Duplex Conversion – Ontario Investors April 2025

2 Unit Conversions – Key Design Triggers to Watch

‘‘Dreaming of splitting your home into a cash flowing assets ?’’

Converting to two legal units triggers serious code requirements. Here are the top design checkboxes you can’t skip:

Fire Safety :

Ontario law requires a 30–45 minute fire-rated wall/ceiling between duplex units, including any shared stairs or hallways. Install self-closing fire doors on any inter-unit door to contain a blaze." Add at the end, "Also, don’t forget that you need sound insulation as well - rockwool & resilient channels!

Safe Exits :

Each unit needs its own exit path. If a basement or upper unit has no direct outside door, you must add an egress window (and meet the code size). A bedroom also needs an opening large enough for escape (typically ≥ 0.35 m²)", Add at the end, "AKA Egress Window, preferably installed in the bedroom space, BUT you could install in living rooms too.

Alarms & Systems :

Smoke and CO alarms are mandatory on every level and in each sleeping area. If you share the furnace, Ontario requires a smoke shut-off device in the ductwork. Also, plan for separate kitchen/bath plumbing (e.g., a backwater valve in basement drains)." Add at the end, if you have an existing finished basement, this could save you $1000s on new ceiling work if you add interconnected smoke alarms!.

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