Wow, 20 degrees - that is pretty cold for that far south. Fortunately I have a room in the basement so the temperature is easily workable year round.

Yes, the chimneys on fireplaces of the floors below all match up to ones above and each will eventually poke out the roof. That explains the somewhat awkward placement of the shared fireplace and the hot coal fireplace above it which both needed to match up with the fireplace on the 1st level.