What Are Ice Dams?

 Daryl Gentry

 January 5, 2023


Key Takeaways About Ice Dams:

  • Icicles are a menace. The only thing they are good for is as a cover, so your mom won't know you almost shot your eye out with your Red Rider BB Gun. The other thing these stalactites are a sign of are ice dams.
  • Ice dams can cause extensive water damage to your roof and the surfaces under it.
  • The professionals at TK Roofing And Gutters can help prevent ice dams and keep your roof safe in the winter.

When most people picture a winter wonderland, they might picture a snowy landscape with a cozy fireplace, smoke billowing from the chimney, and the winter moonlight reflecting off of the icicles hanging off the eaves.

While icicles might be a part of a picturesque winter wonderland, they could be a signal of a hazard to your roof and your home.

Those icicles glistening in the winter sun might be a sign of ice dams.

What are Ice Dams?

Ice dams are a ridge of ice on the edge of your roof that stops the melting snow and ice from draining correctly off your roof.

Before the next snow, homeowners should take steps to stop ice dams and keep their roofs in good shape through the cold winter season.


What Causes Ice Dams?

An ice dam is a ridge of ice that forms when excess snow melts on a warmer part of your roof surface and flows down to the colder eave overhang and refreezes.

As the ice builds up, it forms a blockage that stops more melted snow from running off the roof edge.

That blockage causes the ice to build up under your shingles, where it will eventually melt into the roof sheathing and leak into the attic.

It soaks the insulation and can leak through the ceiling and into your living space.

Large ice dams can have considerable weight to them, so aside from the water damage they cause, they can damage your gutters or even put people below in danger.

When temperatures in the space between the underside of the roof deck and the attic are warmer than the air outside, ice dams are allowed to form.

The warm air under the surface of the roof heats the shingles, melting the snow and causing water to flow down the roofline.

From there, it gets stuck and freezes.

Snow is an insulator, so ice dams are made or get worse after heavy snow.

Warm air gets trapped under the snow layer, so it melts.

Preventing ice dams is a simple matter of thermal physics.

When the air in the attic can stay as cold as the air outside, the rooftop snow won't melt, so there won't be enough water to form ice dams.

Recognizing Ice Dam Damage On Your Roof

If you're worried about ice dams accumulating on your roof during the winter, you should know the signs of water leaks so you can evaluate any damage.

To get a good idea of how bad the damage is, you might need to have a roofing contractor come in and give you an estimate.

Here are some do-it-yourself ideas to try in the meantime:

Take Pictures

Take a few photos of the exterior of your house. These pictures can be used as a reference point so you can investigate signs of water damage on the inside.

If you think you know the location of an ice dam on your roof, take a look at your ceilings and walls for stains near where the ice dam is.

Keep An Eye On Your Attic

Climb into your attic and look for drips and water stains on the rafters, attic floor, and underlayment of the roof.

It can be helpful to mark these spots so that you can find them again easily.

Inspect Your Chimney

As you prepare your chimney for Santa's arrival, look for any signs of ice forming around the base where it meets your roof.

If the flashing is loose or isn't sealed well, ice and melting water can also cause damage here.

When you're in your attic, see if you can determine how heat is escaping around your chimney. If you can see daylight through that seal, you must fix it immediately.

How To Prevent Ice Dams

Keeping your roof cold is the main way to stop ice dams from forming. If your roof is cold, snow won't melt, and ice ridges won't form.

Even in the dead of winter, keeping your roof cold isn't as easy as it seems.

Fortunately, we have some tips to help you stop ice dams.

Attic insulation keeps the warm air in your house and out of your attic.

A proper ventilation system keeps your attic close to the outside temperature. If the snow doesn't melt, ice dams shouldn't form.

To prevent ice dams from forming on your roof and roof valleys in the first place, you need a proper ventilation system.

If necessary, improve ventilation in your attic, add insulation, and fix air leakage.

These aren't quick fixes, and they will take some work and, most likely, the help of a professional roofer.

In the long run, though, you won't have any ice dams on your roof, and your home will also use less energy. It's a win-win situation.

Here are ten steps you can use to avoid ice dams:

  1. Improve ventilation. The first step is to keep cold air moving under the roof. Your roof ridge and soffit vents should do this for you, but they'll need to be inspected by a professional every so often. A roofer may need to install baffles to improve the flow and give the air a clear path.
  2. Cap the hatch to your attic. Anyone without a sealed attic hatch needs a weather-stripping cap to keep the heat in your house and out of the attic. The last thing you want is the warm air from your house traveling into your attic. That air will melt snow on the roof, which could cause the snow to freeze and make ice dams.
  3. Check out your exhaust systems.  Your house will likely have exhaust vents in the bathroom, kitchen, and from dryers. These vents lead outside through the walls or roof. If they're vented to the soffit, you'll have to change that to get rid of ice dams for good.
  4. Inspect your insulation. Take a look and see if you need more insulation in your attic. Keeping attic insulation at the proper depth helps keep your home warmer and uses less energy. It also keeps the cool air in the attic.
  5. Install new chimney flashing. Most chimneys have a metal strip that keeps water from getting into the house from the chimney. If yours doesn't, add one and seal any holes where ice, water, or cold wind could get in. Be sure to use fire-safe products.
  6. Caulk leaks. Anywhere that electrical cables, vent pipes, satellite dishes, or other things penetrate the roof, gaps and air leaks can happen. Use a fire-stop sealant to caulk these spots to keep as much air out as possible.
  7. Check the ducts. Your ductsshould be sealed and insulated properly. For older houses, inspect the heating ducts just to be sure they aren't feeding heat into the attic.
  8. Check out your lights. If you have can lights or any other type of light fixture that isn't sealed, heat is getting into your attic. You could also put your home at risk of catching fire. Change these lights to IC-rated fixtures, which allow insulation to touch them directly to make them safer.
  9. Add an ice-and-water barrier. When you replace your roof, you should add an ice-and-water barrier. This is a great safety measure that's now required in many places. An ice-and-water barrier is expensive if you aren't doing a complete roof replacement, but it's the perfect time to do so if you are.
  10. Take care of your roof. Keeping your roof in pristine condition is one of the best ways to stop ice dams. You should also be sure you always have enough insulation to keep the warm air from escaping.


What If You've Noticed An Ice Dam?

Ice dams aren't always a problem in and of themselves.

Most of the damage is caused by leaks.

If you don't notice any signs that water is leaking in due to an ice dam, you may not have to do anything.

Then, use the prevention methods we discussed earlier when it gets warmer.

The prevention of ice dams begins in the spring, summer, and fall. Once winter hits, there isn't much that can be done to get rid of ice dams.

If you notice an ice dam or the leaks it is causing, the best thing you can do is have a roofing company inspect your roof when the weather breaks in the spring.

You should take pictures and document where the ice dams were, so your roofer can inspect those areas. 

There are products like ice rakes that are supposed to help you remove ice dams and snow off your roof. However, if you decide to use it to break up the ice, you risk damaging your shingles.


Contact TK Roofing And Gutters

Making sure you don't get ice dams in the winter is essential to home maintenance.

Your roof protects your home from the elements, so keeping it in good shape will save you a lot of trouble and stress.

Always ask for help from a professional roofer in your area if you aren't sure you can take the necessary steps to prevent ice dams.

TK Roofing and Gutters has been helping people like you keep your roof winter ready for years.

Call TK Roofing and Gutters today if you need a professional roof inspection, help with roof repairs, or a complete roof replacement.

We can look at your roof and give you a FREE ESTIMATE to ensure it's in good shape for the winter months.

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