What Are Alternative Firewall Backings for Wood Stoves?


According to the National Fire Protection Association, the standard and minimum clearance for radiant wood stoves is 36 inches (NFPA). When the wood stove is positioned at a distance of 36 inches away, a broad range of materials may be employed for ornamental purposes. If the wood stove is situated any closer than 36 inches away from the combustible building materials, the materials must be able to prevent heat transmission into the flammable building materials in order to be safe and to comply with fire and building rules.

Material Characteristics

To prevent an ignitable surface from overheating is a desirable quality in the backing material for a firewall, whether it be a single material or a mix of materials. That implies the outside surface that faces the stove won’t be able to transfer heat to the building elements like wood framing or insulation. Either the materials must be able to reflect the heat back into the room or they must have a low capacity to conduct heat in order to prevent the heat from travelling through the material.

Two-Part Systems: Sheet Steel

A 28-gauge sheet metal with free-flowing air between the sheet metal, the floor, and the ceiling is one of the most effective methods to let installation closer than 36 inches. This is one of the most efficient ways to enable installation closer than 36 inches. The metal in question is a fantastic heat conductor. It performs the function of a heat sink by absorbing the heat that is generated by the substance. The transfer of heat via air is relatively inefficient. Therefore, the air behind the metal serves as a barrier that prevents the passage of heat. This design gives homeowners and builders greater leeway in terms of the kind of materials that may be utilised behind the metal shielding.

Firewall Materials

There is a broad range of appropriate masonry and rock materials to use as the backdrop for a firewall, including river rock, flagstone-brick, cinder blocks, and more. The rock or masonry material should always have a thickness of at least two inches whenever it is used. Adobe and masonry that is coated in adobe have been used for the construction of fireplaces for many years, and these fireplaces have never posed a safety risk. Always keep in mind the crucial difference between combustible surfaces and heat transfer properties whenever you are selecting materials for the backing of your firewall. It is essential that nothing within the immediate area of the stove has a combustible surface. This implies that you cannot use raw wood, river pebbles that have been lacquered, surfaces that have been painted, or anything else that may catch fire easily. The manner in which the stove is installed, the distances between the various components, and the method in which they are arranged are of the utmost significance. If they are more than three feet away, you have a great deal of creative freedom to use whatever ornamental material you desire; nevertheless, the surface of the material shouldn’t be combustible in any manner. When the distance between the two objects is less than 36 inches, the best alternative material is vented sheet metal because it can suck the heat in and then block it from transferring. Behind the metal heat screen, additional ornamental materials with non-combustible surfaces, such as glass block, ceramic tile, bespoke ceramics, or clay, may be employed.

Heat and Flammability

When choosing materials for your firewall backing, remember this important distinction between flammable surfaces and heat transfer characteristics. No materials in the vicinity of the stove should have a flammable surface. That means, no lacquered river rocks, painted surfaces or raw wood; one popped ember could ignite them. What is most important is the way in which you install the stove, the distances and how you configure the materials. Conceptually, if they’re 3 feet or more away, you have great latitude to use any decorative material you like, though it shouldn’t have a flammable surface. Closer than 36 inches, the primary alternative material is ventilated sheet metal to pull the heat in, then stop its transfer. More decorative materials with non-flammable surfaces may be used behind the metal heat shield: glass block, ceramic tile, custom ceramics or clay.