What Are Ice Dams?
Ice dams form when:
- Heat from your home warms the roof and melts snow
- Melted water runs down to colder eaves and refreezes
- Ice builds up, creating a "dam" that traps water
- Trapped water backs up under shingles, causing leaks
❄️ At Sierra foothill elevations (2,000-3,000'), the combination of snow, freeze-thaw cycles, and pine debris creates perfect conditions for ice dams.
Ice Dam Risk by Community
| Community | Elevation | Snowfall | Ice Dam Risk |
|---|---|---|---|
| Alta Sierra | 2,800' | 10-20" | High |
| Lake of the Pines | 2,400' | 5-15" | Moderate-High |
| Grass Valley | 2,400' | 5-15" | Moderate-High |
| Nevada City | 2,500' | 8-18" | High |
| Penn Valley | 1,800' | 2-8" | Low-Moderate |
Prevention Solutions
Heat Cables
Electric cables keep gutters warm enough for continuous drainage
$15-25/ft installed
Excellent
Improved Insulation
Reduces heat loss through roof that causes snow melt
Varies
Good
Proper Gutter Slope
Water drains before it can freeze
$200-600
Helps
Micro-Mesh Guards
Prevents debris clogs that trap water and freeze
$18-32/ft
Helps