Skylights are a top renovation request and a top leak callback. The product rarely fails – improper flashing does. Here’s what to know for 2026.
Fixed vs venting:
- Fixed: light only
- Manual venting: cord/wand operation
- Solar-powered venting (VELUX most popular): auto-close rain sensor, no wiring required
Venting skylights cost $300-$800 more than comparable fixed units.
Flashing: use manufacturer kit, not generic step flashing
Manufacturer-specific flashing kits are engineered for each product and roof pitch. Generic step flashing voids most warranties and is the leading cause of leaks.
Condensation vs actual leak:
Warm interior air hitting cold skylight glass in Ontario winters = condensation that drips. Solution: verify curb insulation, seal interior shaft vapour barrier, keep indoor RH below 50% in winter. Triple-pane skylights reduce condensation.
GTA cost ranges (2026):
- VELUX fixed skylight (supply only): $400-$800
- VELUX solar venting (supply only): $800-$1,800
- Full installation (new penetration, light shaft): $1,500-$3,500/unit
- Like-for-like replacement (same opening): $800-$2,000
- Sun tunnel (tubular, no shaft): $600-$1,200 installed
- Total new VELUX venting project: $2,500-$5,500
Ontario skylight and roofing questions at home.renovation.reviews