A new surface, not a new roof
Roof coating and restoration
A coating adds a fresh waterproof layer over a roof that is worn but still dry underneath. Used on the right roof it saves most of the cost of a replacement. Used on the wrong one it hides a problem.
- For dry, sound roofs
- Silicone, acrylic and more
- Starting price listed
What coating can and cannot do
A coating is a liquid applied by roller or spray that cures into a seamless film. It seals small cracks, resists UV and can reflect heat. It does not fix wet insulation, a rotted deck or a roof that ponds severely. Coatings fail early on wet substrates, because trapped moisture pushes the film off.
Commercial coatings are commonly quoted with a service life of 7 to 20 years, depending on the coating, depending on the product, thickness and conditions, and the coating can often be recoated later. Treat any long-life claim as a question for the product maker, in writing.
Is your roof a good candidate?
| Condition | Coating suitable? |
|---|---|
| Membrane dry, with surface cracking or UV wear | Often yes after cleaning and spot repair. |
| Open seams and loose flashings | Yes, once those are repaired first. |
| Insulation wet in large areas | No. Replace the wet sections first, or the roof. |
| Ponding water that lingers | Only with a plan for slope or drainage, otherwise most coatings wear faster there. |
| Old layers already stacked on the deck | Often not. Layer limits differ by municipality, so a recover may not be allowed. |
The [repair or replace guide](/guides/repair-or-replace-flat-roof/) covers the full decision.
How restoration is done
Moisture check
Visual survey and a few test cuts to confirm the roof is dry enough to coat.
Cleaning
Pressure wash to remove dirt, algae and chalking, and let the roof dry.
Repairs
Primer if required
Some membranes need a primer for the coating to bond.
Coating in coats
Applied at the thickness the product requires, with weather and curing time respected.
Coating starting price
| Item | Starting price |
|---|---|
| Roof coating (restoration) | from $3 per sq ft |
| Flashing repair or replacement | from $500 per repair |
| EPDM 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.
The replacement row is shown for comparison. Prep, repairs and the product chosen move the coating price. See flat roof cost in Ontario.
Questions about roof coatings
Which coating suits Ontario roofs?
It depends on the existing membrane and on ponding. Silicone tolerates standing water well, while acrylic is cheaper but wears faster where water sits. We match the coating to your roof.
Can any membrane be coated?
Most can, with the right primer. Some, such as certain old PVC or heavily weathered bitumen, need testing first.
Does a coating stop an active leak?
Not by itself. Leaks are repaired first, and the coating then protects the repaired roof.
Can I coat in fall?
Coatings need dry weather and temperatures above a minimum for curing, so late fall in Ontario is often too cold. Late spring through early fall is the realistic window.
Leak, damage or an old flat roof?
Send a few details and photos. We reply by email with next steps and a written quote.