How much does flat or commercial roof replacement cost in Toronto?

Costs vary widely by membrane type, roof size, and access. A straightforward EPDM or TPO re-roof on a residential addition often runs several thousand dollars, while larger commercial buildings with tear-off, insulation upgrades, and drainage work can run into six figures. Get itemized quotes from at least two or three contractors, since material choice and labor scope drive most of the price difference.

How often does a flat roof need to be replaced?

Most flat roofing systems last 15 to 25 years depending on the membrane type, installation quality, and maintenance. TPO and EPDM tend to sit at the longer end when properly installed and maintained, while older built-up tar and gravel systems often need attention sooner. Regular inspections, especially after harsh winters, catch small issues before they become full replacements.

What should I expect during a flat roof inspection or repair visit?

A thorough contractor will check for ponding water, membrane seams and flashing around penetrations, drain condition, and signs of moisture in the insulation below. For repairs, expect a walkthrough explaining the cause of the leak, not just where it surfaced, since water often travels before it drips through the ceiling.

How can I tell if a roofing contractor does quality work?

Look for manufacturer certifications tied to the specific membrane system, clear separation between material and workmanship warranties, WSIB and liability insurance, and a track record of positive reviews that mention follow-up service, not just the initial install.

Flat & Commercial Roofing in Toronto

Flat and low-slope roofing covers a different set of problems than the shingle roof on a house down the street. Think TPO, EPDM rubber, modified bitumen, and built-up (tar and gravel) systems on top of commercial plazas, warehouses, apartment blocks, and the flat-roofed additions common on older Toronto homes. The work involves membrane welding or torch-down application, proper drainage and slope to avoid ponding water, flashing details around vents, parapets, and HVAC curbs, and insulation upgrades that affect both energy bills and roof lifespan. We've listed 67 businesses in Toronto that handle this kind of work, ranging from small crews focused on residential flat-roof additions to larger operations that service industrial and multi-unit properties.

When you're comparing contractors, ask about the membrane system they actually specialize in (not every crew is equally skilled across TPO, EPDM, and modified bitumen), how they handle drainage and ponding, whether they carry manufacturer certifications that unlock extended warranties, and what their own workmanship warranty covers separately from the material warranty. Insurance and WSIB coverage matter more here than on typical residential jobs, given the equipment and height involved.

Our scoring weighs review volume and consistency, how contractors respond to negative feedback, licensing and insurance signals, and longevity in the trade. For a full breakdown of the criteria, see our methodology page. If you want our editors' ranked shortlist rather than the full directory, check the best roofing contractors in Toronto guide.

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All flat & commercial roofing in Toronto, ranked by score and relevance

67 businesses, scored on recent reviews. The order weighs each business's overall score by how much of its reviewed work is flat & commercial roofing, so a lower-scored specialist can rank above a higher-scored generalist.

Advanced Flat Roof Systems

5.0(58)✓ Google-verified

Denys and his crew deliver flat roof work that consistently exceeds expectations. Reviewers praise their responsiveness, attention to detail, and ability to complete complex jobs in one day without mess or surprises. One reviewer noted they came out in an emergency after a damaging storm and went well beyond the original scope. The team provides transparent estimates, handles old or problematic roofs with skill, and cleans thoroughly after finishing. Their 10-year warranty gives confidence in the work. Denys shows particular strength in early consultations, identifying real problems without upselling, and communicating clearly through each phase. Customers acknowledge the pricing is not the cheapest but value the result: roofs that work reliably and are built right the first time.

Roof Inspection & MaintenanceRoofing ContractorRoof Replacement & Installation

Flat & Commercial Roofing in Toronto

All flat & commercial roofing in Toronto, ranked by score and relevance

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