Masonry heaters masonry-heater-mha.jpgare green on at least two counts, Smith explained, because they’re efficient and have cleaner emissions. “It’s very green. Because of the uncontrolled (fast) combustion in the fireplace you’re burning up all those gases.”

Emissions from masonry heaters are in the same range as for pellet stoves, though they were last tested in 1992. The masonry group hopes that new tighter EPA rules emissions on particulates will prompt new testing that could increase awareness of this type of heating. (To find out more about this issue, start with this EPA FAQ on particulate matter rated 2.5 to 10 micrometers in diameter, which comes from dust, dirt, soot and smoke).

Already some states have experienced fireplace burn bans, as local communities try to keep within federal standards.

“We embrace the EPA looking at the whole emissions issues because our testing has shown we’ll come out with a shining star….We have very little if any emissions going into the air,” Smith said.

Comparing the masonry heater to fireplaces is easy: Masonry heaters are far more efficient, though they do not produce the large blazing hunting party-type fire that some homeowners may desire aesthetically. But comparing the masonry heaters and pellet stoves is trickier. There are many differences – the pellet stove burns continuously, but uses recycled material; the masonry heater fireplace burns quickly, radiates heat for many hours afterward, but uses regular cut wood, a renewable fuel source, but potentially problematic depending on how it’s sourced.

Masonry heaters are custom or semi-custom projects and are more expensive, but they can heat larger areas, even the entire house; whereas a pellet stove heats a room or two, so it serves more as an ancillary heating system.