Garage firewall

I inspected a home today that has a metal wood burning fireplace installed in the living room in the common wall of the living room and the garage. The garage side of the fireplace is bare sheetmetal not covered with type X sheetrock.
Is this considered an interuption of the garage firewall?
Can it be left as is, or should it be wrapped in fire rated rock?
Can anyone help?

Roy Drangstveit

Roy, if you mean the metal of the back of a zero clearance fireplace is exposed with open studs/framing, then, that would be a breach of the fire separation wall.

Otherwise, pictures would be helpful.