Heating cables for roof?

[Steven Greenwell]

We have had problems the last couple winters with ice in our gutters. I'm wondering if it would be helpful to have heating cables installed on the roof before next winter. Has anyone had this done? What's your experience? Does it make a difference and what should we consider to budget for the project?

Any feedback would be appreciated.

[Will Brown]

I think ice on the edges of the roof and the gutters is caused by melting snow, most often due to heat escaping through the roof. So I think it is likely that heating cables would just melt more snow, which would produce more water going into the gutters to freeze, compounding your problem.

I think when many of our homes were built, the attic was unfinished, and certainly unheated. so the air inside the attic was as cold as that outside, which kept the snow from melting. Many of our attics were then finished, often with insulation put right on the inside of the roofboards. Insulation is nice, but when you take away air circulation space right under the roof, you no longer have any cold air to match the outside air, and melting snow becomes a problem. I think when they finish and insulate an attic now, they put plastic gutters along the inside of the roof, which allow air to circulate through the openings at the eaves up to the vent at the ridge. But I think that is a relatively new way of approaching the problem, and many of us are stuck with poor circulation (if you crawl into your eaves, you should find holes in the fascia that allow air circulation; many people have blocked those holes, intuitively it seems to be the right thing to do, but actually can cause an ice problem.

I'm not a roofer, but I've read a lot about this, since my attic is finished and insulated. I didn't find an economical solution. I think that when my current roof wears out, I am going to have them remove it, and the roofboards underneath, install the gutters, and then put down new roof boards and a roof. I'm not looking forward to having to pay for that.

I think heating cables on the gutters would help in melting the ice and letting the water drain, but I think you'd have to put them around the gutters and the drainpipes to insure a clear flow.

[Stan Austin]

Steve---- Will's analysis of the problem is essentially correct. Not only should an attic be properly ventilated, which means the plastic liners along the rafters but also soffit vents and peak or ridge vents. This ventilation is good for the winter and the summer.
A roofer is the person who can accomplish most of these tasks.
Get the ventilation right first and then if it's still needed consider the heating cables.
Stan

[Charlie Page]

I'm thinking about heating cables for our gutter in the front, facing west. When the sun shines and it gets close to 30 the roof heats up. The snow starts to melt and run down. Then it freezes in our gutters which end up overflowing. We end up with 5 foot ice cicles and ice on our driveway. I'd like to keep the gutters ice free and maybe heating cables are the way to go?

[Will Brown]

I've sometimes wondered if that would be a good use of solar energy (since we're all interested in going greener). Since the melting occurs when the sun is up, a solar panel could extract dc current at the same time, providing the heat, with no need for an expensive and complicated storage system to provide heat during the night. I'm no engineer, so I don't know how large of a panel would be needed, but it sure seems like a good use of the technology.

I've often wondered why our government builds bridges, which freeze easily, which breaks up the pavement and which requires salting, doesn't put up some solar collectors and a battery field with each bridge, and eliminate the freezing and corrosion problems; I guess they like having bridges last only a few years.

In fact, if Obama is serious about lowering our carbon footprint, he could give me a couple of billion dollars and I would conduct a solar heating experiment on my driveway and sidewalk, and throw away my snow shovels. This could be made part of the health care program, too, as it would lessen my chances of having a heart attack.