The winter weather can create new roof problems and expose existing ones. Consider, nearly four in 10 U.S. homes are estimated to have roofs that are rated as “moderate” or in “poor” condition. As such, many properties may be at risk when colder weather and heavy snowfall arrives.
“Most homeowners don’t realize their roof is vulnerable until it’s too late,” explains Jeff Berzolla, CEO of Instant Roofer, a platform that uses AI-powered roof calculators to provide roofing estimates nationwide. “The signs are often there months before the first snowfall, but people miss them because they don’t know what to look for.”
Berzolla says a typical $300 roof inspection and minor repairs could prevent $15,000 to $30,000 in emergency damage costs later on.
Berzolla shares the key warning signs that indicate a roof may be in trouble.
1. Sagging or uneven roof surfaces
One of the most serious red flags is a roof that appears to sag or dip in certain areas. This indicates structural weakness that could lead to catastrophic failure under the load of snow. “When you see sagging, you’re looking at compromised structural integrity,” says Berzolla. “Snow can weigh 20 pounds per square foot when wet, and a weakened roof simply can’t handle that kind of pressure.”
What to do: Contact a structural engineer immediately. This isn’t a DIY fix and requires professional assessment before winter arrives.
2. Missing, cracked or curling shingles
Damaged shingles create entry points for moisture, which can freeze and expand, causing further damage during winter months.
What to do: Replace missing shingles and repair cracked ones before the first snowfall. Even small gaps can lead to major problems when ice forms.
3. Ice dams forming along gutters
If you noticed ice dams last winter, your roof likely has insulation or ventilation issues that will worsen this year. “Ice dams form when warm air escapes through your roof, melting snow that then refreezes at the edges,” Berzolla explains. “This creates a dam that forces water back up under your shingles.”
What to do: Improve attic insulation and ventilation. Clean gutters thoroughly and consider installing heat cables as a temporary solution.
4. Interior leaks, damp patches or water stains
Any signs of water intrusion inside your home indicate your roof's protective barrier is already compromised.
What to do: Trace the source of leaks immediately. Water can travel far from the actual roof damage, so you may need professional help to locate the problem area.
5. Blocked or damaged roof vents
Proper airflow prevents ice buildup and helps maintain consistent roof temperature. Blocked vents create hot spots that lead to uneven snow melting.
What to do: Clear debris from vents and replace damaged vent covers. Ensure soffit vents aren’t blocked by insulation from inside the attic.
6. Excessive icicles or gutter stress
While some icicles are normal, large formations indicate poor drainage and potential structural stress on your gutters and roof edge. “When gutters start pulling away from the house or you see oversized icicles, that’s your roof telling you there’s a drainage problem,” Berzolla notes.
What to do: Clean gutters completely and check that downspouts direct water away from your foundation. Repair any loose gutter brackets.
7. Visible granule loss on asphalt shingles
Excessive granules in gutters or bare spots on shingles mean your roof’s protective coating is wearing away, making it vulnerable to winter damage.
What to do: If granule loss is widespread, a roof replacement is likely needed. Isolated areas can be repaired with new shingles.