Ice dams build up when heat from the house melts roof snow that then freezes again along the cold overhang, and the pooled water backs up beneath the shingles. The leak shows up as a ceiling stain, but the wet insulation above it holds most of the water.
How the attic and ceiling get dried
The crew opens the ceiling at the stain, removes wet insulation and checks the roof deck and framing with a moisture meter. The structural drying setup puts air movers and dehumidifiers in the attic and the room below, and the readings show when the cavity is dry enough to close.
- Insulation touched by melt water is bagged and removed
- The roof deck and rafters are read with a meter
- The roofer is told what the meters found
- Walls below the leak are checked for hidden moisture



