Ice Dam Formation and How Insulation Prevents It

While picturesque, ice dams are not welcome sights. They can cause water damage to your roof and attic. Worse, the sharp icicles hanging off an ice dam are safety hazards. If any of them fall or if the ice dam itself falls, they may cause serious injury and even death.

Read on to learn about how ice dams form, what you can do about them, and how you can prevent them with proper insulation.

Ice Dam Formation Process

Snow on the roof melts, refreezes at the eaves or gutter, and forms ice dams due to temperature differences across the roof. This means that warm air is coming from within the house and up into the attic, heating the underside of the roof.

However, the heat doesn’t reach the eaves or gutter, so the water freezes there. The ice accumulates, forming a dam that causes melt water from the warm roof to back up. The melt water then starts flowing under the shingles and into the house.

Damage to Your Home

If ice dams form on your roof, it can tear gutters off and loosen shingles. The backed up water can seep into your house, causing water and moisture damage.

It can lead to stained and sagging ceilings, peeling paint, a warped floor, and soggy attic insulation. This also provides habitats for mold and mildew growth. Additionally, your home will lose its resale value.

The ice dam may melt and come loose when the weather warms. It can fall, possibly taking shingles and the gutter with it, and injuring anyone below.

Signs of Ice Dam Formation

There are numerous warning signs of ice dam formation:

  • Presence of ice on the gutters or on the lower edge of the roof
  • Ice around the soffit vents or coming through the vents themselves
  • Icicles along the roof’s edge
  • Ice or melt water on the siding

As soon as you see any of these signs, take measures to prevent ice dams. You may try using heat cables. These are placed along the edges of the roof and will heat it so that melt water doesn’t refreeze and form a dam.

Some may find the heat cables unattractive. Also, they can only be used to prevent ice dams, not remove existing ones. If you choose to use this method, install them early.

Dealing with Existing Ice Dams

Once ice dams have formed, don’t try to remove them yourself. You will be putting yourself at risk of injury. Instead hire a professional to ensure ice dams are removed safely.

If the ice dams are already causing damage to your home, there are a few things you can do to mitigate it. Keep in mind that these are only temporary solutions.

What not to do

Let’s start off by talking about what not to do when you have an ice dam.

You might be tempted to get a hammer, chisel, or some other tool to hack at the ice and break it off. However, this can break your roofing. Don’t use salt either. It’s highly corrosive and may damage your roofing, siding, gutters, and downspouts.

Freeze leaks with cold air

If the ice dam causes a leak in your attic, you can stop it by blowing cold air onto it. Bring a fan into the attic and aim it at where the leak is from beneath the roof to freeze it. This will help prevent further damage to your home.

Rake the snow

You should always remove excess snow from your roof after a heavy snowfall, but it becomes even more important to do so when you have an ice dam. Use a long-handled roof rake to safely scrape snow off your roof from the ground. This will help decrease the amount of melt water buildup.

Never try to remove snow by climbing up as you’ll be in danger of slipping and falling. You don’t need to reach your whole roof either, just whatever part of it you can with the rake.

De-icing methods

You can try using de-icing methods to melt the ice dam or create a gap in it. Check your local hardware stores for de-icing products such as calcium magnesium acetate. They’re sold as tablets or crystals that can be spread over affected areas to safely melt the dam.

Another method is to fill a discarded pantyhose or something similar with calcium chloride ice melter. You then lay this across the ice dam, hanging over the edge. This creates a gap in the ice dam through which the water can drain.

Attic insulation as a permanent solution

attic insulation

The best way to prevent ice dams from forming in the first place is to keep the entire roof at the same temperature. You do this by insulating your attic. Proper insulation will keep heat within your home from escaping and warming your roof.

It’s possible to insulate your attic yourself, but only if you’re highly experienced. Installing insulation is a job for professionals. Unless you have several years of DIY experience, it is highly advisable you hire one.

That’s why you need A+ Insulation’s attic insulation installation service. We’ll keep your home safe from ice dams and other damage caused by poor insulation.

Other solutions to consider

In addition to attic insulation, there are several other ways you can prevent heat from reaching your roof to minimize the risk of ice damming.

Attic ventilation

Along with poor attic insulation, poor ventilation is one of the two main causes of uneven roof temperatures.

By allowing the cold winter air to flow through your attic, it keeps your roof cold and prevents ice from forming a dam. Proper ventilation also reduces moisture in the attic, preventing mold, mildew, and rot.

Vapor barrier

Your attic’s insulation should have a vapor barrier that keeps warm, moist air from entering the attic. There should be only one, between the ceiling and the insulation.

If the vapor barrier is above the insulation or if there is more than one, moisture can get trapped, causing the insulation to get wet. This can lead to mold growth. If there’s no vapor barrier, heat and moisture will enter the attic.

A+ Insulation will correct this problem for you should we find it.

Seal the attic hatch

Your attic hatch is a huge opening through which heat can enter your attic. Air seal the trim with caulk and foam sealant depending on the size of the gap. Air seal the hatch perimeter with compression bulb weatherstrip. Finally, insulate the hatch itself with foam.

Ensure all exhausts lead outside

If your exhausts are improperly installed, they can bring heat to your attic. All ducts should lead hot air outside, either through the roof or the walls. They should never go through the soffit as they will heat the roof.

Use sealed can lights

As recessed lights are installed directly into the ceiling, they can create pathways for heat to travel into the attic. Unfortunately, they can’t be insulated. Use sealed IC-rated lighting fixtures instead and cover them with insulation.

Insulate ducts

By installing thermal insulation on your ducts, you minimize energy loss. Less heat will escape from the ducts and into your attic. Use fiber-reinforced mastic for the joints and cover everything with R-5 or R-6 foil-faced fiberglass insulation.

Caulk penetrations

You can further insulate your attic by sealing electrical penetrations and vent pipes with a fire-stop sealant. This blocks off small passages through which heat can travel.

Clean your gutters

During the fall, gutters are often clogged by fallen leaves and branches. Make sure to clean them before winter comes around. Otherwise, water will flow through them more slowly, giving them more time to freeze.

Additional benefits

Investing in attic insulation and ventilation might seem like too much just to deal with ice dams. However, they also come with various long-term benefits, and you’ll be glad to have them the whole year, not just during winter.

Utility bill savings

With better insulation, you won’t need to spend as much on heating and cooling to maintain comfortable temperatures. Insulating your attic can save you up to 30% on energy bills. This also saves you on HVAC system maintenance costs since there’s less wear and tear on them.

Safer home structure

Insulating your attic protects your home from heat and moisture damage. It will protect walls from erosion, shingles from swelling and cracking, and plywood from softening and rotting. It also eliminates cool, moist areas where mold and mildew can grow.

Better indoor comfort and health

Homes are susceptible to sudden temperature fluctuations if they’re not properly insulated, even if they have the best heating and cooling systems. With proper insulation, you’ll ensure comfort throughout the whole day, even as temperatures lower during the night and early morning.

Insulation also prevents pollutants from entering through air leaks. This improves air quality within your home, helping you stay healthy and avoid diseases.

Let us insulate your attic

A+ Insulation provides high-quality insulation installations. We provide upfront, on-the-spot quotes and are as minimally invasive as possible during installations so you experience few disruptions.

If you want the added benefit of soundproofing your home, check out A+ Insulation’s best soundproofing insulation.

Contact us to talk to one of our insulation experts. Call us at (913) 281-2250 if you live in Kansas or (816) 265-1947 if you live in Missouri. You can also fill out our contact form.