Question: We have a zero-clearance pre-fab fireplace that a sweep said could take 26" to the top of the rear flue on a stove setup on the hearth. Answer: There are some factors which could make it dangerous to install a freestanding radiant stove on the hearth of a pre-fab fireplace. Be sure to ask your dealer and sweep about it and get a second opinion. To my knowledge it does not meet most codes and specs since there is wood in the wall directly behind the facing of the fireplace and the pipe and/or stove might be too close to this. The chimney would also need to be fully lined to the top, even if other things were OK.