Long-Term Solutions for Ice Dams [Infographic]

When the heat from the attic combines with the sun’s warmth, the snow, and ice on your roof melt that will eventually form ice dams. The meltwater that flows to the edge of the roof will begin to refreeze. As this process continues, the layer of the ice hanging will get thicker. This will eventually cause a “dam” that will grow as it is fed by the melting snow above it.

The ice dams hanging on your eaves will prevent water from draining off your roof, causing it gets backed up behind underneath the shingles and into your home. It can cause costly damage to your whole roof system, your attic, and even inside the walls of your home.

As ice dams are hazardous and problematic for your home, they should be removed as soon as you notice them. There are a lot of ways to remove ice dams on your roof. However, the key to permanently solving your ice dam problems is to ensure that your roof’s temperature stays consistent with the eaves.

Here are a few tips to prevent ice dams from forming this winter.

Long-Term Solutions for Ice Dams

Ventilate Eaves and Ridge

As ice dams are started by warms spots in the interior, keep your roof cool with proper ventilation. This will allow the warm air and rising moisture from everyday activities to escape before it has the chance to melt the snow and ice on your roof.

There are several ways of improving your ventilation, but the usual recommendation is to create continuous airflow from the soffit to the roof’s peak. A soffit-and-ridge vent system usually requires installing baffles at the lower side of the roof so the airflow would have a clear path from the soffit vents.

Combine these insulation baffles with a ridge vent that allows air flowing up through the baffles a continuous path to outdoor air. Without them, thick insulation can block the air coming in through the soffit vents, eliminating airflow.

In case a soffit-and-ridge vent is not feasible or desirable, another way is to provide the ventilation with soffit or gable vents for intake air. To exhaust air, you can use several conventional roof vents. As a general guide, ventilation systems should provide at least 1 square foot of opening per 150/300 square feet of attic floor.

Cap Attic Hatches

An unsealed attic hatch is a massive opening that is an enormous opening for heat to escape. The heat from the building will seep through poorly-sealed openings and warm the areas directly under the roof.

The pathways through which heated indoor air moves into the attic need to be eliminated. However, you can’t permanently seal attic hatches with foam. Cover your existing hatches by covering them with weather-stripped caps, rubber gaskets, integrated gaskets, or layers of insulation. Hold it together with an aluminum tape to sufficiently insulate these areas.

Add Insulation

A well-insulated attic will help prevent the melt and freeze conditions from occurring, along with proper ventilation. This would prevent heat from entering the living areas through the ceiling, which keeps the attic temperature lower.

While you’re in the attic, check on your attic insulation. Inspecting your attic will also help you find out if it needs replacement or more insulation. Adding more insulation will keep the heat where it belongs. Depending on the insulation materials used, most building codes suggest that homes need 12-14 inches of fiberglass or cellulose insulation.

Flash Around Chimneys

The space around your masonry chimney is one of the leading causes of ice dams. If it is not sealed off or properly insulated, it will make it easier for the warm air to escape. This can contribute to the formation of ice dams on your roof.

Bridge the gap between the framing and the chimney with L-shaped steel flashing. Then, hold these metal sheets in place with a fire-stop caulk. Don’t use canned spray foam or insulation as it is a fire hazard.

Seal and Insulate Ducts

The ducts running through the attic are often poorly insulated and sealed that they often blow hot, moist air all winter. The hotter the air under the shingles, the more likely it is an ice dam will form.  Seal all the seams with duct tape, caulk, insulation, paintable sealant, etc. You could also spread fiber-reinforced mastic on the joints of HVAC ducts and exhaust ducts.

Exhaust to the Outside

Check the exhausts connected to the kitchen, bathroom, or other living areas all lead outside and not to the attic. Problems can occur when the exhaust is not installed correctly and left running for long periods as it can dump the heated air into the attic in the winter. Ensuring that they’re securely attached and sealed can save you from the possibility of ice dams forming.

Install Sealed Can Lights

Recessed lights in many older homes give off great plumes of heat. As a result, they can’t be directly covered with insulation. These lights can throw off enough heat to cause snow-melting problems by themselves. At a minimum, an excellent remedy is to replace old fixtures with sealed “IC” fixtures or compact fluorescent bulbs, which produce far less heat than incandescent.

If this is cost-prohibitive, cover your old-style recessed with site-built rigid-foam insulation boxes made from ¾ inch foil-faced insulation board. This can be bought at some insulation supply shops. Since it can’t be insulated without creating a fire hazard, make the box large enough to leave three inches of air space around the fixture for fire safety.

Place the boxes over each fixture and seal them to the top of the ceiling vapor barrier with standard silicone. Even IC-rated fixtures are seldom airtight and can add plenty of heat to the attic, so we often cover them with insulation boxes as well.

Install heat cables

When all else fails, install heat cables to deal with the ice dams. Heat cables are high-resistant wires mounted on the edge of the roofline and gutters in a zigzag pattern and plug into an outdoor outlet. They provide a constant heat source to the coldest areas of the roof to prevent ice from forming.

At first glance, these wires may look unattractive, but it prevents ice dams by stopping the melting from freezing when it reaches the eaves. Thus, allowing the meltwater to flow harmlessly to the ground. However, you still need to direct the meltwater away by running the heating cable through the downspouts. Otherwise, it will refreeze in the gutters and along the roof edge.

As heat cables run on electricity, you should be aware of the risks of mixing it with water. Make sure to properly follow the manufacturer’s instructions and maintain the heating cable to ensure that it remains safe.

Fahey Roofing + Contracting has the experienced and skilled contractors you need to help you with any necessary roof repairs and roof replacement. We serve various areas in West Virginia and Ohio. Visit our website today at www.faheyroofingcontractors.com or contracts us at (304) 826-1323 for West Virginia or (740) 523-0380 for Ohio to learn more.

Resources:

https://www.alure.com/home-improvements-blog/roofing_tabs/what-is-an-ice-dam-and-how-can-i-prevent-it

http://www.kuhlscontracting.com/wp-content/uploads/journal-of-light-construction.pdf

https://www.thisoldhouse.com/roofing/21017660/how-to-get-rid-of-ice-dams