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Flat Roof Replacement Cost in Markham

Flat Roof Replacement in Markham typically costs $5,600 – $9,600
Based on 800 sq ft, EPDM rubber membrane · excluding 13% HST · compiled 2026 year 10 month

Flat roof (common in older city homes, garages, additions) renovation usually $8–$16/sqft (includes demolition and standard insulation); smaller areas more expensive per sqft, one source lists Toronto at $12–$25.

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Estimate $5,600 – $9,600 (before tax)
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📞 Yongsheng Roofing Company 647-928-1648
📞 Leading Renovation & Construction Company 905-604-8738

Price ranges

Waterproof MaterialsPrice
EPDM rubber membrane
Usually the cheapest option
$7 – $12 / sq ft
TPO membrane$8 – $15 / sq ft
SBS Modified Asphalt
Common Toronto
$9 – $14 / sq ft
Multi-layer asphalt felt (BUR)$11 – $16 / sq ft

Usually includes: Demolition, standard insulation, waterproof membrane, and labor (most data sources). HST 13% not included.

What affects the price

  • Area: Small Roofing (garage, addition) starting prices are high, with higher cost per square foot
  • Area: One source reports Toronto / GTA $12–$25 per sq ft, higher than London and Kitchener area ($8–$16)
  • Tax: Most quotes exclude 13% HST

Local notes for Markham

  • Public data does not separate flat roof prices by city for Greater Toronto Area.

Saving money & avoiding pitfalls

  • Confirm if removal of old materials, insulation thickness, and drainage/flashing treatment are included.

FAQ

Cheapest materials for flat roofs?

Based on public info, EPDM rubber membrane is usually cheapest (approx. $7–$12 per sq. ft.), followed by TPO and SBS modified asphalt; multi-layer asphalt felt is the most expensive.

Sources

Public sources used for the prices on this page (10/2026). Sources measure differently, so we use the range where most of them overlap. For reference only — actual quotes from pros take precedence.

  1. Professional Roofers – Flat Roof Cost in Toronto by Material (2026 Guide)（2025）
  2. RoofRFQ – Flat Roof Replacement Cost in Ontario (2026)（2026-03）
  3. Blue Knight Roofing – Toronto roof cost（2026-07）
  4. Custom Contracting – Ontario roofing cost（2026-10）
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