fireplace firebox close up photo


Originally contributed by Jeff Butler • last updated 12/17/2020

When most people think of a fireplace, they often picture sitting in front of a big stone hearth, with the flames of a warm roaring fire crackling away inside a...firebox? A firebox can play an important role in most types of fireplaces, but what is it exactly?


The term firebox most commonly refers to the part of a fireplace (or stove) where the fuel is combusted. In other words, it’s the space inside the fireplace where the flames are located. In traditional masonry fireplaces, the firebox is typically constructed from special heat resistant brick and is part of the foundation along with the ashpit and chimney. As part of a prefabricated fireplace insert, the firebox is usually made from metal and can be lined with decorative stone or glass. A firebox in a gas fireplace is usually part of the whole unit and typically contains a decorative (sometimes functional) fuel source, such as gas logs or glass beads, and the burners.

A Couple Of Things About Fireboxes

Whether you’re dealing with a traditional masonry firebox or you’ve got a new prefabricated fireplace insert, there are a few things you should keep in mind:

  • Despite being made from strong masonry materials, traditional fireboxes are not indestructible. Extremely hot temperatures and improper usage and maintenance could lead to structural problems or worse.
  • Most prefabricated fireboxes are meant for decorative purposes and could cause fires and other damage if used improperly. It’s important to follow the directions for intended use.