The tile appears to be laid on a cement slab, which is supported by 4-by-4-inch posts resting on a couple of concrete piers. I'm not quite sure how to get the hearth back to level with the ...

The thickness of the cap slab would be 21/2 inches at the outer edge and would get thicker as it approaches the clay flue liners. It would have a generous slope, ensuring that water flows to the ...