Flat roof repair in Greater Toronto Area
Leak repair, repairs, replacement and maintenance of flat roofs in 15 cities across the GTA, for homes and businesses.
Flat roofs in the GTA
The GTA has more flat roofs than anywhere else in Ontario: rear additions and garages on older Toronto houses, low-rise condos and rental buildings, post-war plazas and the business parks and warehouses of Peel, York, Halton and Durham.
Snow loads here are lower than in most of the province, but summer storms drop a lot of rain fast. Drains, scuppers and the flashings around them cause many of the leaks we see.
Cities in Greater Toronto Area
Roof design climate by city
| City | Ground snow load | 15-minute rain | January design temperature |
|---|---|---|---|
| Toronto | 0.9 kPa | 25 mm | -18 °C |
| Mississauga | 1.1 kPa | 25 mm | -18 °C |
| Brampton | 1.3 kPa | 28 mm | -19 °C |
| Vaughan | 1.1 kPa | 26 mm | -20 °C |
| Markham | 1.3 kPa | 25 mm | -21 °C |
| Richmond Hill | 1.5 kPa | 25 mm | -21 °C |
| Oakville | 1.1 kPa | 23 mm | -18 °C |
| Burlington | 1.1 kPa | 23 mm | -17 °C |
| Milton | 1.3 kPa | 25 mm | -18 °C |
| Pickering | 1 kPa | 23 mm | -19 °C |
| Ajax | 1 kPa | 23 mm | -20 °C |
| Whitby | 1.2 kPa | 23 mm | -20 °C |
| Oshawa | 1.4 kPa | 23 mm | -19 °C |
| Newmarket | 2 kPa | 28 mm | -22 °C |
| Aurora | 2 kPa | 28 mm | -21 °C |
Source: Ontario Building Code, Supplementary Standard SB-1, Table 1.2. Values are design figures, not forecasts.
What this means for your roof
Snow loads are moderate here. Most damage comes from freeze–thaw cycles, ice at the drains in late winter and heavy summer rain.
Whatever the climate, most leaks start at details: seams, flashings, drains, vents and skylights. See roof problems for causes and fixes.
Starting prices
| Item | Starting price |
|---|---|
| Small leak repair (patch, seam or puncture) | from $350 per repair |
| Roof inspection with written photo report (house) | from $250 per roof |
| House flat roof replacement (about 1,000 sq ft) | from $8,000 per roof |
| Commercial roof replacement | from $8 per sq ft |
Starting prices in CAD before 13% HST, based on typical Ontario contractor rates (mostly Toronto and the GTA). The final price depends on roof size, access, the layers to remove, the membrane, drains and flashings, and is confirmed in your written quote.
Flat roof work in Greater Toronto Area
Do you work outside the cities listed for the GTA?
Often, yes. Tell us the town in the quote form. Smaller towns are quoted with travel time included.
Which roofs do you work on in the GTA?
Houses, townhouses, garages and additions, condo and apartment buildings, plazas, offices and warehouses. See property types.
Which flat roof material suits this climate?
EPDM, TPO, PVC and modified bitumen all perform in Ontario when installed and detailed well. See choosing a flat roof material.
Leak, damage or an old flat roof?
Send a few details and photos. We reply by email with next steps and a written quote.