All About Firebox Refractory Panels

All manufactured wood burning fireplaces (Prefab fireplaces) are designed and built with what are called refractory panels, which line the inside of the fire box.

There are four individual panels.  The hearth (floor), rear wall, and two side walls.

The manufactures use these heat resistant panels for a few reasons.
One, they are the first line of defense in the heat insulation properties of a prefab fireplace.  Often prefab fireplaces are referred to as "zero clearance" fireplaces.  Although nothing is actual "zero clearance", the clearances to combustible materials such as wood framing is within 2"-4" of the unit. So with these tight clearances, it is necessary to have layers of protection with air gaps in between to properly dissipate the heat.

The next reason for use of these panels is, when they heat up, they provide some extra radiant heat.

The last reason is for looks. The refractory panels are often molded with a brick pattern to simulate a firebrick fire box.

Normal fireplace operation of extreme heat to cool and contact with pokers and slamming wood will cause the panels to crack and deteriorate. Usually the rear wall and floor will go first. It is necessary to replace these panels with new, to keep the same fire rating as was UL listed for that unit.  Additionally, new panels can be cut and fit if needed, from after market refractory panel slabs.

Also, our friends at Chimnee Cricket offered a free, how-to, do-it-yourself tutorial on how to replace a refractory panel for your fireplace.

Until next time...

Nick