I wish I could tell you that ice dams were the homes of cold weather beavers. Unfortunately, that is not the case. Ice dams are ridges of ice that form at the edges of roofs and prevent melting snow from draining off. The backed up water can leak inside of the home. This could cause damage to ceilings, walls, and other areas of the home.
Ice dams are caused by an interaction between the heat loss from a house, outside temperatures, and overall snow cover. There must be snow on the roof. For the ice dam to form, higher portions of the roof’s outside surface must be above the freezing point of 32 degrees. and the lower points must be below this level. The snow on the higher portion of the roof will melt. When it reaches the lower point on the roof it will re-freeze. There you have it. An ice dam.
As water pools behind the dam, it will find small cracks and opening to escape through. This is when you start to have damage occur. The water will first leak into the attic space. From there, it will start to seep into your walls and ceilings. This may cause major damage to your home over time.
There are steps you can take to prevent ice dams and the damage they may cause. You can remove the snow from your roof. You can also do this by using a roof rake or push broom. In an emergency situation, you can create channels for the trapped water to flow though. You can do this with a hose on warmer days. Remember that the channels may be plugged up in a couple of days and this is a temporary fix.
For long term fixes, start your project in the warmer months with plenty of time before snowfall. Make your ceiling air tight. This will prevent warm, moist air from entering the attic space. Once you have done this, you may want to increase your insulation to cut down on heat loss. Once you do this, make sure your roof is capable of handling the extra snow load next winter. These few steps should save your home from water damage in the future.