Until today, we have not seen icicles hanging from our roof, something that was a frequent occurrence at our prior homes. The pictured icicles looked like a frozen crashing wave and were only present on our garage, which is unheated and uninsulated. In the winter, the air temperature in the garage is always higher than the outside air due to three sources of heating; (1) solar heating of the outside walls, (2) thermal bleed from the wall shared with the house, and (3) the heat thrown off by the electric cars after being driven. It is easy to imagine a scenario where the garage roof becomes warm enough to melt snow while the outside air temperature is below freezing. By contrast, the roof over our living areas are highly insulated and made from light-colored aluminum which reflects solar radiation. The surface is much less likely to ever become warm enough to melt snow while outside temperatures are cold enough to make icicles.