Ice dams aren’t great for your home—here’s how to prevent them
Save yourself some money and a headache
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When the winter storm warning rolls in, be prepared for the ice and snow that come with it. During nor'easters your roof is vulnerable to ice dams, which can lead to expensive headaches, like leaks and damage to your home and belongings. The best way to protect your home is to be proactive about ice dam prevention.
The best way to deal with ice dams is to prevent them from ever forming. Like any winter problem from frozen pipes to a rutted driveway, planning, maintenance, upgrades, and some elbow grease works wonders.
If it’s too late for ice dam prevention, there are some ways to get rid of ice dams using roof melt, and roof rakes.
Whatever solutions you decide to try, just make sure that you are careful—winter weather conditions and ladders do not mix well. Here’s what you need for ice dam prevention.
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 edges or in the valleys, when melting water isn’t able to drain away and refreezes. They can 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 leads to water damage of 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 before the next freeze warning.
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 check in on your attic insulation. 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 save you money.
If you’re losing enough heat into your attic that it melts snow on the 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 freeze warning, 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 guards like the A-M aluminum guards that can keep your gutters clear. (See top gutter resources.)
4. Install roof heating cables
Roof heating cables like this set from Prime Wire & Cable 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.