Signs your roof needs replacing after an Ontario winter

Why winter is hard on roofs here

Barrie averages about 223 cm of snow a year, and Midland closer to 280 cm, based on Environment Canada’s 1981–2010 normals. The snow itself is not the main issue. The damage comes from freeze and thaw. Heat from the house melts snow on the upper roof, the water runs down to the cold overhang, and it refreezes into an ice dam. More water then backs up behind the dam and under the shingles. Strong winter winds can also lift and crack older shingles.

Stay safe first

Do not climb onto a roof that is wet, icy, or still has snow on it. Everything on this list can be done from the ground, with binoculars, or from inside the attic.

From the ground

• Missing, lifted, or cracked shingles, especially along ridges and edges.
• Curling or cupping at the shingle edges, which is a sign of age.
• Granules piling up in eavestroughs or at the bottom of downspouts.
• Bent or pulled-away eavestroughs from ice weight.
• Damaged flashing around the chimney, vents, or skylights.
• A sagging roofline. Call a professional soon if you see this.
• Moss or dark streaks, often on north-facing slopes under trees.

Inside the house and attic

• Water stains on ceilings or upper walls, especially near exterior walls. These are a classic ice dam sign.
• Damp or matted insulation, or dark stains on the underside of the roof boards.
• Daylight showing through the roof boards.
• Frost or heavy condensation on nails in the attic in winter, which points to a ventilation or air-leak problem.

Repair or replace?

A few missing shingles or one leaking vent on a fairly new roof is usually a repair. Common repairs, such as a new plumbing vent boot or replacing a handful of shingles, often cost a few hundred dollars, based on 2026 Ontario price guides.

It is more likely time to replace when:

• The roof is past about 20 years for standard asphalt shingles.
• Shingles are curling or losing granules across most of the roof, not just one spot.
• You have leaks in more than one place, or ice dam leaks every winter.
• The deck feels soft or looks damaged from the attic.

Patching a very old roof can break the seals on nearby shingles, so ask the roofer to be honest about whether a repair is worth it.

Fixing ice dams for good

Removing the ice is a short-term fix. The longer-term fix is usually in the attic: sealing air leaks from the house, adding insulation, and improving ventilation so the roof stays cold. When you replace a roof, ask about ice and water shield along the eaves and valleys.

Insurance

Sudden damage, such as wind or a fallen tree, may be covered by home insurance. Wear and age usually are not. Take photos before anything is moved, and call your insurer early. Your policy decides what is covered.

Get one local quote

Request a free roofing quote from one local roofer in Barrie, Innisfil, Bradford, Orillia, or Midland. For costs, see our roof replacement cost guide.