Legal basement apartments in Ontario: what homeowners need to know

What changed with Bill 23

The More Homes Built Faster Act, 2022 (Bill 23) received Royal Assent on November 28, 2022. According to the Province's Environmental Registry notice, it allows up to three units per lot "as-of-right" in many existing residential areas. That means up to three units in the main house, or up to two in the house and one in a building such as a garage.

"As-of-right" means you do not need a rezoning just to add the unit. It does not mean you can skip a building permit or the Building Code.

Where the three-unit rule applies

The provincial permission applies to land where residential uses are allowed in settlement areas with full municipal water and sewage services. Many homes in Lindsay, Port Perry, Peterborough and Durham's urban areas fit that description.

Many rural properties in Kawartha Lakes and Scugog are on wells and septic systems. The provincial rule may not apply there, but local zoning might still allow an additional unit. The Province's guide to adding a second unit also says a septic system must have the capacity to handle the extra sewage, or it will need an upgrade. Ask your planning department first.

Zoning, parking and development charges

Local zoning still covers things like entrances, unit size limits and setbacks. Under the Bill 23 changes described in the Environmental Registry notice, municipalities cannot require more than one parking space per additional unit, and development charges do not apply to these second and third units in many cases.

Check your property with the municipal planning department before you design anything. Some municipalities also have rental licensing rules. For example, Oshawa's basement guide notes that a building permit is not approval under the City's licensing by-law or the Ontario Fire Code.

You need a building permit

The Province's second unit guide is direct: to add a second unit in your house, you will need a building permit. Inspectors review work at several stages, including framing, insulation and plumbing.

The guide recommends hiring a qualified professional such as an architect, professional engineer or a designer registered with the Ontario government to prepare the drawings and help with approvals.

Key Building Code items for a basement suite

The provincial guide was written for houses more than five years old, which get some flexibility under Part 11 of the Building Code. Newer houses generally must meet new-construction rules. The main items it covers include:

• Fire separation: a 30-minute fire separation between units and between units and common areas, which the guide says can be reduced to 15 minutes if the entire house has interconnected smoke alarms
• Exits: a separate exit is preferable; a shared exit needs fire separation and interconnected smoke alarms, and some layouts need an escape window
• Smoke and carbon monoxide alarms in the right locations
• Minimum ceiling heights, room sizes and window areas
• A special duct smoke detector that shuts down the furnace if both units share one heating system
• Separate water shut-off valves, and possibly a backwater valve
• Kitchen and bathroom ventilation

Electrical work for a second unit

The provincial guide says you will need a separate electrical permit for the second unit, and the Electrical Safety Authority will inspect it. The ESA says anyone you hire to do electrical work in your home must, by law, be a Licensed Electrical Contractor.

Already have a basement apartment?

Existing two-unit houses fall under the Ontario Fire Code. Section 9.8 of the Fire Code's retrofit part applies to detached, semi-detached and row houses with two residential units, where the building is three storeys or less, no more than 600 square metres in building area, and one unit is above the other or the units share an interior exit. It sets minimum requirements for fire separations, exits, alarms and related protection.

Local fire departments enforce the Fire Code and can inspect. If you bought a house with a suite, or you are not sure an existing unit was ever approved, contact your building and fire departments. A house with three units may fall under different rules, so ask which ones apply.

Every suite is project-specific

Two houses on the same street can have very different paths to a legal suite. Ceiling height, the existing stairs, window sizes, the furnace, the electrical panel and the lot all matter. Some basements need only modest changes. Others need a new entrance, larger windows or major mechanical work.

That is why a feasibility review comes first. You want to know what the suite will need before you commit to a design or budget.

A sensible order of steps

Planning a suite goes more smoothly when decisions happen in the right order. A typical path looks like this:

• Confirm zoning, servicing and any licensing rules with your municipality
• Have the space reviewed for ceiling height, exits, windows, stairs and mechanical systems
• Prepare drawings with a qualified designer, architect or engineer
• Apply for the building permit and file the ESA notification for electrical work
• Build with inspections at each required stage
• Keep your permit, inspection records and ESA documents for your files

Talk to Oakridge about a basement suite

Oakridge treats every suite as a project-specific review. At a free site meeting we look at your layout, access and services and talk through what approvals are likely needed before anything is priced as a compliant suite. Call 289-731-2086 or request a free site meeting online.