A. Corresponding Editor Henri de Marne responds: In addition to having ice-dam problems, this roof is poorly insulated and may also have problems with condensation within the unvented cathedral ceiling. Building a cold roof will probably solve the ice-dam problem, but it will neither improve the insulation level nor address the issue of possible condensation.
You should first remove some of the sheathing at the eaves to inspect the insulated space and check for possible water damage caused by the ice dams. Then remove some of the sheathing near the ridge to check for possible damage caused by condensation. Wet insulation should be replaced and wet wood allowed to dry, to prevent further damage and...
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