Have you ever noticed that icicles often form heavily on one side of a building but not the other? The answer comes down to sunlight and heat loss.

• Sun Exposure: The side of a roof that gets more sun during the day will have melting snow, which then refreezes into icicles when the temperature drops at night.

• Heat Escaping: If a house loses heat through its attic, snow will melt unevenly. This often leads to icicles and dangerous ice dams.

• Wind Direction: Wind can affect where icicles form, especially if drifting snow accumulates more on one side.