There are very few situations that put fear into a homeowner like the ice dam. It’s one of those disasters that takes people by surprise. They awaken after a heavy snowstorm, things look fine from the outside, and days later, they’ve got stains spreading on their ceilings or icicles forming the size of baseball bats. Yet, it’s too late to do anything when they notice the problem.
Because ice dams don’t occur from snow. They occur from what happens above the roof – and what most homeowners don’t realize is they’re creating the conditions necessary for them to form.
What Causes Ice Dams (And It’s Not What You Think)
The truth behind how ice dams form is pretty logical. They happen because heat escapes from your home and gets up to the attic and onto the roof. Because the top of the roof is warmer than the edge, snow that exists on top melts and travels downward. Once it reaches the eaves (which are colder), it freezes. As this process continues, it creates a thick layer of ice along the roof edge which acts as a barrier for drainage.
When water is trapped this way, it only has one direction it can go – and that’s underneath shingles into your home. It seeps into the wood decking that secures your roof, your insulation and drywall and any lingering stains you see months down the line could signify mold.
But it’s not just the roof that’s in trouble. Ice weighs in tons (yes, literally, tons) and gutters are not made to withstand such weight. They pull away from homes, sag, and with the additional strain of ice/largest icicles, sometimes come completely ripped off the fascia board.
Prevent Ice Dams By Preventing Roof Heat Escape
The best way to prevent an ice dam from forming is to keep the roof cold. This may sound backwards, but if there’s no heat escaping your home into the attic to warm up the roof surface, snow will not melt at the top and freeze at the ends.
The best solution to achieve this is good insulation in the attic. For older homes – especially – attics hardly have any insulation, meaning it’s easier for heat to escape. Newer homes have become somewhat lax about putting down decent insulation; sometimes there are gaps from poor installation methods. Ideally, you want 12-15 inches of insulation laid down across your attic floor. Be wary of above chimneys and where there are recessed lights and plumbing vents as well as those spots tend to have air holes as heating elements escape.
Additionally, it’s not only good insulation that’s needed but proper ventilation. Air needs to flow through a space in order for temperatures to remain consistent. Your attic should have ridge vents and/or soffit vents/gable vents that actually move air through them. If they are duct taped off or holes are cut into walls and insulation infiltrates them causing blockage, you won’t be able to benefit from that air circulation.
Finally, you need to seal air leaks like crazy. Heat rises. Therefore, when there’s an air leak in your home, it will find its way into the attic if it can. These include places where wires or pipes pierce your ceiling; around your attic hatches and near ceiling light fixtures. A little spray foam or caulk will go a long way.
Clear Gutters Before Winter Even Begins
Clogged gutters are a breeding ground for ice dams. If gutters cannot allow water drainage because they are blocked by leaves and debris accumulated from the fall, there is nowhere for melting snow to go but underneath shingles or create an ice mass at the bottom of the roof.
Completely clean out all gutters in late fall before temperatures drop. Get rid of all leaves, sticks and that weird sludge that forms at the bottom. While you’re at it, make sure downspouts are open – they direct water several feet away from foundations, so they should be clear as well.
If you have an overbearing tree on your property above your roofline, give it a haircut. The branches will not only dump leaves in your gutters but shade parts of your roofs unevenly (creating more reasons for ice dam conditions).
Become a Snow Management Expert
There’s nothing worse than heavy snow piled against one’s foundation or sidewalks or even weighing down lower sections of roofs. The challenge is that by this point, it may be too late – even if melting has set in at roof edges.
You need a realistic plan for snow management around your entire property – it’s not just about rooftops. For sidewalks/driveways/walkways/foundations, snow management tools that allow for practicality as well as usefulness help best. You want something that’s not too heavy or too complicated that you won’t utilize it. An effective cordless snow shovel works well for paths/stairs/near houses where snow tends to pile up near gutters – it’s also better for one’s back (no one wants to deal with a back issue in subzero temperatures!) and doesn’t involve having to work with gas or extensions cords if it’s cold outside.
This step is important because staying on top of snow makes everything easier – it does not give heavy snow debris time to form – and once it’s at say, four or five inches atop the roof – which has already started melting/ice dam forming at roof edges – it’s too late.
When (And How) To Remove Snow From Your Roof
Removing snow sounds great – but this is often when people try going onto their rooftops themselves – and that can be dangerous.
Don’t ever step on a rooftop with snow yourself – it’s slippery and can result in unfortunate accidents.
Instead, for those with single-story homes or low enough roofs accessible from the ground, there are roof rakes – long-handled tools that allow you to pull snow off the edge of the roof without going up onto it. In fact, you don’t even need to clear the entire thing – only a few feet from the bottom where an ice dam commonly forms.
Make sure to pull that snow straight down and away from the home but don’t scrape all the way down to shingles – this can damage them – or leave an inch or two as buffer.
For steep roofs and those with second stories or roofs where a lot of snow has accumulated, call a professional to do ice dam prevention/removal work. Ice dam removal companies use steamers which melt everything away nicely without roofs being damaged better than people can do themselves. They’re expensive but cheaper than roof decking replacement/reconstruction or interior waterproofing work.
What Not To Do (Because People Try These, Anyway)
Don’t chip away an ice dam with an axe or chisel. You’re only going to damage shingles and put holes in your ceiling making leaks even worse.
Don’t throw salt or ice melt on there either – this is corrosive based when it comes to shingles or metal flashing – and not solving anything; just temporarily making a channel of melting that gets filled again.
Don’t throw water on it via pressure washer or hose spray – this adds another layer of ice creating even worse prevention efforts.
The Bottom Line
Ice dams can be preventable – but you have to take care of preventative factors instead of symptoms after the fact. Most preventative results come with good insulation/air quality which keeps homes warm once complete; sealing air gaps is a one-off project and attic elements remain for years until new construction warrants further inspection.
Ice dams? It’s routine maintenance – which isn’t so bad once you settle into a pattern – you’re just trying not to facilitate conditions where ice dams occur in the first place.
If there’s already an ice dam or signs of damage from within roofing materials, it’s better not to wait – those can become exponentially worse over time – and what’s a small stain can become an issue most major if left because water does not take care of itself.