I was in GJ last week visiting the fam, and had a chance to help my dad take down a chimney on a house he's working on.
Take that, bricks
What is crazy is the construction method the original builders used. Here's a simple drawing of a section of the house:
Building code? What building code!
Apparently, they were either trying to save bricks, or idiots, because they just stacked the bricks right on the roof deck. They did this in two places, and the roof was visibly deflecting under the weight. After this, My dad wrapped the chimney in styrofoam and chicken wire and stucco'd the whole thing. Much less likely to come crashing through the roof and making a general mess of the living room.