The fireplace depicted in BIA TechNote 19 (above) is unnecessarily overbuilt. I've never seen a brick foundation like the one shown and the chimney wall only needs to be one brick wythe thick.
To promote a more economical masonry fireplace a good start would be to show a "code minimum" masonry fireplace such as the one in the NYCMA TecSpec#3 or the McGee "Real Thing" fireplace:
MeGee "Real Thing" Fireplace
Further improvements would be to keep the fireback straight and incorporate a better manufactured clay smoke chamber. I may have a bias, but I think it's hard to beat the Rumford with an extruded throat and a manufactured smoke chamber - not only potentially the cheapest masonry fireplace on the market but the best performing - known for 200 years to be efficient and tested recently to be cleaner than an EPA certified wood stove.
Buckley Rumford Fireplaces
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