Well if you'll allow me to digress from the GFCI issue, the code requires Ground Fault protection for Fixed Outdoor Electric Deicing and Snow Melting that is seen as a possible location for a GFCI receptacle. This should be a circuit that is protected by a breaker and can not be substituted by a a receptacle. In fact the breaker is the only device available for this type of installation. The GFPE has a trip level od 30-50 ma as I recall and the GFCI has a trip level of 4-6ma.
