Flat and low-slope roofs cover most of Toronto's commercial buildings, warehouses, multi-unit residential blocks, and plenty of laneway houses and additions too. This category lists 37 businesses in the city that work on these roof types, from small repair outfits to crews that handle full building re-roofs.
What this work involves
Flat roofing is its own trade, separate from the sloped-roof shingle work most residential roofers do. Common systems in Toronto include TPO and PVC single-ply membranes, EPDM rubber, modified bitumen (torch-on or peel-and-stick), and built-up roofing (BUR) with gravel ballast. Contractors in this category also handle roof drains, parapet flashing, insulation upgrades, and the spot repairs that keep an aging membrane watertight between full replacements. Commercial jobs often add complications residential roofers rarely deal with: rooftop HVAC units and curbs to work around, occupied tenants below during construction, and permit or engineering sign-off for larger buildings.
What to look for before hiring
Ask what membrane system they install most often and why they'd recommend it for your building type, since a contractor who only does one system will push it regardless of fit. Confirm they carry commercial general liability insurance and WSIB coverage, and ask for the manufacturer certification behind any warranty they quote (a 20-year membrane warranty is only as good as the installer's certification with that manufacturer). For condo boards and property managers, get a written scope that separates membrane, insulation, flashing, and drain work, since vague quotes are where costs balloon mid-project.
How our scoring works
We rank contractors using verified review volume and rating trends, how consistently they respond to customer feedback, and signals like licensing and time in business. See the full breakdown on our methodology page. For a side-by-side ranked list of the top performers in this category, check our best roofing contractors guide.
