TECHNICAL BRIEF: ICE DAMS

Where ice dams do occur, it is important to understand the causes so that an effective solution can be implemented.

Ice dams are a symptom of poor thermal and air leakage control for roofs in cold winter climates.  When diagnosing the causes of ice dams, it is critical to first determine if the roof system is a vented or an unvented roof (see Roof Configuration above). Never allow bath and kitchen exhaust to terminate in an attic. For more information on ice dams and how to avoid them, please view Fine Home Building's article referenced below. 

Note: Ice dams should not occur in new buildings since following code provisions would control the mechanisms that cause ice dams.  Incidents of ice damming in newer buildings may be reason to seek remedy from the designer, the contractor or both.