Without fireplace doors, the fire draws heated air from your living space out the chimney. The heating effect of a fireplace is largely due to radiated heating, by which objects around the fireplace are heated up, and some of this heat is transferred into the air. Although heat radiates from the hearth, the fire draws colder air into your living space. Research has found that energy-efficient fireplace doors reduce air flow from a heated room, keeping the room warmer.
Homeowners with vented gas logs can also benefit from a glass door addition. Using glass fireplace doors on wood-burning or vented-gas fireplaces will make the room feel warmer than normal. Some fireplace units may also incorporate a blower to transfer the heat to the air via convection, resulting in a more comfortable heated space and a lower heating load.
Choosing the right fireplace door
Before you start shopping for glass fireplace doors, you need to know what type of fireplace you have. There are two types of fireplaces:
- Masonry fireplaces are made of brick and mortar.
- Zero-clearance fireplaces (also called factory built fireplaces) are made of metal and prefabricated in a factory, although the hearth may be lined with firebricks. The chimney is a metal pipe, possibly topped with a round metal chimney cap.
Learn more on fireplace energy savings tips from the U.S. Department of Energy website