Hello, I had my chimney rebuilt last fall and after doing some more research on the subject i've decided that they did a crappy job on the crown. It's built using brick mortar instead of concrete and doesn't overhang the bricks what so ever. Also, they poured it tight against the clay flu's. Here's my question. If i decide to go ahead and chip the old one off and pour a nice concrete one, what do I use for the bottom of the form? In other words, if I remove the crown i'll be looking at the lath that they used to support the mortar which obviously won't prevent concrete from pouring into my chimney.