Water Intrusion Ice Damming Assessments

Water intrusion from ice damming can damage the interiors of buildings. Unlike traditional roof leaks, ice damming leaks occur from a particular set of weather conditions and in specific building settings. Ice dams typically form at the bottom of roof slopes or at roof terminations when snow accumulations melt and drain to unheated roof edges where they refreeze. This can cause water to back up under the roof coverings damaging the structure beneath. This paper outlines key points in the assessment of roof leaks to determine whether they were attributable to ice damming. Hydrostatic and hydrokinetic roofing types and their susceptibility to ice damming are discussed. It indicates why hydrokinetic roofs are susceptible to water intrusion from ice damming. The constructions of the building envelope wall and roof insulation are also considered. Several case studies are reviewed to determine whether leaks were attributable to ice damming conditions or other deficiencies.