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Roof Deicing Cable Installation and Use (Podcast)

In this episode, John Maher interviews Brett Rogenski, General Manager of Master Roofers, about roof deicing and cable installation. Brett explains how ice and snow buildup can cause dangerous ice dams and falling snow, leading to property damage and injuries. He details how deicing cables work with thermostats to melt ice safely and prevent dam formation. Brett emphasizes proper design considerations, including roof pitch and attic insulation, and advocates for professional installation to avoid DIY mishaps. This discussion provides homeowners with practical tips for safeguarding their roofs during harsh winter conditions.

John Maher: Hi, I am John Maher and I'm here today with Brett Rogenski, general manager of Master Roofers, the most trusted roofing company in New Hampshire for over 80 years. Today we're talking about roof deicing, cable installation and use. Welcome, Brett.

Brett Rogenski: Thanks, John. I appreciate you having me today.

What are Dangers of Ice and Snow Buildup?

Maher: Sure. So, Brett, what dangers to a home can be caused by ice and snow buildup on roofs?

Rogenski: Sure. The two things that jumped to my mind immediately, and part of it depends on the type of roof that it is, is number one, snow and ice sliding off the roof so causing a physical danger or damage. Damage to your shrubs in front, damage to a person underneath, damage to a vehicle. I personally went through a situation where I had snow slide off of a steep pitch roof land on the front of my brand new minivan and absolutely crushed the hood of it.

Maher: Yeah.

Rogenski: And the only good news is I'm like, well, better my minivan hood than a person, right?

Maher: Sure.

Rogenski: So yeah. So, one risk is snow load shedding and it injuring somewhere or causing property damage. So that's one item. The second concern is the buildup of ice dams on the soffits of your roof because ice dams, as they build up then cause damage. They can cause leaks within your home. They can cause damage to your roof. They can cause significant damage to your property. So deicing cables, heating cables, are capable of minimizing the risk of both of those items. And those are the two most common things that we're helping people with by installing heating cables.

What are Heating Cables?

Maher: So, a lot of homeowners might not really be familiar with heating cables or deicing cable systems. Tell us a little bit more about what they are and how they work.

Rogenski: Sure. So, to look at them, they look like a piece of, oh, it's a piece of wire. Kind looks like old cable TV cable.

Maher: Okay.

Rogenski: It's typically black, although it can come in colors. And what it is is a resistance wire. So there's a couple of wires in there inside of a UV protected sheath, because it's obviously outside. And that wire, there's a resist that's tied to a thermostat where we set a high temperature and a low temperature. So where does it kick on? Where does it kick off?

And it sends electrical current through the wires creating resistance, and the resistance creates heat. So when it's doing that, that goes on and it creates resistance in that wire. And we actually take that wire and we put it in the areas where there's potentially trouble. So, for instance on a standing seam metal roof, we may run it up and down certain parts of that standing seam metal roof which has those vertical channels.

On a more typical asphalt shingle roof, you'll see where we typically go, kind of a zigzag-ish pattern along that edge within those first three feet from the edge back, and that's where your soffit is and can cause ice damming. So we actually-

Does Heat Wire Go On The Whole Roof?

Maher: You wouldn't typically put it all over the entire roof, you'd just put it on those first couple of feet?

Rogenski: Exactly. Because those first two to three feet, that's where ice dams form because your roof has heat escaping up to it, your attic does, melting that snow which then comes to the edge, which is cool because it's a soffit and refreezes and causes the ice dam. So by now having this heated cable on the edge where essentially we're creating a channel that cable will not allow ice to form in that area.

And then that channel that it creates allows the water that's coming down to drain and go away and not create the ice dam. And the thermostat that I talked about is interesting as well. As I mentioned, we set a high temp and a low temp on it, so it's not running all the time. It only comes on when you need it temperature wise. It's obviously not going to snow when it's 45 degrees outside.

So, we set a high and low temperature, and then what it does is it actually modulates itself based on the actual outdoor temperature. Because if you think about it, put the same amount of electricity through that cable at 28 degrees as it would at -20 degrees. That heat would just dissipate. It wouldn't allow it to effectively melt ice and snow and those sorts of things.

So, what it does is it actually may put out whatever, 100 watts at 28 degrees, and it may go up as high as like 200 watts going through that cable at -10. So, it actually makes the cable hotter when it gets colder outside. Does use more energy doing that, but it's effective. And then it actually brings itself down as it gets closer to the freezing point and above. So takes care of itself.

Can Homeowners Shut Off The Deicing Cable?

