Impacts of Snow & Ice on Roofing
How Chicago winters affect your roof and what you can do to prevent damage from snow and ice.
Chicago winters are tough on roofs. Heavy snowfall, ice storms, and freeze-thaw cycles can cause significant damage if you're not prepared. Here's what every homeowner should know.
The Weight of Snow
Snow weight varies significantly:
- Fresh powder: 3-5 lbs per cubic foot
- Packed snow: 15-20 lbs per cubic foot
- Ice: 57 lbs per cubic foot
A 12-inch layer of wet snow on a 1,500 sq ft roof can weigh over 15,000 pounds!
Ice Dam Formation
Ice dams are one of the biggest winter roofing threats:
- Heat escapes through poor attic insulation
- Snow on the roof melts
- Water runs down to the cold eaves
- Water refreezes, creating a dam
- Backed-up water seeps under shingles
This can cause:
- Interior water damage
- Damaged insulation
- Mold growth
- Structural issues
Prevention Strategies
Improve Attic Insulation
Proper insulation keeps heat in your living space and cold in your attic, preventing uneven snow melt.
Ensure Adequate Ventilation
Ridge vents, soffit vents, and proper airflow keep attic temperatures consistent.
Remove Heavy Snow
If accumulation exceeds 12 inches, consider professional snow removal to prevent structural stress.
Install Ice & Water Shield
This underlayment provides an extra barrier against ice dam water infiltration.
Signs of Winter Damage
Watch for these indicators:
- Icicles hanging from gutters (indicates heat loss)
- Water stains on interior ceilings
- Sagging areas on the roof
- Damaged or missing shingles after storms
Common Questions
How much snow is too much for my roof?
Most roofs can handle 20-25 lbs per square foot. Fresh snow weighs about 3 lbs per sq ft, while packed snow is 15-20 lbs. If you have more than 12 inches of packed snow, consider removal.
Can I remove snow from my roof myself?
We don't recommend it. Climbing on an icy roof is extremely dangerous. A roof rake can clear lower sections from the ground, but professional removal is safer for significant accumulation.
What causes ice dams?
Ice dams form when heat escapes through your roof, melting snow that then refreezes at the colder eaves. The solution is proper attic insulation and ventilation.