What’s the Best Way to Prevent Ice Dams on a Commercial Building? 

If you’re managing a commercial building in the Midwest or Northeast, you probably dread the winter season—not just because of the snow and ice, but because of what they can do to your roof. Ice dams are one of the most frustrating (and expensive) problems building owners face in cold climates. 

At Weather Shield Roofing Systems, we’ve been helping commercial property managers, owners, and investors protect their buildings for over 40 years. And we get it—dealing with winter roof damage is stressful. You want real answers, not vague advice. So let’s break down exactly how to prevent ice dams from forming on your commercial roof in the first place.  

What exactly causes ice dams on commercial roofs?

Ice dams form when heat from inside your building escapes through the roof, melting the snow above. That melted water runs down the roof, hits the colder edges or overhangs, and refreezes. Over time, this process creates a dam of ice that blocks additional meltwater from draining. That water backs up under your roofing membrane or panels, leading to roof leaks, soaked insulation, and costly interior damage. 

Most people assume ice dams are just a pitched roof issue, but they can form on flat commercial roofs too—especially near roof edges, scuppers, and clogged internal drains. 

What’s the best way to prevent ice dams on a commercial building? 

The best way to prevent ice dams is to keep your roof temperature consistent. That means managing insulation, ventilation, drainage, and snow buildup. Here’s how to do it: 

How does insulation help stop ice dams? 

Inadequate or uneven insulation allows heat to escape from the interior into the roof deck. That’s what starts the melting process that creates ice dams. Adding or upgrading insulation helps retain interior heat where it belongs—in your building—not leaking into the roof system. 

Pro tip: If you’ve had a history of ice dams, have a professional conduct a thermal imaging scan to identify hot spots where heat is escaping.  

Do roof vents help prevent ice dams? 

Yes, but only when designed properly. Proper ventilation allows cold air to flow under the roof deck, helping keep roof temperatures even. This is especially important for pitched roofs. For flat roofs, it’s less about ventilation and more about ensuring your insulation and drainage systems are doing their jobs. 

How important is drainage in preventing ice dam damage?

Extremely important. Even if some melting occurs, you need clear, functional drainage to move water off the roof before it can refreeze. 

Clogged scuppers, downspouts, and internal drains trap water on the roof. When temperatures drop again, that water turns to ice—sometimes creating massive dams that weigh hundreds of pounds and cause structural stress or membrane damage. 

Preventative step: Schedule routine roof inspections before and during winter to check for clogged drains or ponding water. Weather Shield’s Max Life Roof Care™ program includes seasonal maintenance specifically to help with issues like this. 

Should I remove snow from my commercial roof?

Yes—but carefully. If heavy snow builds up, especially near edges or around rooftop units, the chance of ice dams forming goes way up. But removing snow improperly can damage your roofing system. 

Only use professional snow removal services that understand commercial roof systems. Avoid using metal tools that can puncture membranes or damage flashing. 

Rule of thumb: If snow exceeds 6 inches, or if your roof tends to have ice dam problems, have it cleared. Don’t wait until the next freeze. 

Can heat cables help stop ice dams?

In some cases, yes. Heat cables (also called heat tape) can be installed along roof edges or inside gutters to help melt snow and ice in critical areas. They’re most effective as a temporary or supplemental solution, not a substitute for proper insulation and drainage. 

They’re especially useful on complex roofs with lots of angles, valleys, or shaded areas where snow tends to sit. 

Note: Improperly installed heat cables can cause more harm than good. Always have a professional install and monitor them. 

What if I already have an ice dam—what should I do?

Don’t try to chip it away with a shovel or hammer. You could damage your roof and make leaks worse. Instead: 

• Use calcium chloride ice melt (never rock salt) in nylon stockings and lay them perpendicular to the roof edge to create channels for water to flow. 

• Call a professional roofing contractor to safely remove the ice and assess any potential damage. 

• Schedule a roof inspection to understand why it formed—and fix the root cause. 

How can Weather Shield Roofing Systems help?

At Weather Shield, we’ve seen firsthand how damaging ice dams can be—and how preventable they are with the right steps. That’s why we help our clients build custom winter prep plans that focus on: 

• Roof insulation and ventilation reviews 

• Drainage and scupper inspections 

• Snow removal protocols 

• Preventative maintenance through our Max Life Roof Care™ program 

With decades of experience in commercial roofing, our team helps you avoid emergency roof repairs by stopping the problem before it starts. 

What types of commercial roofs are more prone to ice dams?

Flat roofs with poor drainage are especially vulnerable, as are older pitched roofs with minimal insulation. Buildings with complex roof geometry, parapet walls, or rooftop HVAC units that melt snow unevenly are also at higher risk. 

If you’re not sure how vulnerable your roof is, we recommend scheduling a fall inspection—before winter weather hits.  

Can ice dams void my commercial roof warranty?

Sometimes, yes. Many manufacturer warranties don’t cover damage from “acts of negligence,” which could include failing to maintain your roof or not addressing insulation issues. 

That’s why it’s so important to take preventive measures before winter starts. It protects your investment and keeps your roof warranty intact. 

At Weather Shield Roofing Systems, we believe in helping commercial property managers make smart, cost-effective decisions. Preventing ice dams is one of the best ways to avoid emergency roof repairs, extend your roof’s lifespan, and protect your building all winter long. 

Need help preparing your roof for winter? Our team is here to help. Contact us today for a seasonal inspection or a custom winterization plan! 

Kyle Bruinsma

Account Executive

Since 2019, Kyle Bruinsma has delivered high-quality, cost-effective commercial roofing solutions at Weather Shield Roofing Systems. As both a roofing professional and commercial property investor, he brings a unique perspective to each project—treating every building like his own. Kyle values the strong team culture at Weather Shield, where everyone works together to keep customers dry.