FLAT AND TORCH-ON ROOFING IN NANAIMO
Recurring flat roof leaks usually mean the wrong repair method was used. Our Red Seal roofers heat-weld torch-on membrane systems designed to stop water permanently on Vancouver Island's wettest roofs.
Price Guarantee & 10-year Workmanship Warranty
Red Seal Roofers with 15+ Years of Experience
Free Roof Inspections & Repair Quotes
Friendly Staff
‘Great team experience and workers! A special thanks for a great job done to Emily & Travis ! A GREAT addition to Roof Rangers ! I highly recommend if you are contemplating any roof updates repairs or moss removal , GO Roof Rangers A+++’
- Kenneth.
FLAT ROOF AND TORCH-ON SERVICES WE DELIVER
TORCH-ON MEMBRANE REPAIR AND REPLACEMENT
Torch-on roofing (also called "modified bitumen") uses layers of reinforced membrane that are heat-welded together with a propane torch. This creates a seamless, fully bonded waterproof surface. Our team replaces failing membranes with properly sequenced multi-layer systems, sealing every seam and overlap so water has no path into your building. A correctly torched membrane bonds directly to the substrate, which is why it outperforms adhesive-applied patches that can lift in Vancouver Island's constant moisture. Every replacement includes new flashing integration at walls, vents, and penetrations, because those junctions are where most flat roof failures actually begin.
FLAT ROOF LEAK DETECTION AND EMERGENCY REPAIR
Flat roof leaks rarely appear directly below the entry point. Water travels along the membrane surface, pooling at low spots or seeping through fastener holes before showing up as a ceiling stain metres away. We trace leaks back to their origin using systematic inspection rather than guesswork, then apply heat-welded membrane patches that become part of the existing system. For emergency roof repair situations, we respond promptly to prevent further interior damage to insulation, drywall, and electrical systems.
PONDING WATER CORRECTION AND DRAINAGE IMPROVEMENTS
Standing water on a flat roof accelerates membrane breakdown and adds structural weight your framing may not be designed to carry. We correct ponding by adjusting slope with tapered insulation, installing additional scuppers or internal drains, and verifying that water clears within 48 hours of rainfall. Proper drainage is the difference between a 20-year membrane and one that fails in under 10.
COMPLETE FLAT ROOF TEAR-OFF AND NEW INSTALLATION
When patching can no longer keep up with deterioration, a full tear-off and new roof installation are the right call. We strip all existing material down to the deck, inspect sheathing for rot or soft spots, replace damaged sections, and install a complete torch-on waterproof system from underlayment through final membrane. This approach eliminates hidden problems that layover installations trap underneath.
RESIDENTIAL AND COMMERCIAL FLAT ROOFING
Flat and low-slope roofs appear on garages, additions, carports, multi-unit buildings, and commercial properties throughout Nanaimo and Central Vancouver Island. Whether your flat roof covers 200 square feet or 2,000, the waterproofing principles are identical: proper membrane bonding, flashing-first detailing, and moisture-focused ventilation. We handle both residential roofing and commercial roofing flat-roof projects with the same installation standards.
HOW WE REPAIR OR REPLACE YOUR FLAT ROOF
Every flat roof project follows a structured process built around waterproofing integrity. Here's what to expect when you work with our team.
Inspection and Leak Tracing
We examine the entire membrane surface, all flashings, penetrations, drains, and the roof deck condition to identify every failure point.
Scope and Recommendation
You receive a clear written assessment explaining whether targeted repair, partial replacement, or full tear-off is the most effective solution.
Preparation and Tear-off
The damaged membrane is removed. The deck is inspected for rot, soft spots, or fastener damage. All compromised material is replaced before new layers go down.
Torch-on Membrane Installation
Reinforced bitumen membrane is heat-welded in overlapping layers, creating a fully bonded waterproof surface with no exposed seams or adhesive-only joints.
Flashing and Drainage Detailing
New metal flashings are integrated at every wall, vent, skylight, and penetration. Drainage paths are verified to prevent ponding.
Final Inspection and Cleanup
We confirm watertight integrity across the entire system, remove all debris from your property, and walk you through the completed work.
Contact our team today to discuss your roofing service requirements.
IS TORCH-ON FLAT ROOFING RIGHT FOR YOUR PROPERTY?
Not every roof problem calls for the same solution. Flat and low-slope roofs operate under different physics than pitched roofs, and choosing the wrong approach leads to repeat failures. Use these guidelines to determine whether torch-on membrane work is the right path for your situation.
Roof Slope
Torch-on systems are engineered for flat and low-slope surfaces where water does not shed by gravity alone.
Repair History
If previous patches have failed repeatedly, the issue is likely the method, not the materials. Heat-welded membrane eliminates the adhesion failures common in surface-applied repairs.
Building Use
Flat roofs on occupied spaces (living areas, offices, and rental units) require watertight certainty. Torch-on membrane provides the highest waterproofing standard available for low-slope applications.
When Appropriate
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Your property has a flat or low-slope roof (less than 2:12 pitch) that is leaking, ponding water, or showing membrane blisters, cracks, or lifted seams.
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You've had a flat roof patched before, and the leak returned within one or two rainy seasons, which typically indicates the original repair used surface-applied sealants rather than heat-welded membrane bonding.
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If your flat roof has leaked more than once after repairs, the repair method is the problem. A properly heat-welded torch-on membrane system, installed by a team with specific flat roof expertise, is the permanent solution.
When Not Appropriate
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Your roof has a standard pitch (4:12 or steeper). Sloped roofs perform better with shingle, metal, or cedar systems. A torch-on membrane is not designed for steep applications.
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The leak originates from a skylight seal, chimney flashing, or gutter backup rather than the membrane itself. We'll identify the true source during inspection before recommending any membrane work.
FLAT ROOFING QUESTIONS
Check the answers to some frequently asked questions:
CONFIRM YOUR FLAT ROOF IS IN THE RIGHT HANDS
A flat roof leak that keeps returning after repairs is a method problem, not a material problem. Our Red Seal roofers with 15+ years of certified trades experience will inspect your flat roof at no cost, identify the real failure point, and provide a written scope with our price guarantee.