Most everyone here in New England knows why the ice dam leak occurs, so I will not go into great detail on the anatomy of an ice dam leak. However, let me give you, the reader, a quick summary to refresh your memory. Snow accumulates on the roof. The exterior wall of the house at the eaves loses heat, usually due to poor insulation. The heat travels up through the roof and begins to melt the snow. The outside temperature freezes the melt and it climbs up the roof under the shingles.This cycle lasts day after day and then it happens … the warm day, the thaw. The water is now under the shingles and makes its way into the house usually along the interior wall at the eave intersection of the roof.
You call your contractor or roofer and they will tell you that the roof was not properly installed. Some will tell you that the Insulation needs to be addressed or that the ventilation is not working properly. Can it be fixed? Yes. Anything can be fixed. In some cases, you will want to reconcile your roof to include proper overhangs and adequate sofit vents with the correct ratio to the ridge vent or gable vents to create convection of air up the roof to keep it cold. Someone might even tell you to build a cold roof. There's always the heating wires you can lay out on the roof, or maybe you could spring for a metal skirt. That 'sa 2 foot metal edge around the perimeter of the roof in hopes that the ice and snow will slide off instead of damaging. What typically happens with these solution is the ice dam forms further up the roof just above the recently installed "solution" which can further compound the problem
Some of these solutions could have helped in correcting the problem. But over time, with an asphalt roof, one will end up with more ice dams even if the ventilation has been corrected.