What Is the Ash Pit in a Fireplace For? | eHow.com
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An ash pit is a compartment at the base of the fireplace that holds fireplace ashes. This compartment, usually a cavity surrounded by cinder blocks or concrete, is reached through a small metal access door mounted flush in the fireplace floor or wall. Open the door and sweep ashes into the holding pit until they can later be removed. Does this Spark an idea?