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Q.We built a custom home for a client in west Michigan a couple of years ago, and the home has had problems with ice ever since. It's a 1,450-square-foot ranch with cathedral ceilings and many can lights throughout. We used blown fiberglass insulation in the ceiling assemblies. From the beginning, the can lights (IC-rated) overheated and tripped their thermal-protection breakers. We finally resorted to pulling the insulation away from the housing of the can lights so they TAs a result, the heat from these lights now warms up the roof and has created a horrible ice problem instead. Last fall we even added four pot vents to the back of the roof in addition to the soffit-to-ridge venting. The homeowner called to report that the pot vents have improved the situation but not completely. I drive by this home frequently and see ice buildup there while other homes in the area are ice free.

A.Editor Don Jackson responds: The fact that the home your company built is the only one in the neighborhood with ice problems is not going to help your reputation as a quality builder. Adding pot vents to the roof is tantamount to heating the outdoors in an effort to cool the can lights.

Since you seem to be able to reach the can lights from an adjoining attic area, you might be able to place a sealed, insulated box around each can, but there's a chance the overheating problem would come back.

Instead, line up your electrician and drywall finisher. Pull the cans and convert them to track lighting or some other kind of surface-mounted fixtures, then seal up and patch the ceiling, making sure you plug all the holes. Carefully replace the insulation and get rid of the pots, and your problem should disappear. In the future, avoid can lights in cathedral ceilings.