Ask Wirecutter: How Do I Keep the Gutters Clear of Ice and Leaves?

We live in Chicago and just went through some snow and the polar vortex. After the snow we discovered that we may not have enough insulation in our attic because our roof warmed and melted snow, which hit our frozen gutters and caused an ice dam. One roofer suggested we get a gutter heater, which I never knew existed until that day. I said yes out of fear of any damage ahead of the polar vortex. However, I have no idea if I made the right decision. Are gutter heaters even necessary? Should I have just waited for it to warm up and melt off? Should I add more insulation in my attic? Would love to hear some viewpoints on this. I know ultimately each homeowner situation is unique, but I’d love to have a little more clarity on this. —Albert H., Chicago

My gutters were knocked around by the heavy snow we’ve had. Should I get snow guards for the roof? Or something like gutter heat by Frost King? Or just repair the gutters when the snow weighs them down? What is the most cost efficient for the long term? —Maya W., Washington, DC

Hello Albert and Maya,

Okay, I have a long history of living in ancient, poorly insulated homes so I have a long and storied history with ice dams. I get ice dams almost immediately after a snowfall. It’s bananas. I have no insulation in my walls. It’s almost like my house was built in Revolutionary times or something. (It was.)

They happen due to poor attic insulation or inadequate ventilation. In most cases, you want the underside of your roof to be the same temperature as the outside air. If it’s not, the heat from your home melts the snow on your roof (while it’s still below 32 degrees outside) and the water runs down to your eave, which is not warm in any way, and freezes. Little by little this frozen mass builds up until it makes a bowl that traps water against the roof. Depending on how your roof is constructed this can back water up under your shingles and into your home. Once that happens you can be looking at some seriously expensive repairs. Once it gets into your walls and gets your insulation wet, it lowers the R value of your insulation and you can get mold.

There are a few ways to stop these from happening. The least expensive way, which takes a little effort, is to use a roof rake to clear snow from your roof after each snow. Our recommended roof rake extends to 17 feet, so you can use that as a guideline. Ideally you want to get all of the snow off, but if you can’t do that, at least remove it from the eaves (and go as far back as you can) and the valleys, if you have any and you can reach them. With this limited approach there is still snow up there that can melt and run down, but at least this is a start. I roof rake after every snowstorm. It’s a hassle, but worth it.

Heat cables, like the Frost King, 60-foot Electric Cable Kit, have good reviews at Home Depot, although many are from people who have installed them and not used them long-term. On the good side, they melt snow and create channels for water to escape the roof, but on the bad side, they use a decent amount of electricity and they can fail (I’ve seen them completely encased in ice). Also, if you lose power during the snowstorm, you’re out of luck. Just putting them in your gutter probably won’t help much, because, if you recall, the water is freezing at the eave too, so you’ll likely need them on the roof as well.

If you have a house prone to ice dams, I’ve also found it very helpful to have some calcium chloride on hand, both loose and in puck format. You can toss the pucks up on the roof and they melt, presumably dissolving into the water, running down to the ice dam and melting that. I’ve found that it’s not that simple and they work best when placed directly on the ice dam. Calcium chloride is corrosive (and there are reports of it staining roofs), so I don’t like just tossing them up there wherever. I prefer to be a little more specific in my placement with them directly on, or right behind, the ice dam. It’s something to have on hand in case things get out of control (or if your heat cable malfunctions mid-storm). I don’t recommend it as your primary defense against ice dams.

Likely the most expensive and invasive (yet comprehensive) solution is to redo the insulation in your attic or add some ventilation. There are so many variables here that it’s difficult to make any strong recommendations.

As for snow guards, I've only seen them on slate roofs, where when the snow slides off, it all slides off at once. (I have a slate roof and when snow lets go, it sounds like a freight train and is pretty dangerous to anyone below.) To have guards you really need to have some bulletproof attic insulation or trust in your roof construction, because the guards just hold all of that meltable snow up there on your roof. My general opinion is to just get the snow off the roof as fast as possible (if your house is prone to ice dams), whether it’s done via roof raking or letting it slide off on its own.

But if the snow is tearing your gutters off, snow guards may be worth considering. You should also look at how high your gutters are hung. Some roofing contractors hang gutters lower on slate and metal roofs so the sliding snow (theoretically) goes over the gutter as it heads to the ground (as shown in this image from Inspectapedia). I’d recommend talking to a couple roofing contractors to get some options for your specific scenario.

For more reading on the topic, Fine Homebuilding has a detailed explanation of how ice dams form and what to do to prevent them. A similar story from This Old House echoes the Fine Homebuilding advice on long-term fixes for ice dams.

—Doug Mahoney, senior staff writer

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My house has standard rain gutters. The house needs repainting so this would be a good time to replace the gutters, which are 46 years old. My biggest problem is pine needles falling through the mesh on the gutters. Would LeafGuard rain gutters alleviate this situation? Thanks. —H., Houston

LeafGuard and its various similar competitors claim that surface tension gutters cause water to flow over the curved surface into the gutter while keeping leaves out. These things are very expensive. Do they actually work?
—Richard B., Cleveland

We polled our homeowners’ Slack channel to see if anyone had experience with covered gutters. One of our editors in Portland, Oregon, bought a house with multiple 100-foot-tall leafy trees on the property about three years ago. It came with covered gutters, and he is happy with them, having never had to clean them.

However, reviews from experts seem to be less enthusiastic. Though we haven’t tested LeafGuard ourselves, we looked at some of the testing done by other people (testing from Family Handyman, videos from EnduringCharm and Roofing Insights, and an even-handed overview from Inspectapedia, a site for home inspectors). We agree with Inspectapedia’s basic conclusion: Gutter screens and covers can be good for “high, hard to access roofs with nearby trees.” It seems that otherwise it may make more sense to skip them and just deal with frequent cleaning. (Regarding pine needles in particular, EnduringCharm’s video says at 0:40, “If there’s big trees nearby, or certain types of trees, like pine needles and things like that can get jammed in here, especially when there’s small holes and things like that …”)

One thing that comes up a lot in the criticisms is that the screens themselves need maintenance and cleaning—just not as often. So you’re still either getting on a ladder or paying someone else to do it (and this is after you’ve shelled out the money to install the gutter covers). For someone cleaning their own gutters, leaf blowers work great. Downspout screens are an inexpensive way to deal with things as well if you want something quick and easy.

—Harry Sawyers, senior editor