Important Facts about Ice Dams and How to Prevent This Roofing Problem


Wintertime signals the start of many problems that homeowners may have to contend with. One of these is the formation of ice dams.

An ice dam begins forming when ice and snow start to accumulate on rooftops. After freezing into a solid mass, the ice dam allows melted water to gather behind it. This water will in turn trickle down roof shingles and into the house, causing excessive damage to ceilings, walls and floors.

Moreover, ice dams also contribute to house damage due to their weight. They put pressure on gutters and downspouts, causing them to move away from the house along with the accompanying fascia boards.  Other serious problems caused by ice dams are cracked plaster ceilings, mildewed walls, peeling paint, damp carpets and buckled wood floors. Minor issues created by ice dams and the accompanying water damage are wet insulation, rusted joists and formation of mold. Ice dam prevention is therefore essential so as to avoid further damage and extensive repair costs.

Ice Dam Damage

From 2002-2007, water damage and freezing was the second largest percentage of homeowner claims according to the Insurance Information Institute. These statistics certainly make it clear that prevention of ice dam related damage should be a priority for homeowners.

Ice Dam Formation

As heat issues from a house and rises upwards, it causes accumulated snow on the roof to start melting. This melted water will transfer itself from the uppermost surfaces of the house towards the bottom, thereby reaching the eave line and gutter. Once outside, this water will refreeze. This new formation of ice will in turn expand, blocking the flow of further snow melt. The water that continues to melt on the rooftop will keep on accumulating behind this barrier. Since it will be situated over a warmer part of the roof, it will not freeze again and thus maintain the ‘pool’ behind the ice dam.

The three requisites for ice dam formation are therefore roof snow buildup, subfreezing temperatures and home heat loss.  The greater the snow fall, the larger will be the heat loss. Similarly, the longer temperatures remain below zero degrees, the greater is the chance that ice dams will form.

Prevention Of Ice Dam Formation

Homeowners need to take extra initiative to safeguard the exterior of their house from adverse weather conditions. In order to minimize heat loss, they will need to prevent internal heat from reaching the roof. If this is managed effectively, it will drastically reduce the degree to which snow on the roof would melt. Home owners thus need to have proper insulation in the house walls and roofs. The attic space should also have proper ventilation so that the roof surface is close to external temperatures.

Home owners can ideally insulate the attic floor and use soffit, gable or ridge vents to remove heat. Insulation should also be extended to folding attic stairways and recessed light fixtures. This is to be done thoroughly so that all crevices and nooks that lead from the living space to the attic are properly secured.

Homes that have finished attics may prove to be a little tricky. Heat insulation for these would entail the placing of baffles or tubes between the ceiling insulation and the roof underside. This will permit a sufficient amount of cold air to move from soffit vent to ridge vent.

De-Icing Alternatives

Roof rakes, brooms and other long-handled equipment will normally suffice to remove accumulated snow. However, this cannot be thorough since all areas of the roof cannot be reached. Electrically heated de-icing cables can therefore be used instead of the more mechanical methods. These are installed alongside eave lines to prevent water from freezing, but are only moderately effective. Often, these cables accentuate the problem, causing ice dams to form higher up the roof. They are also expensive to purchase, run, and may cause damage to roof shingles.

Removal of Ice Dams

Home owners can hire a roofing company to remove ice dams. Instead of utilizing typical tools, technicians will use steam to remove ice build-ups. These specialists will thus solve the problem without homeowners having to undertake any dangerous steps, and that too in a cost-effective manner.

Leave a Comment