwelling unit, including separate heating controls and upgraded electrical panels.

Professional guidance is essential for basement apartment conversions because of the complex interplay between building codes, zoning requirements, and mechanical systems. DIY approaches often result in failed inspections and costly rework, particularly with fire separation requirements and HVAC modifications. The permit process typically takes 4-8 weeks, with total project timelines ranging from 3-6 months depending on the scope of work required.

Your next step should be confirming your property's zoning eligibility through the City of Ottawa's online portal at ottawa.ca/building, followed by a professional assessment of your basement's potential for conversion. For a comprehensive evaluation of your basement's suitability for a legal bachelor apartment, Ottawa Basements offers free consultations that include zoning verification and preliminary design concepts.