Welcome to Gaia! :: View User's Journal | Gaia Journals

Ice dams refer to the formation of ice ridges on the edges of roofs, which block the path of melting snow. As the water accumulates between the ridges and snow resulting in a dam-like feature, they are called ice dams. Many times, the retained water leaks into the house and causes severe damage to the roofs, walls, ceilings, insulation, and other places. This again makes a favorable condition for mold and mildew infestations. Hence, the ice should be removed as early as possible to avoid any structural damages.

Causes

As far as the formation of an ice dam is concerned, the environmental temperature, amount of snowfall, and heat loss from the house (precisely the roof) all play an equal role. For example, the accumulation of snow on the roof takes place only when the roof's temperature is below 32 F. Otherwise, the surrounding temperatures higher than 32 F will lead to the snow melting, and thereby not allowing an ice dam to form. Hence, snow accumulates on the roof surface only at low temperature conditions.

Another factor is the loss of heat from the house. Heat escaping through certain parts of the roof will increase the temperature of the roof surface and cause the snow to melt. This water falls along the slope gradient and meets the point where the roof temperature is below 32 F. Here, the melting water collects due to an obstruction by the accumulated ice. Thus, an ice dam is formed on the roof. The size will increase as long as there is continuous running water from above.

Removal

You can prevent the formation of an ice dam by removing the snow on a regular basis. As soon as you notice snow on the roof, remove it with the help of a roof rake or push broom. By doing so, you are eliminating one of the key elements required for an ice dam.

In case the ice dam is already formed, use a shovel, urea fertilizer, and heat tape to get rid of it. Climb on an extension ladder and position yourself safely near the dam. Then, start breaking off the snow and ice from your roof with a shovel. Wipe off the ice with a broom. Ensure that you do it carefully to prevent injuries to yourself or the roof.

http://www.youtube.com/watch?v=2ALVYDEf-D8

The next step is to spread urea over the ice. The high nitrogen content in the urea fertilizer will help to melt the ice. Wait until the fertilizer starts to work, it will cause the icicles to fall. If it does not work, you can sprinkle some more fertilizer. Taking necessary precautions, run the heat tape in an irregular fashion to melt down the remaining ice. You can run the heat tape in the gutter (if any) to create a pathway for water drainage.

If you find it very challenging, then consult a professional. The most effective permanent solution to prevent ice dams is sealing the roof to make it airtight. This will block the passage of warm air escaping from the living room or attic. If possible, install quality insulation systems to minimize heat loss from the interiors.



http://www.buzzle.com/articles/ice-dam-removal.html