Ontario Roof Replacement 2026: Shingles, Flat Roofs, Ice Shield and Cost Guide

Roofing questions come up constantly here — here’s a consolidated Ontario guide for 2026.

Asphalt shingles (most common):

  • 3-tab largely obsolete; architectural/laminate is the standard (30-50 yr warranties)
  • GTA pricing for 1,500-2,000 sq ft home: $8,000-$14,000 including tear-off, new ice and water shield, architectural shingles
  • Ice and water shield required from eave to 900mm inside exterior wall line (OBC minimum)

Flat roofs (common in Toronto Victorian/bungalow stock):

  • Modified bitumen: $10-$15/sq ft, 15-20 yr lifespan
  • EPDM rubber: $12-$18/sq ft, 20-30 yr lifespan
  • TPO: $12-$16/sq ft, 20-25 yr lifespan

Attic ventilation is the most common warranty-voiding issue. OBC requires 1 sq ft unobstructed ventilation per 300 sq ft attic floor. Balanced intake (soffits) to exhaust (ridge) system is optimal.

Contractor red flags: Cash only, no written contract, same-day pressure, no local address, no WSIB coverage.

What roofing systems have held up best in your GTA neighbourhood?

Ontario roofing help at home.renovation.reviews