Maher: Do you have any way to shut it off? Like say we just happen to have a winter where we're not getting a lot of snow so you just don't really need it. Is there a switch that you can just shut it off?

Rogenski: You can certainly do that. We have you work with an electrician to provide an outlet, and many people do exactly that. They have a switch tied to that outlet so they can put it off. Some people deal with it as a breaker in their breaker box and choose to shut that off.

But a lot of folks do a switch. But again, with that thermostat that's tied to it, remember if it's X temperature outside and it's outside the range, it's not going to come on. So, it's not just in there running all the time burning up your electricity. It's only going to come on essentially within the temperature range where it's decided to be needed. But yeah, you can absolutely shut it off and we have plenty of people who choose to do that.

Are Deicing Cables for All Types of Roof?

Maher: Are deicing cables suitable for any type of roof?

Rogenski: Yeah, they can actually used on any type of roof. They're certainly most common on asphalt shingles because asphalt shingles because of the granular surface of them, they don't actually tend to shed snow. Most of the time you see snow coming off a roof. If you see a big snow slide, it might be on a slate roof or on a metal roof or something like that.

Asphalt shingles, because of that granular surface to them, everything tends to want to grip. But that then creates that problem of building up ice and that sort of thing. So, I would say they're very common on asphalt shingle roofs. The other place that a lot of times that they're used is on standing seam metal roofs, and that's more about that whole snow slide thing. It might not be a place where they can have what we call snow rails that hold it back. So instead they choose to put in a deicing cable to simply melt that away.

What Does Master Roofers Consider When Designing a Deicing Cable System?

Maher: Okay. What are some of the factors that Master Roofers consider when designing or installing a deicing cable system to ensure optimal performance?

Rogenski: Sure. One of the first things is pitch of the roof. So how much is this going to be trying to shed? So pitch of the roof is one certain thing. Second thing is in the design process, and this surprises a lot of people, we're going to ask to see your attic. Your attic shows us the other side of your roof. We all see the shingle side and we think, oh, that's my roof. Well, there's another side, it's up in your attic.

And what we're really looking at there is insulation. So, we're seeing how well insulated you are and how well-ventilated that attic is, which then leads to heat buildup if it's poor, and we're doing that so that we can say, well, what's the melt rate going to be on this?

How much is going to be coming down here, a poorly insulated attic or poorly ventilated that maybe can't be remediated? We're going to have more linear feet of deicing cable put in than in a situation where it's a very well insulated, very well ventilated attic where we go, well, the melt rate's not going to be as high, so we can actually use fewer linear feet to make sure that that soffit area stays open.

When to Install Deicing Cables

Maher: Is it best to get a deicing cable system like this installed during the summer so that you're prepared for the winter months? Or is it possible for you to install them actually in the winter?

Rogenski: Sure. So, we can install them during any season. Is it easier probably for everyone to be done anytime except for when it's snowy and icy? Yeah, absolutely. The truth of the matter is, a lot of times folks don't know that they have this problem until there is snow and ice on the roof. So, we come and we help them remediate whatever the immediate situation is, and then at that point we can install those for them rather than wait until spring.

So, certainly the way we like to meet people who are interested in putting deicing cables up is we'd like to meet them before it's a problem so we can install the proper equipment so they never have a problem. The reality is a lot of times folks didn't know they had a problem until they have a problem. We help them address it, and then we were able to deploy this to make sure that we don't all have to live through this together again.

What Is Considered When Installing These Systems?

Maher: All right. And then for homeowners who are considering a deicing cable installation, should they schedule a consultation with Master Roofers to really talk about what the best system is and have you, like you said, check out the attic, check out the roof, and determine what the best setup would be?

Rogenski: Absolutely. Yeah. This is something we don't run on down to the big box store buy some cables and huck them up there and see what happens. There's an actual design. So, yeah, what we recommend for anyone who's having issues with ice damage or feels they need deicing cables, which also go in gutters frequently and that sort of thing, give us a call or reach out to us.

We've got great information on our website, masterroofers.com, and you can even schedule a consultation right there on the website. You can submit a form to request one. So give us a call, go to the website and schedule a consultation. We'll come out and we'll assess your situation because every design is different. So we'll assess the situation, review it with you, and design a solution that's just right for you in your home.

Maher: All right. Well, that's really great information, Brett. Thanks again for speaking with me today.

Rogenski: Thanks so much. I appreciate you having me.

Maher: And for more information, you can visit the website at masterroofers.com or call (603) 623-4973.