Winter in Calgary brings stunning snow-covered roofs and picturesque icicles hanging from eaves. But those icicles could be a warning sign of a much bigger problem—ice dams.
Ice dams form when melted snow refreezes at the edges of your roof, creating a thick barrier of ice that blocks proper drainage. Over time, trapped water can seep under shingles, leading to roof leaks, mold growth, and costly structural damage. The University of Minnesota Extension provides a detailed explanation of how ice dams form and what homeowners can do to prevent them.
Many homeowners attempt DIY ice dam removal, but this can be dangerous and often causes more harm than good. In this guide, we’ll cover:
- What causes ice dams (and why they’re common in Calgary)
- The dangers of ignoring them
- DIY methods (what works and what doesn’t)
- Why professional removal is often the best option
If you’re dealing with ice dams or want to prevent them before winter gets worse, explore our winter roofing services to learn how we help Calgary homeowners protect their roofs from extreme weather.
If you’re dealing with ice dams or want to prevent them before winter gets worse, read on—this guide will help protect your home and save you money.
What Causes Ice Dams?
While Chinooks offer a welcome break from the cold, they also accelerate snowmelt on rooftops, creating the perfect conditions for ice dams, water infiltration, and structural damage. As temperatures drop overnight, the melted snow refreezes along roof edges, forming thick ice dams that trap water and add excess weight to the roof.
This repeated freeze-thaw cycle doesn’t just lead to ice dams—it also weakens your entire roofing system over time. The constant expansion and contraction of asphalt shingles can cause cracking, curling, and premature wear, shortening the lifespan of your roof.
Homeowners often notice icicles hanging from their eaves before they realize they have an ice dam problem. While icicles may seem harmless, they often signal trapped water behind them, meaning hidden roof damage is already happening. Left unchecked, this buildup can put stress on your roof and lead to serious issues over time—issues that many homeowners don’t notice until it’s too late.
How Ice Dams Damage Your Roof and Home
Ignoring ice dams may not seem like a big deal at first, but the longer they remain, the more damage they cause. From minor leaks to major structural issues, ice dams can threaten the integrity of your home. Here’s what can happen if they’re left untreated.
Common Ice Dam Damage
- Roof Leaks and Water Damage – Melted snow backs up under shingles, leading to interior leaks, ceiling stains, and wood rot.
- Mold Growth and Insulation Issues – Moisture buildup in attic insulation reduces efficiency and creates the perfect conditions for mold, leading to potential health risks.
- Shingle and Structural Roof Damage – The freeze-thaw cycle weakens roofing materials, causing shingles to crack, curl, or loosen.
- Gutter and Soffit Damage – Heavy ice can clog, warp, or tear gutters away from the roof, leading to further drainage problems. Water seeping into soffits can cause hidden structural damage.
- Falling Ice and Safety Hazards – Icicles and ice chunks breaking off pose serious risks to people, pets, and vehicles below.
Severe Damage if Ice Dams Are Left Untreated
- Rotted Roof Decking – Water trapped under shingles can seep into the wood decking beneath, weakening the roof structure. In extreme cases, sections of the roof may sag or require full replacement.
- Wall and Drywall Damage – Prolonged leaks can cause water to travel down walls, leading to stained, warped, or crumbling drywall, requiring costly interior repairs.
- Foundation Damage from Water Seepage – Excess water pooling around the foundation increases the risk of cracks, shifting, or basement flooding—especially in older homes with poor drainage.
- Severely Compromised Attic Structure – Long-term moisture exposure can rot rafters, weaken trusses, and cause noticeable roof sagging, leading to major structural repairs.
- Complete Roof Collapse (Extreme Case) – If too much ice and snow accumulate, the excess weight can lead to partial or complete structural failure.
The longer ice dams remain, the greater the damage. Even minor ice dams can cause expensive problems over time. If your roof has already suffered damage from ice dams, schedule a roof repair to prevent further issues before they worsen.
Should You Try to Remove an Ice Dam Yourself?
If you’re dealing with an ice dam right now, you might be wondering if you should remove it yourself or just wait until spring. Some people swear by DIY methods like using a sock filled with calcium chloride, while others say it’s best to leave it alone. Even some professionals use chiseling, but they know exactly when to stop to avoid roof damage.
At the end of the day, removing an ice dam without addressing the cause means it will come back. It’s also easy to make the situation worse—damaging your roof, causing leaks, or even putting yourself at risk.
