On Sep 13, 12:32*pm, "Sheldon" wrote:
Why are so many chimneys built with the flue(so) that extend above the
crown?

For Looks?

To improve the chimney draw? *I would think the small increase in height
would make little or no difference

Makes a world of difference

To allow the chimney to meet code
*I would think the chimney could just
have been built at the correct height in the first place.

Sheldon