Flat Roof & Torch Down in Hamilton, Ontario
SBS modified bitumen and torch-down systems that handle Ontario's freeze-thaw cycles without bubbling, splitting, or failing at the seams. Residential and commercial.
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Quick answer: Flat roof installation in Hamilton typically costs $5,000–$15,000 for residential applications. Torch-down SBS modified bitumen is the standard choice for Hamilton's climate — it handles freeze-thaw cycling better than older BUR systems and costs less than EPDM on smaller roofs. A professionally installed torch-down flat roof lasts 15–25 years in Ontario conditions with proper maintenance.
Our Work in Hamilton
Three Signs You Need Flat Roof & Torch Down
🫧 Your flat roof bubbles or blisters
Blistering indicates moisture trapped between membrane layers — a compromised base sheet. Repair is possible early; widespread blistering requires replacement.
💧 Ponding water lasting 48+ hours
Flat roofs should drain within 48 hours. Chronic ponding accelerates membrane failure and adds structural load.
🏚️ Original 1970s–1990s flat roof
Many Hamilton garage and addition flat roofs from this era have original BUR (built-up roofing) well past service life. Modern SBS torch-down dramatically outperforms these systems.
When You Need It
⚡ Alligatoring surface cracks
When the membrane shows a cracked, scaly pattern, UV degradation has reached the point where self-sealing capacity is gone.
⚡ Water in ceiling near flat roof area
Flat roof leaks almost always appear at parapet walls, drains, or penetrations — targeted repair is often possible before full replacement.
⚡ Roof age over 15 years
Without maintenance records, a professional inspection is the prudent step to assess remaining service life.
⚠️ What Happens If You Wait?
Flat roofs fail slowly and invisibly until they don't. By the time a ceiling stain appears from a Hamilton flat roof, the membrane has usually been compromised for months. Wet insulation adds $1,500–$4,000 in remediation on top of the roof cost. Structural deck saturation can push total costs past $20,000.
6 Steps From Call to Complete
What to expect every time Bosani Roofing shows up at your home.
Inspection & Drainage Assessment
We evaluate membrane, insulation, drainage, and substrate before recommending repair or replacement.
System Selection
We recommend the right membrane — torch-down SBS, EPDM, or modified bitumen — based on slope, climate, and budget.
Tear-Off
Old membrane and failed insulation removed. Deck dried and inspected before new material is applied.
Base Sheet Installation
Mechanically fastened base sheet creates the foundation layer and improves wind uplift resistance.
Torch-Down Application
SBS modified bitumen cap sheet applied with propane torch — heat-welded seams are the most leak-resistant method for Ontario flat roofs.
Drainage Test & Sign-Off
Drains tested, parapet caps inspected, and full membrane walk completed before sign-off.
"Bosani replaced the flat roof on our addition with torch-down. Two Ontario winters later, not a single drip. They also improved the drain slope, which eliminated chronic ponding. Couldn't ask for better."
"Original 1988 flat roof on our garage. Bosani showed me the delamination photos and gave me a fair quote — replacement over repair, which was the right call. Done in a day and a half. Excellent crew."
Frequently Asked Questions
Honest answers about Flat Roof & Torch Down in Hamilton, Ontario.