How To Backfill a Cast Iron Fireplace
Backfilling is the process of filling the (empty) room behind the fireplace with cement and vermiculite. The purpose of backfilling is to prevent the heat generated from the fireplace from heating the back room (which is of no value to the owner), on the contrary, we can push most of the heat forward. Backfilling is an important step for cast iron fireplace fittings. Incorrect backfilling can damage the cast iron back. Be very careful when trying to backfill a cast iron fireplace : the filling should be strong enough not to break, but not too strong to avoid damaging the back of the cast iron. Generally, an insulating mixture composed of 6 parts of vermiculite and 1 part of cement is mixed. Alternatively, you can mix 4 parts broken bricks, 2 parts sand, and 1 part lime. Put the corrugated paper, cardboard, or strawboard around the lower back half of the fireback before you try to backfill. In this way, when you light the fireplace, the cardboard or paper will burn off quickly, lea...