By Amy DeYoung
Updated Oct 28, 2022
Icicles may make your home look like a winter wonderland, but the buildup of ice and water can cause ice dams, which are thick ridges of solid ice built up on the eaves of your house. Ice dams can cause torn gutters, shingles to fall from your roof, and water to back up into your home, possibly causing leaks and damage to your roof.
Fortunately, there are many ways to prevent ice dams from forming. To help, we’re sharing our top tips for preventing ice dams and keeping your home safe in winter.
Icicles and ice dams form when snow melts, and the water runs down your roof but refreezes at the edge of the roof. This phenomenon happens when your roof is warmer than 32°F, which is warm enough to melt snow, but the outside temperature refreezes the water at the roof’s edge. Often, ice dams form when you have an overly warm attic with air leaks allowing heat to seep through outside.
Ice dams are hazardous because the buildup of ice can put excessive amounts of weight on your gutters, leading to them falling or buckling. This occurrence can lead to shingles loosening and dropping off your roof, exposing your home to the elements and possible water leaks. Gutter repair can be costly, with aluminum gutter replacement costing $3,000 for the average American home.
If water pours back into your home, you could also be looking at expensive water damage repairs, such as peeling paint, stained walls, sagging ceilings, and warped floors. In addition, any insulation in your attic may grow mold or mildew from the water. On average, water damage costs between $2,800 and $3,300 to repair, making this an expensive mistake.
In short, you want to do whatever you can to prevent ice dam buildup on your roof to avoid expensive repairs and smelly mold in your home.
If you already have icicles and ice dams on your roof, take immediate action by using a long-handled aluminum roof rake to drag ice and snow from your roof. Always use a roof rake, which typically has wheels. Otherwise, you risk damaging your roof.
The rake will quickly pull ice and snow off the roof, immediately improving the situation without harming your roof shingles.
Heated cables are an excellent preventative measure against ice dams. To stop ice buildup, you can attach heated cables along the roof’s edge, ideally in a zigzag pattern.
The heated cables keep your roof’s temperature equalized and heat it from the outside rather than blowing in warm air from the inside. Make sure you install heated cables before heavy rain and snow hit your area for this method to be effective.
Another way to prevent ice dams is by blowing in cold air from the inside of your attic. Use a box fan in your attic and aim the fan at your roof’s underside wherever water is actively leaking. The cold air will freeze the leaking water in a few minutes, preventing additional damage.
After the leak has frozen, take further action to treat the problem. For example, rake your roof with a snow rake to remove built-up snow and ice dams. Later, install heated cables to prevent ice dams from forming in the first place.
If water damage and leaks have already occurred, don’t hesitate to contact a roofing professional to have your roof repaired and assessed for weak spots.
If your roof has a recurring problem with icicle and ice dam formation, assess your attic insulation level.
Check that your attic is up to code and properly insulated. Fiberglass and blown-in cellulose are great options for insulating your attic and sealing air leaks because they can tightly fit around joists, obstructions, and rafters without leaving any gaps.
You’ll want to check for air leaks. If you find attic air leaks, have these filled to prevent warm airflow from escaping your home because most homes experience heat loss through the ceiling of their attic.
Start by looking for unblocked walls, cracks around light fixtures, gaps in drywall, and cracks around plumping pipes, access hatches, chimneys, and more.
Unfortunately, air leakage can be tricky to stop, but a thorough inspection and work with foam and caulk can resolve the issue. Be sure to wear a dust mask and protective clothing, like long pants and a long-sleeved shirt, while working near insulation, which is known to cause skin irritation. Use foam and caulk to fill in any cracks and gaps. This process will not only help with ice dam prevention, but you’ll save money on your energy bills.
This odd but effective DIY solution is a favorite among homeowners because of its affordability. Simply take a leg of old pantyhose and fill it with calcium chloride ice melter, then lay the pantyhose on top of the roof so that it’s on top of the ice dams and overhang on the gutters.
If you can’t safely reach the roof, use a long-handed snow rake to push the pantyhose into position. As the calcium chloride melts ice and heavy snow, your roof will have a channel for water to stream off the roof surface safely.
Attic ventilation draws in cold outdoor air and flushes warm air outside, resulting in a cool attic and warmer roof. Soffit or roof vents can improve your attic’s ventilation system and help with ice dam problems by preventing your roof from warming up too much, which can cause ice dams to form.
Examine any current vents on your roof and check to see what size they are. Then, purchase additional vents in the same size and install them on the underside of the overhang, otherwise known as the soffit, in every other space in the rafter. You can also install them continuously along the peak of your roof.
If you have a short roof ridge, consider adding square-shaped ridge vents near the peak so that the ventilating area is nearly equal to the soffit vent area.
If you have an existing ice dam, use a steamer to melt the ice. Steamers are similar to pressure washers, but the water is hot enough to melt snow and ice without damaging the roof deck and shingles.
A steamer is an excellent alternative to using a hatchet or ice pick, which can cause shingle penetration and permanent damage.
If you already have ice dams formed on your roof, it’s imperative that you take immediate action to remove ice dams to protect your roof and gutters. After completing your ice dam removal, take preventative measures to protect your roof from ice dams and make it easier for your roof to melt ice. Consider purchasing roof-safe rock salt to help prevent ice and install permanent solutions, like soffit vents and heating cables, to protect your roof and gutters from severe damage from heavy snowfall.
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