Flat roof prices
Starting prices for the most common flat roof jobs. Every roof is different, so your price is set after a roof visit or from good photos and measurements.

Repairs and visits
| Item | Starting price |
|---|---|
| Small leak repair (patch, seam or puncture) | from $350 per repair |
| Temporary leak protection (urgent call) | from $350 per visit |
| Flashing repair or replacement | from $500 per repair |
| Roof drain or scupper repair | from $800 per drain |
| Skylight, curb or vent reflashing | from $350 per opening |
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.
Inspections and maintenance
| Item | Starting price |
|---|---|
| Roof inspection with written photo report (house) | from $250 per roof |
| Commercial roof inspection and report | from $450 per roof |
| Maintenance visit (drains, seams, flashings, photos) | from $295 per visit |
Commercial inspections cover larger roofs with drains, rooftop units and several roof areas.
Replacement by roof
| Item | Starting price |
|---|---|
| Small flat roof replacement (garage, porch or addition) | from $4,000 per roof |
| House flat roof replacement (about 1,000 sq ft) | from $8,000 per roof |
| Commercial roof replacement | from $8 per sq ft |
Includes tear-off of one existing layer, disposal and a new membrane. Extra layers, rotten deck boards and new insulation are priced separately.
Replacement by membrane
| Item | Starting price |
|---|---|
| EPDM roof replacement | from $8 per sq ft |
| TPO roof replacement | from $9 per sq ft |
| PVC roof replacement | from $11 per sq ft |
| Modified bitumen (torch-on or SBS) replacement | from $8 per sq ft |
| Built-up (tar and gravel) roof replacement | from $9 per sq ft |
Per square foot rates fall as roof size grows. Small roofs have a minimum price.
Coatings, insulation and decks
| Item | Starting price |
|---|---|
| Roof coating (restoration) | from $3 per sq ft |
| Tapered insulation (added to a replacement) | from $2 per sq ft |
| Rooftop deck waterproofing membrane | from $22 per sq ft |
undefined
What changes the price
Size and shape
Small roofs cost more per square foot. Many corners, parapets and openings add hours.
Layers to remove
Two or three old layers mean more tear-off, more disposal and sometimes a heavier load on the structure.
Deck and insulation
Wet insulation and soft deck boards are replaced before the new membrane goes on.
Drainage
Fixing ponding with new drains or tapered insulation adds cost but stops the cause.
Access
High roofs, tight lanes, no place for a disposal bin or materials lifted by crane add time.
Membrane and details
The membrane, flashing metal, skylights, vents and rooftop units all affect the quote.
What is in a quote
Your written quote lists the area, what is removed, the deck and insulation work, the membrane, flashings, drains and clean-up. It says what is a repair and what is a replacement.
Read what a flat roof costs in Ontario and how to prepare for a roof quote to compare quotes on the same terms.
Leak, damage or an old flat roof?
Send a few details and photos. We reply by email with next steps and a written quote.