Wood stove inserts fill up the entire fireplace and usually extends out to the edge of the hearth. We have one in a fireplace with the chimney located in the center of the house. After a day of running the chimney mass heats up and keeps the house toasty warm.
Ok, thanks.
I don’t think our (gas) fireplaces are masonry :-(
We have LOTS of wood, on/around our property.