What Is an Ice Dam on Your Roof?

What Is an Ice Dam on Your Roof

Vermont winters get cold. We all know this. Because the winters can be long and frigid, homeowners have to deal with challenges and issues that simply don’t exist in the southern states. One of those issues is ice dams. They can wreak havoc on a home. The best way to deal with them is to prevent them in the first place, but that requires a little bit of learning. If you need roof repairs for ice damage, call Total Roofing and Service. In the meantime, here’s some information on the subject.

What Is an Ice Dam?

Ice dams are a formation of ice on the edge of a roof. They build up over time, and when they are large enough, they prevent water from draining off the roof as snow melts. That buildup of water sits on the roof for significant periods of time, and it is likely to create leaks at some point.

Ice dams frequently lead to water damage inside homes. Once water leaks through the outer barrier of the roof, it can damage the substrate, attic, walls, floors, ceilings and everything else below.

What Causes Them to Form?

How does an ice dam come to be? It requires a bit of a perfect storm of conditions. Most of those conditions have to do with temperature differences across the roof.

First, you need snow, which means you need outdoor weather that can sustain snow. When there is snow on the roof, you need a situation where some parts of the roof get above freezing temperatures. This can happen when there are insulation problems or leaks in the roof that let heat out.

Even though some parts of the roof are above freezing temperatures, the lower parts of the roof need to remain below freezing.

When these conditions exist, the snow on the hot part of the roof starts to melt. As it does, it slides down the roof and eventually hits a cold part. At this point, it refreezes. The newly frozen ice sticks in place on the roof. As the conditions persist, more snow slides down the roof and freezes to the building, creating an ice dam. 

The main thing to understand about the ice dam is that its mass causes it to thaw much slower than the snow on the roof. So when the weather warms above freezing, the ice dam melts last, and that’s why snowmelt gets trapped on the roof.

How Can You Prevent Ice Dams?

Considering how much damage ice dams can cause, it helps to take preventative measures.

The key problem with ice dams is that heat leaks out of a portion of the roof. That heat comes from the heater or other sources inside of the house. But leaky insulation or poor roof structure is what allows the ice dam circumstances to occur.

Your best defense is better insulation and a proper seal across the roof. These two things mitigate heat loss through the roof. The end result prevents temperatures from melting snow in limited spots across the roof, and the ice dam never forms.

How Can You Deal With Ice Dams?

If you already have an ice dam, it’s too late for preventative measures. You need intervention. A few things can help you manage the problem. First, remove all the snow from the roof (or as much as you reasonably can). If the roof is clear, the ice dam won’t grow. It’s pretty simple.

Exercise extreme caution if you need to get on the roof to sweep off the snow. Conditions are icy, and that makes the situation much more dangerous than normal. It’s always better to call a professional.

The other thing you can do is create channels in the ice that allow the water to drain. Especially if you already have water building up, you need to create outlets for it. The easiest way to create these channels is with a garden hose. If the snow is melting, then the outdoor air temperature is above freezing, so you should be able to use your hose safely.

Spray a section of the dam with water and melt a channel into it. Start from the bottom and work your way up. Also, do not try to use a hot water source for this task. It can cause the ice to rapidly expand and damage the roof. The cold-but-still-liquid water in the garden hose will work just fine.

Also, keep in mind that this is a temporary solution. Ultimately, you need to manage the heat loss through the roof, and until you do, you need to keep the snow clear as best you can.

When it comes to preventing ice dams and ensuring that your roof is in good shape, it helps to have professionals available. Total Roofing & Service Inc. is here to provide that help. We’ve been doing roof construction and repairs for more than 30 years, and we’ll happily repair your roof too. Contact us today, and we’ll discuss your situation to find the best way to resolve it.