How high does mendota fireplace need to be framed

[anonymous1977]

Folks - I think I am being taken for a ride. I am thinking of doing a fireplace for a high ceiling and the mendota sales guys are saying I have to frame floor to ceiling because the pipe vents our vertically and goes out horizontally. So if they framed our 8 feet or so, it will look odd. If I add a hearth of 12 inches and the 57.5 inches in the attached picture to center of vent and add another 3 inches, I am still at 72.5 inches or 6 feet. So wouldn't I be ok only framing to 6 feet instead of the full wall?

 

[DAKSY]

As long as you meet the 3" requirement above the horizontal run of venting,
you can terminate your enclosure WITHOUT going all the way to the ceiling.
Not sure how good it'll look, stopping short of the ceiling. Then there's the
dust that's gonna settle up there...

 

[anonymous1977]

If my calculation above is right it comes to 6 feet which I don't think would look bad. Am I making an error? Why are they saying it needs to be 8 feet?