Icicles might make your home look like a picture-perfect holiday card, but unfortunately, they can have severe implications on the well-being of your roofing system.
Before this year’s first snowfall, discover the most common reasons why icicles and ice dams form, so you can prevent them from wreaking havoc on your Indiana home this winter.
What Are Icicles and Ice Dams?
An ice dam is a build-up of ice on the edge of your roof. It prevents melting snow from draining off your roof and creates a backup of standing water. This water can cause damage to your roof, walls, ceiling, and other areas in your home.
An icicle is a piece of ice that hangs along the edge of your roofline. Although icicles are usually a sign of an ice dam on your roof, they are not the cause of ice dams. In fact, you may have an ice dam on your roof before you ever see an icicle.
Why Do Icicles and Ice Dams Form?
Ice dams require three elements to form—snow, heat loss, and freezing weather.
First, a storm dumps snow on your roof. Usually, when your roof is at a consistent temperature, the snow eventually slides off. However, ice dams occur when your roof varies in temperature, specifically when the top of your roof is above freezing temperatures while the lower portions are below freezing temperatures.
In this situation, the snow on the upper portion of your roof melts, but the water refreezes when it reaches the lower part of your roof. When this happens continually, it forms an ice dam. The ice dam prevents the remaining snow and water from draining, and since the upper roof is above freezing temperatures, the snow remains melted, which results in standing water trapped on your roof.
What Causes Heat Loss on Your Roof?
If your home has poor attic insulation, it may be transferring heat to your roof through a combination of conduction, convection, and radiation—the most common cause of ice dams.
Essentially, warm air moves through your ceiling and insulation through conduction—the process of heat traveling through a solid. Then, the heated air above the insulation rises, carrying heat to your roof through the convection process. The higher temperatures above your insulation increase the temperature of your sheathing with electromagnetic waves during the radiation process. The radiation makes your roof warmer than outdoor temperatures.
Heat loss can also be caused by air leaks, poorly positioned exhaust systems, and heat expelled from the chimney.
Just like ice dams, icicles require snow, heat loss, and freezing weather to accumulate. However, unlike ice dams, they form on the roof’s edge rather than the bottom portion of your roof, so they are more visible.
4 Ways Ice Dams Can Damage Your Roof
1. Gutter Damage
When ice dams and icicles form on your home, they cause your gutters to fill with ice and bend, break, or fall off your home. When your gutters become damaged, they may also cause damage to your fascia, downspouts, and other elements of your roofing system.
2. Roof Leaks
When standing water remains on your roof for weeks at a time, it will find its way beneath your shingles and flashing. Eventually, the water will penetrate through your roof decking, causing leaks in your attic.
3. Damp Insulation
Roof leaks can cause plenty of damage—including wet insulation. When your insulation becomes damp, it loses its ability to insulate your home correctly. This creates a vicious cycle—the moist insulation results in extra heat loss, the heat loss results in more ice dams, and the ice dams cause more roof leaks and water damage.
4. Structural Issues
When water becomes trapped between your waterproof protective barrier and wood-based roof decking, it can result in mold and mildew growth, rot, and severe structural issues. These problems compromise your roofing system and put your home and family’s safety at risk.
Tips to Prevent Ice Dams on Your Roof
It’s much easier to prevent ice dams than remove them. Take these action steps now to avoid the formation of ice dams on your home this winter:
- Remove snow immediately after snowstorms. You can use a push broom for flat and low-slope roofs or a roof rake for sloped roofs.
- Add extra insulation to upstairs ceilings to keep warm air inside your home and out of your attic. As a general rule of thumb, use insulations with a high R-value. This value measures a material’s resistance to heat flow.
- Verify your attic ventilation is removing heat from your home. If it’s not, install adequate ventilation to keep your roof deck cooler and prevent water from melting and refreezing.
- Install a waterproof underlayment between your flashings and decking. Waterproofing does not prevent ice dams, but it will prevent water damage to your roof if ice dams develop.
How to Fix Ice Dams if They’ve Already Formed
If your home already has an ice dam, don’t panic. Here’s what you should (and shouldn’t) do to remove the ice dam.
Do: Keep your attic well ventilated and insulated and remove air leaks to eliminate the melting and refreezing process. Eventually, your roof’s temperature will equalize, causing the ice dam to disappear. If your gutters aren’t backed up, you can also run hot water over the ice dam until the ice melts and runs through your drains.
Do not: Use hammers, shovels, ice picks, snow blowers, or chainsaws to remove ice dams. These abrasive tools may damage your roof even more than the ice dam will.
Get Your Roofing Questions Answered Before Winter Arrives
However, before your replacement, you might be wondering:
- Is the roof replacement process disruptive?
- How much should I budget for my project?
- Which roofing materials should I choose for ultimate weatherproofing?
Don’t worry—we’re got you covered. Get these questions (and more!) answered with our complete roofing guide!