Charleston Roofing & Exteriors LLC

What is an Ice Dam?


Posted in: Roof Repairs


An ice dam is ridge of ice that forms along the edge of the roof of your Charleston home, which literally creates a dam that prevents your roof from shedding water and snow. Ice dams will prevent melting snow from draining off of your roof.

As the water rests at the edge of the ice dam it may leak through the roofing which can cause damage to your walls, insulation, ceilings. The moisture may also soak your roofing structure and cause it to begin to rot.

How Do Ice Dams Form?

Ice dams occur only when three conditions are in place:

  • snow cover

  • freezing outside temperatures

  • and heat from inside your home escaping through the roof.

The snow at the top of your roof will melt because of the heat escaping from your Charleston home. As it runs down the roof, it begins to freeze again. This leaves ice at the end of your roofing—an ice dam–which will cause major problems for your roofing.

Ice dams are a major problems for Charleston homeowners because they can cause water to leak through your roofing, which in turn can cause a host of other issues:

Although the primary cause of melting snow is your home losing heat, it can also happen because of sunlight. And it doesn’t require sudden or intense warmth.. With temperatures as low as 14° F outdoors and 23° F in the attic, enough sunlight can be transmitted through six inches of snow to cause it to start melting on the roof.

What problems can ice dams cause?

Ice dams are a major problems for Charleston homeowners because they can cause water to leak through your roofing, which in turn can cause a host of other issues:

  • Rotting roof decking, exterior and interior walls, and framing.

  • Mold growth (which can in turn cause respiratory issues).

  • Damaged insulation.

  • Wet insulation won’t work very well, and chronically wet insulation won’t even decompress once it dries. Damaged insulation will allow more heat to escape, will lead to more ice dams, creating a vicious cycle that results in more and more damage.

What steps can I take to prevent ice dams from forming?

There are some things you can do to ensure ice dams never form in the first place:

  • Install a metal roof. You still might get ice formations with a metal roof, but water won’t ever leak through. Snow and ice are also much more likely to slide off of metal than other forms of roofing.

  • Make sure your attic is adequately sealed. If you can keep heat out of the attic, you’ll see the whole problem go away.

  • Move or elevate any exhaust systems near the top of the roof. They may be melting a lot of the snow.

  • Remove any snow from your roof as soon as possible.

If you’ve had trouble with an ice dam and your roofing is damaged in any way, call Charleston Roofing and Exteriors, LLC for an inspection or repairs today at 843-203-5555, or fill out our online request form.


Charleston Roofing & Exteriors LLC