Converting part of our house for family in Ontario — realized I had the terminology wrong and it matters more than I expected
We're in the middle of looking at converting part of our home for family to move into, and partway through the research I realized I had the language wrong.
I'd been saying "in-law suite" because that's just how everyone talks about it. But once we started looking into permits, insurance, fire separation, and egress, the difference between "in-law suite" and "secondary suite" stopped being just a terminology thing.
What I didn't realize going in: if the space is genuinely self-contained — its own sleeping area, bathroom, cooking setup, separate entrance — the building department and your insurer may not care what you call it. They may treat it as a secondary suite or additional residential unit regardless of your intent. That was a shift in how we were thinking about the whole project.
The insurance side surprised me the most. We assumed that because family was moving in and no rent was involved, the policy would basically be unchanged. Then I started reading and realized I had no idea what the actual answer was. We're planning to ask very specific questions before doing anything permanent — things like whether a second kitchen changes the risk classification, whether a separate entrance matters to them, what happens if the unit is ever rented out, and whether an undisclosed self-contained unit could affect a claim.
The fire and building code side also turned out to be a bigger scope than we expected. The stuff that looks cosmetic at first — fire separation, interconnected smoke and CO alarms, egress windows, HVAC — can become the real project once you understand what's actually required in your municipality.
I know the answer depends on the city, the house age, and what the local building department says. I'm not looking for legal advice. Just the practical experience from people who have gone through this in Ontario.
If you converted space for parents, adult kids, or extended family — what caught you off guard? Did the insurance conversation end up being harder than permits? Did your building department actually distinguish between "in-law suite" and "secondary suite," or did it come down to whether the unit was self-contained?
And if you could go back, what would you have asked before starting any work?