While many folks put icicle lights on their roof for decoration. Many people have natural icicles on their roof. Why do some homes form icicles when other do not? It’s all about heat – well escaping heat really. The roof does not have enough insulation so heat is escaping and melting the snow. The melted snow runs down the roof until it gets to the edge. Now the edge of the roof is not so warm (as there is no heat escaping under the edge), and so the melted snow then freezes. Frozen water is then…you guessed it – ice. A little bit of ice and a few icicles is probably nothing to worry about. It’s when lots of snow comes that the problem arises.
Here in the Midwest, we just got hit with our first big snowfall. It can be interesting as you drive around to note which homes get icicles and which homes do not. I find generally any home older than 30-40 years old has a much higher chance of having a poorly insulated/ventilated attic.
Treat the symptom, or fix the problem.
To help with the problem, you can use either a roof rake and keep the edge of the roof clear from snow. You can install heating cables along the edge of the roof which will then melt the ice.
To fix the problem, the attic temperature needs to be cooled, by ventilation and prevention of heat loss from your home. Find a local contractor in your area who will help you diagnose the problem and have a solution as well. A good place to start might be with an insulation contractor. If you attic is easily accessible it could be as easy as rolling out some extra insulation.