Ice dams aren’t great for your home—here’s how to prevent them
Ice is one of the worst parts of winter, and ice dams forming on your roof can lead to expensive headaches, like costly leaks and damage to your home and belongings.
The best way to deal with ice dams is to prevent them from ever forming. Like any common winter problem, from frozen pipes to a rutted driveway, planning and maintenance, upgrades, and some elbow grease can work wonders. But, if it’s too late for ice dam prevention, there are some ways to get rid of ice dams using roof melt, and roof and snow rakes.
Whatever solutions you decide to try, just make sure that you are careful—snow, ice, and ladders do not mix well.
First things first: What is an ice dam?
An ice dam is a thick layer of ice that forms on your roof, usually along the edge or in valleys, when melting water isn’t able to drain away and refreezes. They can often be seen from the ground, and are typically accompanied by large icicles hanging down from your roof line.
The most common cause of ice dams is an attic that is too warm. When the attic warms up, it melts the snow unevenly, and the resulting water gets trapped and refreezes into a block of ice.
Ice dams themselves aren’t necessarily dangerous. Very rarely, the weight of an ice damn can collapse a section of the roof, but more often, the damage caused by ice dams is in the form of secondary leaks.
When an ice dam forms and the snow melts above it on the roof, the new water gets trapped behind the dam. If left sitting long enough, or if your roof isn’t in good shape, that water can seep in between the shingles and leak into your house. This can lead to water damage to ceilings, walls, and personal belongings.
This damage may or may not be fully or partially covered by your homeowner’s insurance—it’s something that you should check with your insurance company.
5 tips for ice dam prevention
The best way to avoid potential damage from ice dams is to prevent them from forming in the first place. Investing in maintenance or improvements before winter comes can stop this problem before it ever starts.
Depending on your comfort level and the severity of the problem, you can implement ice dam prevention yourself.
1. Make sure your attic is properly insulated
Since ice dams are typically caused by a too-warm attic, the first preventative measure that you can take is to make sure that your attic is properly insulated. The exact amount of insulation that you need depends on your climate, style of home, and insulation type, but your building department can help you decide.
There are also many energy efficiency and insulation companies who can come and measure your insulation to determine if it’s adequate—some states offer great incentive programs like Mass Save in Massachusetts, which can save you money.
If you’re losing enough heat into your attic to be melting the snow on your roof, then properly insulating your attic will likely save you a good amount of money on heating costs.
2. Clean out your ventilation
Another reason that your attic might be warm enough to produce ice dams is a lack of proper ventilation. Without ventilation, the air outdoors can’t cycle through your attic and maintain a consistent temperature.
Different houses have different kinds of ventilation, from gable vents to soffits to ridge vents, but regardless of type, you want to make sure that they are clear of debris, properly installed, and fully functional before winter rolls around.
3. Clean your gutters
Gutters are there to whisk water away from your roof in a controlled fashion. If your gutters are filled with leaves, snow, or other debris, the water may back up and freeze, creating an ice dam.
Each fall, before the first flakes, empty out your gutters of debris.
In the winter, if you know that your home is prone to ice dams, it may be worth climbing up after a heavy snow to remove built-up snow and give the draining water somewhere to go.
There are also many gutter guard products available that can keep your gutters clear.
4. Install roof heating cables
Roof heating cables are simply cables that you lay across the problem areas of your roof or gutters. When you turn them on, they heat up, melting any snow or ice that comes into contact with them and preventing any ice build-up from forming.
Roof heating cables can be a more affordable, temporary fix for ice dams. However, you will still have a remaining underlying issue.
In addition, while properly insulating and ventilating can save you money on your heating bills, running roof heating cables will increase your electric bill. You also have to carefully monitor them to ensure that they don’t overheat or draw unnecessary power.
5. Upgrade you roof
If you are ready to redo your roof, talk to your roofing company about ice dam prevention. Make sure that they use a proper ice and water shield underlayment. Building codes vary, but this should be installed at least on the lowest three feet of the roof, preferably more.
By having a proper underlayment, if an ice dam does form, the water will be less likely to penetrate your roof.
4 tips for removing ice dams
If an ice dam does form on your roof, you don’t need to panic. There are some simple steps that you can take to prevent ice dams from becoming a problem.
Most of these require getting up on a ladder, so make sure that you have a partner to spot you and hold the ladder steady. If you feel at all uncomfortable, hire a professional to take care of it for you.
1. Rake the snow from the roof
Ice dams are typically only damaging if melting snow is able to pool up behind them and seep in under the shingles. In order to prevent this, pick up a roof snow rake—plow-like shovels on very long handles—at any local hardware store.
From the ground, lift the rake up to the roof, and pull the snow down. Just make sure you’re standing far enough back that the snow doesn’t land on you. If you clear at least a few feet above the ice dam, the water will be less likely to pool up and penetrate the shingles.
While you have the rake up there, knock down any icicles that have formed as well. A falling icicle can seriously hurt someone.
If you know that your roof is prone to dams, then raking the roof every time it snows can help prevent ice dams before they form.
2. Use a chemical melting agent
If you do wind up with a problematic ice dam, use calcium chloride, and only calcium chloride, to melt it away. Never use rock salt—it can damage your shingles and ruin any plants that it drips onto below.
Also, don’t just climb up and sprinkle the calcium chloride on your roof. The best application method is to fill an old sock or pantyhose with calcium chloride, tie off the end, and lay it across the ice that you want to melt. The sock prevents the calcium chloride from washing away.
For larger dams, it may be enough to use this method to create channels through the dam for the water to flow.
3. Pound it with a mallet
Sometimes, chemicals either aren’t strong enough or fast enough to solve the problem. In this case, you may need to climb up there and chip away at it.
Always do this with a partner to hold the ladder and watch you for safety.
The best tool to use for this is a mallet. Melt as much of the dam away as you can with calcium chloride, and then use the mallet to clean up the rest. Don’t use something sharp like an axe or a chisel—you can damage your roof and make the problem of leaking that much worse.
And for goodness sake, please do not try to melt the snow with a blowtorch. This is just asking to light your roof on fire.
4. Hire a professional removal service
If you’re not comfortable up on a ladder, or aren’t having success with the above methods, you can always hire a professional to take care of the problem for you.
Many professionals use commercial grade steamers to quickly melt away ice dams, or at least shrink them to manageable chunks. They also can likely give you some ideas to implement for ice dam prevention.
While a pricey option, it’s certainly the safest choice.
Prices were accurate at the time this article was published but may change over time.