Ontario winters can be brutally unforgiving—especially on your roof. With heavy snowfall, freezing rain, ice dams, and temperature swings, your roof takes a beating from December to March. If it’s not properly maintained, small problems can quickly turn into expensive emergencies.
Whether you’re a homeowner or property manager, winter prep isn’t optional—it’s essential. Here’s how to prepare your roof for Ontario’s harsh winter conditions and prevent damage, leaks, and costly repairs.
1. Schedule a Professional Roof Inspection
Before the first snow falls, have a licensed roofing contractor inspect your roof for:
- Missing or loose shingles
- Cracked flashing or seals around vents
- Signs of sagging or water pooling
- Worn-out caulking or exposed fasteners
A pre-winter inspection identifies weak spots before snow, wind, and ice test your roof’s limits.
2. Clear Debris from Gutters and Roof Surface
Leaves, sticks, and debris trap moisture and block proper drainage—especially in the valleys of your roof or along the gutterline. When snow builds up, clogged gutters lead to ice dams, which cause water to back up under shingles and into your home.
Action Steps:
- Clean gutters and downspouts
- Remove debris from roof valleys
- Install gutter guards if needed
3. Check Attic Ventilation and Insulation
One of the leading causes of ice damming is poor attic insulation and ventilation. If warm air escapes from your home and heats the roof, it melts snow unevenly, causing refreezing at the edges.
Ensure your attic has:
- Adequate insulation (minimum R-60 recommended for Ontario)
- Proper airflow through soffits, ridge vents, and baffles
- No signs of mold or moisture buildup
Good attic airflow keeps your roof cold and reduces the chance of ice dams forming.
4. Trim Overhanging Tree Branches
Branches hanging over your roof can:
- Break off under snow weight and damage shingles
- Drop more debris into your gutters
- Rub against your roof in high winds
Trim trees back at least 6–10 feet from your roofline to reduce risk.
5. Install Snow and Ice Shields (if Needed)
If your roof is prone to heavy snow accumulation or past ice dam issues, consider adding:
- Ice and water shield membrane under shingles in vulnerable areas
- Snow guards to prevent large sheets of snow from sliding off
- Heat cables near gutter edges to keep water flowing
These are especially useful for low-slope roofs or north-facing roof sections that get limited sunlight.
6. Check Flashing and Seals Around Penetrations
Chimneys, skylights, plumbing vents, and satellite mounts are common leak points. Winter winds and freeze-thaw cycles will exploit any weaknesses.
Inspect for:
- Cracked or deteriorated flashing
- Rust around metal components
- Gaps or separation in sealant or caulking
Repairing these areas now can save thousands in interior damage later.
7. Have a Snow Removal Plan
Don’t wait until the roof is buried. Deep snow increases load stress and can lead to leaks, ice damming, or even collapse on flat or low-slope roofs.
Tips:
- Use a roof rake to safely remove snow from the ground
- Never climb a snowy roof without proper safety gear
- Hire a professional for heavy accumulation or steep slopes
Final Thoughts
Winter in Ontario is no joke—but your roof doesn’t have to suffer for it. A few proactive steps in the fall can protect your home, extend your roof’s lifespan, and prevent costly winter emergencies.
Act now—before the snow hits. A well-prepared roof isn’t just about surviving winter. It’s about owning it.