Just in case you needed one more reason to get tired of a long, cold winter, now your roof is ringed with ice dams.
“How could this happen?” you ask. Well… it’s simple, really. Your attic is poorly insulated and/or poorly ventilated. Perhaps at one point it was all constructed perfectly, but the R-value (ability to insulate) of insulation decreases over time and required a periodic “booster”. Additionally, ventilation can be affected by clogging, obstruction, or home maintenance / improvement that unknowingly affects air flow.
Because of this, the hot air in your home is able to travel upward through the ceilings, to the attic, and then to the roof. Anytime the air inside your attic is warmer than the air on the roof, a melting effect will occur and the snow on the outside of the melts and trickles down until it hits the eves.
Since the eves are not above the attic floor, they stay cold, and the water freezes on them. As this process continues, ice builds up, forms a ridge, and builds back to the point where the roof becomes warm again. Then comes the part where water builds up behind the ridge (read: the ice dam you need to get rid of), gets forced up between the shingles, and starts raining down on your parade, attic, and indoor ceilings. It’ll ruin your house and your day.
Ice dams don’t have to happen, but the way to get rid of them is not to chip away at the ice. Rather, the most effect technique is to solve the problem of your roof getting warm in the first place.
Damage Caused by Ice Dams
In extreme cases – which I have personally had more than once – an ice dam can require you to repair and repaint walls inside the house. It is a bad feeling to know that it can happen again, the next time conditions are right!
Ice dams are bad news and need to be prevented.
Best Ways to Remove Ice Dams
If water is coming in, blow some cold on it.
This is a stop-gap solution, but might help. With ice dams, people often don’t realize there’s a problem until it’s too late. If water is coming in, get up to the attic with a box fan or two, find out where the water is coming in, and position the box fan to blow air onto that spot. This might cool the area enough to refreeze the water and stop the flow.
Again, it is a stopgap effort and not a permanent solution, but give it a try.
Cut a channel for water to escape the ice dam.
If you have help, this should be done simultaneously with the first step. If not, keep this at #2. Find yourself a ladder, an ice pick, and some type of ice melt.
This is most safely done if you are working on a roof or eave that is near the ground. Get up, locate the ice dam, and start chipping a channel from the edge of the ice dam straight back to the water. Since you don’t want to damage your roof, stop chipping when there’s about 2” of ice left above the shingles and dump a bunch of your ice melt into the channel to finish the job.
This does not address the root cause of the ice dam, but if your home is one that only gets a dam under perfect conditions — once every few winters — it might be good enough.
Be safe!! People get hurt trying to fix ice dams.
Clear the snow from your roof.
If you don’t have one, go to your favorite tool store and buy a roof rake. A roof rake can reduce the changes of major ice dam damage, although it does not address the root cause of the ice dams.
Roof rakes allow you to safely and easily remove snow from your roof from the ground. This does a couple things: because snow insulates your roof, removing it allows the temperature of your attic/roof to drop to below freezing and stop the melting. It also removes the water’s source. To avoid damaging your roof, always pull the rake and snow straight down; never sideways.
Find a good roof rake here, on Amazon. We like this one because it is adjustable and telescoping, so you can make it as short or as long as you need.
Remove the rest of your ice dam with water.
There are two particularly effective ways to do this yourself. If you live in a one story home, feed one end of a garden hose through a window, and into your house. Attach that end to a faucet and attach the other end to a garden rake or some other such implement so that it points back at you. Now you can use your magical hose-wand to blast the ice with water, from the ground, to melt it off. This is a long, albeit effective, process. You can use hot water, and it is faster… until you run out. It’s also more expensive. Cold tap water will work just fine.
Again, be careful! Do not go on your roof unless you have proper equipment and know what you are doing!
Melt ice dams with calcium chloride.
While I don’t have anything against playing with the hose, I do prefer this method over the previous. Whether your home has one story or two, get a ladder, a container of calcium chloride ice melt, and a scoop. Lean your ladder against the house, get someone to hold said ladder, get up there and start scooping ice melt and pouring it along the back wall of the ice dam. This will create a reservoir of slushy, briney, ice melty water that will continue to eat away at the dam while helping to clear your gutters and downspouts. We’d recommend a big bucket of Calcium Chloride Snow & Ice melt pellets, which you can get from Amazon.
Be careful with calcium chloride, though, because it can stain your shingles. You need to use it as directed on the bag.
Natural/Chemical-free Ice Dam Removal
Ice Melting Cables.
While these are intended to be, and are quite effective as a preventative, some folks have used ice melting cables for getting rid of ice dams. The cables are laid on top of the ice dams and allowed to do their thing. It’s a slow process, but if the ice dams aren’t damaging anything, they’re not a bad option. They can be used both on the roof and in the gutters.
Our experience is that they are not perfect, but will often create some warmer channels to allow water to escape off the roof. If you can re-insulate and actually fix the problem, that is preferable.
We once had a house that, because of the roof and attic design, was truly unable to be ventilated in a way to prevent ice dams. For that house, roof cables were the answer.
We suggest calling a roofing company (they are often looking for winter projects) to install the cables properly.
Give it time.
If there’s no damage being caused, you probably already have ice and water barrier on your roof. This means you may be able to wait for the ice dam to melt on its own. Once the attic gets warms up a bit, get up there and get it prepared for next year. No point in pushing your luck.
Hire some pros.
Professionals usually just use big ol’ steamers. What’s more natural than water vapor? However, when looking into professionals, make certain they use steamers and not pressure hoses. Pressure hoses can damage shingles. As well, be sure you look for professionals who are insured. Nothing makes ice dams more of a problem than roof damage that is caused by workers who aren’t insured and bonded.
We cannot stress this enough: Play it safe on roofs.
Many of the things we suggest above are dangerous, especially for people who are not experienced on roofs. Couple that with the fact that you are doing these tasks in the winter when there is snow and ice, and you need to really play it safe.
If you have any doubt in your mind about safety, just call the professionals. All it takes is one slip and your life could change through permanent injury or worse.
How to Avoid Future Ice Dams
- Clear gutters in fall
- Put flashing up around the chimney where it enters the attic
- Seal around wires entering the attic with fire-stop sealant
- Make sure all vents vent to outside
- Make sure soffit vents are clear
- Add roof vents to make 1 sq. ft. of venting for every 150 sq. ft. of attic floor
- Insulate the attic hatch
- Consider hiring an insulation company to do an audit of your attic. They often do this with a cool infrared camera. It will show where the attic might be too warm or too cold, and causing the dams.
- Increase attic floor insulation (R-45+ for MN) (if you’ve not started with this, you can find rolls on Amazon