6 Reasons Roof Heat Cables are Ineffective for Ice Dams


Roof Heat Cables

If you have ever dealt with busted-up shingles and roof leaks due to an unchecked ice dam, you have probably considered a roof heat cable as your solution. However, roof heat cables are largely ineffective for ice dams.

In the following post, Roofer’s Guild defines roof heat cables and outlines six reasons why you should avoid using them to address ice dams.



What are Roof Heat Cables?

Roof heat cables, for those who haven’t ever had to think about them, are pretty much exactly what they sound like: lengths of cable, tape, or wire that are installed on top of your shingles that heat up to prevent water from freezing on your roof.


Why You Shouldn’t Use a Roof Heat Cable for Ice Dams

Roof heat cables sound like an innovative and clever way of preventing ice dams from forming on your roof. But before you haul off and pay someone to install them for you, take a minute to peruse our list of reasons why roof heater cables are actually not a great idea. 


1) Roof Heat Cables Can Be Dangerous

Think about it; you are putting heated pieces of wire on top of your roof. According to a Washington Post Safety notice citing a Consumer Product Safety Commission report, roof heat cables are responsible for around 2,000 structure fires yearly and over 100 injuries.

So, are roof heat cables dangerous? They absolutely can be. But roofing safety isn’t the only concern related to this de-icing method.


2) Heat Cables are not a Cure-All

Many people who start to shop around for roof heat cables have the same misconception: they think they will clear off all the ice from the roof. That isn’t how heating cables work.

Roof heater cables only melt snow and ice directly around them. When they work, you will usually see thin streaks that are the clear paths that cables melt in the snow and ice.

Their function is simply to clear enough space and melt enough ice to prevent ice dams and provide a channel for the water to flow to the gutters.

That being said, heating cables will not protect your roof if your gutters are clogged, and they will certainly not clear all the snow and ice from your roof.


3) Cables are an Added Utility Expense

If you have an average-sized roof, you will be looking at an average cost of $7.25 per day to run your roof heat cables. In the winter months, when you will most likely need to run your heater cables all day for days at a time, that adds up to a lot of extra money.

Now, the argument can be made that $7.25 per day may still add up to less money than repairing a collapsed roof, which is true.

But in most cases, homeowners don’t actually need to install roofing heater cables. Some regular maintenance and due diligence are enough for most homes to avoid dangerous ice dams in the winter.

For instance, raking your roof (safely) when snow accumulates on it is an effective and cheap way to protect it against ice dams.


4) Roof Heat Cables Require Precise Installation

If the contractor you hire to install your heater cables doesn’t have a lot of experience and investment in the project, your cables can very well become more of a problem than if they were never installed at all.

For example, the ice they melt can simply refreeze again on other portions of your roof if not installed cleverly and strategically. They need to be placed to channel all melted ice to the ground or gutters.


5) Cables Look Bad in Summer and Spring

Unless you live in the Arctic Circle, you aren’t going to need your roof heat cables year-round. While the snow covers most of the cables in the winter, in the summer and spring months, the cables are on full display to the neighborhood. I think broken Christmas lights are strewn atop your roof all year long.

Also, uninstalling the roof heat cable isn’t exactly DIY work. In short, it isn’t worth taking your roof heating wires down every year and then reinstalling them again every winter – especially when the average cost for roof heat cable installation is $447-$1200.


6) There are Better Ways to Address Ice Dams

Perhaps the most important reason why roof heat cables are ineffective for preventing ice dams is that there are much better ways to prevent them.

In most cases, ice dams are caused by heat escaping from inside, melting snow on top of the roof, and the melted snow running down to a colder area of the roof and refreezing.

Fixing these heat leaks is the most effective and beneficial way to prevent ice dams – and lower your heating costs to boot.


Final Thoughts

Risking a structural fire in an attempt to prevent ice dams with roof heat cables is unwise. First, it can be very dangerous and is not something you can do as a DIY project.

Secondly, the heat cable method doesn’t actually work that well in regard to ice dam prevention.

There are superior ways to address ice dams on your roof, and a professional roofer can safely execute them for an affordable cost.