How it works
Heat tape does not de-ice a roof. It melts one narrow drainage channel through whatever ice forms, so water running off the warm part of the roof can escape rather than pooling behind an ice dam and working its way under the shingles.
It is usually run in a zigzag along the first few feet of roof edge, then looped into the gutter and down the downspout — because a channel that stops at the gutter just refreezes there.
What it actually costs
Cable itself is the cheap part. The real costs are the dedicated exterior GFCI circuit most installs require, and the running cost: self-regulating cable typically draws 3–9 watts per foot. On a house with 120 feet of roof edge, running through a Kansas City cold snap adds a noticeable amount to a winter electric bill, every winter, for as long as you own the house.
Why we do not install it
Ice dams are a heat problem, not a gutter problem. They form when heat escaping the living space warms the roof deck, melts snow from underneath, and that meltwater refreezes when it reaches the cold overhang. Heat tape does nothing about the escaping heat — it just gives the resulting water an escape route.
In almost every Kansas City house we have looked at, the durable fix is attic insulation and air sealing, plus balanced soffit and ridge ventilation so the roof deck stays the same temperature as the outside air. That is roofing and insulation work, not gutter work, and we will tell you so rather than sell you a cable.
What we do instead
Where gutters are genuinely contributing, the honest fixes are ones we can stand behind: correct gutter sizing and pitch so water is not sitting in the trough to begin with, enough downspout capacity that the system drains before a freeze, and micro-mesh guards that keep the trough clear of the debris that traps standing water. If your issue is ice at the overhang, we would rather point you to a good insulation contractor than sell you something that plugs in.