11/02/2026
Most Ontario basements need a permit.
If your plan includes framing, new plumbing, adding a bedroom or a second unit, expect to apply. Municipal rules vary: Toronto’s exception is very narrow.
A legal basement apartment needs a permit, zoning approval, Building Code compliance and inspections. Measure ceiling height first: Ontario’s minimum is 1.95 m.
Read the full guide for the drawings checklist your city will ask for, and check with your municipal building department before you buy materials or hire a contractor. Need help preparing permit-ready drawings?