The fireplace must have a listed firestop in fireblocking at each ceiling level. The insulation must be sheathed over just like any other exterior wall and yes, that Kraft paper must be sheathed over or otherwise protected from ignition sources such as the fireplace. The stated clearances must be met around the fireplace. The blown down insulation must be removed. The elbow and horizontal run must be supported per mfrs. instructions.

This appears to be a little Bvent factory built fireplace--not an insert. Inserts are 'inserted' into exisiting fireplaces. From the physical size and 4" B-vent, I would guess it is rated for less than ~ 22,000 BTU/ hr. input. The fact there is so much wasted room is not a problem per se. In fact, it allows a retailer to yank that unit and install a large one at a later date.

Why in the world did they exit the chase and enter the attic with the vent? Nice job of hacking huge holes in that gable wall, though I don't understand why it is insulated up in the attic.

This installation does not comply with the Fp mfr., B-vent mfr, or building codes.

hth,
Bob

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