I'm having a gas insert installed into my masonry chimney next week. The installers are doing all the chimney work and running a new gas line to the fireplace, but they say that they're not going to do anything electrical. So I'll have a nice new fireplace with an ugly wire snaking across the hearth to the nearest wall outlet at the side of the mantel to power the built-in blower.

Since I've done a fair amount of wiring myself, I'm confident to run a line through the wall and into the fireplace cavity via a hole drilled through the cinderblock structure and brick surround of the fireplace. But I'm not certain about code requirements for this. What would be the best solution? Run a line to a new junction box inside the fireplace cavity and splice in the cut cable from the blower in there? Or put a standard outlet in the cavity and simply plug in the blower?