DIY Methods That Can Work (With Caution)
- Roof Raking – Removing fresh snow with a roof rake can help prevent ice dams from forming. Just be careful not to damage shingles.
- Calcium Chloride in Pantyhose – This can melt small drainage channels in an ice dam, but it won’t eliminate the dam entirely.
- Waiting Until Spring – Some homeowners prefer to wait, as the ice will eventually melt. However, this can lead to water damage inside the home if the ice dam is already causing leaks.
What Can Make Things Worse
- Chipping or Chiseling the Ice – Even though some professionals use this method, they know how to do it safely. DIY chipping can crack shingles and cause expensive damage.
- Using Rock Salt or Chemical Deicers – These products can corrode roofing materials and kill surrounding plants.
- Climbing Onto an Icy Roof – Even professionals use safety equipment. Without it, you risk serious injury.
If you’re set on trying to remove an ice dam yourself, be extremely careful. The real fix isn’t just getting rid of the ice—it’s addressing why it formed in the first place. That’s why having your roof inspected by a professional is crucial to preventing future ice dams.
Fixing the Root Causes of Ice Dams
Removing an ice dam is only a temporary fix. If you don’t address why it formed in the first place, it’s going to come back—sometimes worse than before. That’s why the real solution is figuring out what’s causing it and making changes to prevent it long-term.
Every home is different, and in some cases, ice dams are almost unavoidable. Some roof designs trap snow and ice no matter what, and even we have to return to install heat cables as a final solution. But for most homes, the problem comes down to three main factors:
1. Poor Attic Ventilation
Proper ventilation keeps your attic temperature stable, preventing uneven roof temperatures that lead to ice dams. If warm air is getting trapped, it heats the roof in spots and melts snow that refreezes at the eaves. Upgrading your attic ventilation can help reduce heat buildup and minimize the risk of recurring ice dams.
- Make sure soffit, ridge, and gable vents are working properly.
- Check that insulation isn’t blocking airflow.
- Consider installing additional vents if airflow is limited.
2. Insulation Problems
Attic insulation plays a big role in controlling heat loss. If too much heat escapes from your home into the attic, it speeds up snowmelt and ice dam formation.
- Upgrade insulation to prevent heat from escaping.
- Seal gaps and air leaks, especially around attic hatches and chimneys.
- Ensure proper vapor barriers to reduce moisture buildup.
3. Poor Roof Design or Drainage Issues
Some roofs are just prone to ice dams due to their slope, valleys, or drainage layout. If water can’t escape properly, it will refreeze and build up. Regular gutter maintenance is one of the simplest ways to improve drainage and reduce ice dam formation.
- Ensure gutters are clean and draining properly.
- Consider adding wider or heated gutters in problem areas.
- If your roof traps snow in valleys or low spots, additional drainage solutions may be needed.
4. When Heat Cables Are the Best Option
In some homes, ice dams are going to form no matter what. If your roof design or location makes ice buildup unavoidable, installing heat cables may be the best long-term solution. These cables create a controlled melt path, allowing water to escape instead of refreezing.
- Ideal for homes with chronic ice damming issues.
- Best for problem roof designs where ventilation and insulation alone aren’t enough.
- Professionally installed to ensure even heat distribution and effectiveness.
The key to stopping ice dams isn’t just removing them—it’s understanding why they form and making the right changes. In some cases, getting a professional roof inspection is the best way to find the underlying issue. If you’re unsure about your roof’s condition, our team can assess your ventilation, insulation, and drainage to recommend a long-term solution.
Get Expert Ice Dam Removal and Prevention in Calgary
If you’re dealing with ice dams in Calgary or the surrounding area, Whalley’s Four Seasons Roofing can help. Whether you need immediate ice dam removal, roof repairs, or a long-term solution like attic insulation upgrades, ventilation fixes, or heat cable installation, our team has the expertise to protect your home.
We believe in only doing the work that’s truly needed—we’ll never sell you something we wouldn’t recommend to our family. If you’re unsure about your situation, just give us a call for an inspection. Usually, they’re free (unless required for insurance claims, professional reports, or detailed photo documentation). We’ll give you the truth about your roof’s condition. Occasionally, there’s nothing that needs to be done, and in that case, you’ll walk away with peace of mind knowing your home is in good shape.
