Art 426, Exposed deicing and snow-melting equipment there is nothing on how or if the gutters/downspouts on a residential house should be grounded. The cable is listed and the manufacturer says to see instructions, which we couldn't find any mention of how to ground the gutters. Going to call manufacture tomorrow, but wondered if any northern electricians had so insight on this. Thanks again.

There should be no need to ground the gutters and downspouts because 426-27 requires the heating cable to have an conductive grounded sheath and 426-28 requires ground fault protection of equipment for the heat cable. These provisions should eliminate any need to ground the gutters and downspouts.
Don(resqcapt19)