Just as warm sunlight can quickly turn a block of ice cream into a puddle, a toasty attic can make a mound of snow on a roof gush like a waterfall. Similarly, as Niagara Falls can freeze given enough cold air, water freshly fallen over a roof’s edge can turn solid adding large amounts of weight.
Ice dams form when roofs are above freezing temperature at higher spots, and below freezing at lower spots. This may seem like too perfect a balance to cause any problems, but any snow warmer than freezing, believe it or not, will melt.
When this happens, the liquid has nowhere to go but straight down. And down it goes into the colder half of the roof, where it gets trapped and solidifies. Depending on how much snow there is up top, the ice can continue to expand. Meanwhile, the water in the top half flows through any dents and openings it can find, entering deeper surface levels and potentially wearing out the attic ceiling.
In order stop disaster before it starts, you want your roof to be clear as often as possible; the less snow on the housetop, the drier. However, being wintertime, large piles of snow are likely to keep coming as quickly as breaking news stories. Why constantly put your body and roof at risk by walking on top of the roof yourself? A contractor can help maintain a roof’s structural integrity more effectively, and in a shorter time.