The winter months present a number of potential headaches for the homeowner, including ice dams. Ice dams are dams of ice that form on roofs and cause water to back up. Ice dams form when the snow that touches the roof melts, and then that water freezes again before running off your roof.
Gutters are not the only place where ice dams form. Blocked or clogged gutters can fill with ice and provide the foundation for an ice dam.
Ice Dam Prevention