An ice dam is something that is normally overlooked by many home and business owners, yet it can be known to cause a lot of damage if it isn’t taken care of. So what exactly is an ice dam? It is defined as a ridge of ice that forms on the edge of a roof and sometimes in the gutters, and it prevents the melting snow from draining off of the roof. This water then backs up behind the dam and can leak into a home, causing damage to insulation, ceilings, walls, and more.
An ice dam is caused solely from these three variables: heat loss from the home, amount of snow cover on the roof, and outside temperatures. In order for an ice dam to form, there must be snow on the roof, while the outside surface of the roof must be above 32 degrees while the inner surface is lower than 32 degrees. The snow that is on the surface of the roof that is above 32 degrees will melt. As this melted water flows down, the portion on the roof that is below 32 degrees will freeze – and from there, you have an ice dam!
The dam will then continue to grow as long as it has melting snow to fuel it, but it will limit itself to only the parts of the roof that are on average below 32 degrees. The water above it will then back up behind the ice dam while still in liquid form. It will then find its way into cracks and openings in the exterior roof covering and will flow into the attic space. From the attic, it can then move down the walls, through the ceiling insulation, and stain the ceiling finish as well.
Ice dams don’t have to become a reality for every homeowner though. If you take preventative measures before winter hits, you have a good chance of fighting ice dams and saving yourself some trouble in the long run, and preventing water damage. So how exactly do you prepare for this? First off, cleaning the gutters in your home can easily prevent ice dams from occurring, but it isn’t a complete solution. Gutters will always match the temperature outside and can sometimes be filled with frozen debris, which will then cause the melted water to refreeze when flowing into the gutters.
The best way to avoid and prevent ice dams is by making sure that your attic has the proper ventilation as well as insulation. The usual recommendation for ventilation in the attic is 1 sq ft of vent for every 150 ft or attic floor area, but because every region is different when it comes to the climate, you will want to contact your local professionals in the insulation industry for exact numbers. If you have gable vents at either end of your attic, you can either replace them with larger vents or you can also install an electric vent fan over the inside. These fans are special because they will usually work on a thermostat and will circulate outside air into the attic to keep the temperature inside at a consistent temperature, and therefore this will prevent the uneven melting and refreezing of the snow and ice on your roof.
If you find yourself in a situation where you need to remove an already existing ice dam, it can be dangerous unless you have experience doing so. Ice dam removal can lead to severe personal injury if it isn’t done correctly. Never walk on a snow-covered roof and make sure that if you’re using a ladder you follow the proper instructions.
Once the snow is removed from the roof, the main factor that is necessary to form ice dams will be missing. You will want to use a roof rake and push broom, and you will then remove the snow by carefully pulling it downwards off of the slope of the roof line. Then, carefully chip away a channel through the ice dam so that the water will be able to flow through. Make sure that you stop the channel when you get close to the roofing. It isn’t necessary to remove all ice in the gutters or the ice dam itself because if you remove the snow from the roof, the ice will then melt as the temperature rises.
