Converted my Toronto basement into a legal 1-bedroom suite last year. The egress window was one of the more nerve-wracking parts - cutting through an 8-inch concrete block wall. Documenting the process here.
Why This Is Required
No egress window = no legal bedroom. Period. Under the OBC, any basement room used for sleeping must have:
- 0.35 m2 minimum unobstructed opening
- 380mm minimum opening height
- 450mm minimum opening width
- Sill max 1,000mm above finished floor
My Window Situation
The basement originally had small hopper windows that were nowhere near OBC egress dimensions. The bedroom location (furthest from the stairs) required a new window in an 8-inch concrete block wall, below grade, with a window well.
The Process
- Building permit application - took 4 weeks in Toronto
- Contractor marked the opening and cut with a diamond blade core saw
- Steel lintel installed above the opening
- New casement window (Jeld-Wen, egress-sized, vinyl) installed
- Corrugated steel window well excavated and installed outside
- 8 inches of clear stone in well base for drainage
- Waterproofing membrane applied around the exterior frame
Total Cost: $4,200
Breakdown:
- Permit: $380
- Concrete cutting + lintel: $1,400
- Window supply + install: $980
- Window well + excavation + drainage: $1,440
One Thing I Would Change
I would add a window well drain connected to the weeping tile. We had one heavy rainstorm where the well filled faster than the stone could drain. Got it fixed but it should have been in the original scope.