Fireplace and Fireplace Insert Definitions
Some fireplace inserts are marketed as fireplaces. If brick or stone material is visible within the firebox, as in the Masonry Fireplace, the Low Mass Fireplace, or the Masonry Heater, the fireplace is not required to be removed or replaced.
*Earthcore Industries, LLC Standard Series 36C
Masonry fireplaces are typically built of brick or stone and are constructed on site by a mason.
Masonry fireplaces are not used as a primary source of heat; their function is primarily for ambiance. Fireplaces are typically very inefficient heaters.
Low Mass Fireplace
*International Stove Builder - FP-1 LM
“Low mass” fireplaces are engineered and pre-fabricated in a manufacturing facility prior to installation.
Low mass fireplaces, are not used as a primary source of heat; their function is primarily for ambiance. Fireplaces are typically very inefficient heaters.
*RSF Focus 320
Fireplace inserts are similar in function and performance to free-standing wood stoves, but are designed to be installed within the firebox of an existing masonry or metal fireplace. A fireplace insert could be required to be removed or replaced.
The example above is an RSF Focus 320 and is marketed as a "fireplace," however, it is required to be EPA certified.
A masonry heater is a site-built or site-assembled solid-fueled heating device, consisting of a firebox, a large masonry mass, and a maze of heat exchange channels. It stores heat from rapidly-burning fires within its masonry structure, and slowly releases the heat into the home throughout the day. Masonry heaters are typically very efficient heaters, and currently do not require EPA certification.
Wood Stove and Wood Stove Insert definitions
*Blaze King Industries, Blaze King
A wood stove is an appliance that is usually made of cast iron, steel, or stone. Wood stoves that burn wood for fuel can be used as a primary or secondary source of heat.
Wood Stove Insert
*Blaze King Industries, Blaze King Princess
Wood stove inserts typically have metal fireboxes, and could be required to be removed or replaced.
Note: Definitions above were taken directly from the EPA Burn Wise Website