Soapstone fireplaces are extraordinarily efficient thermal mass heaters—the fire’s heat, captured in the mass of soapstone, is released slowly and evenly over time, long after the fire has gone out. One quick firing of wood for two to four hours produces up to 24 hours of radiant heat. Masonry heaters are substantially more efficient and much safer than iron stoves, and are not drying, since they transfer heat from one object to another rather than warm the air. “Air has little mass and so holds little heat,” explains Pihl. Blown hot air creates what you might call ‘indoor weather’ and stratifies in a room. Hot air gusts up from the register and moves to the ceiling, then to the walls, where it cools and falls to the floor. Moving air, even if it’s warm, actually cools you with the evaporation effect.”
While blown hot air costs less to install, radiant systems pay off by using less energy. They are a great complement to solar heating, as the rock, brick or water heat-storage system required for one can also serve the other.
Pihl presses his hand against a stunning fireplace / bakestove in his showroom. “Feel this,” he instructs. It’s smooth, already warm from sunlight, even when it hasn’t been fired. Every piece of soapstone has its own individual character and special beauty, formed over billions of years by nature, so even standard models are unique. Though his designs are cutting-edge and offer the latest technology, masonry heaters have been used in northern and central Europe for centuries. Pihl believes they were probably used thousands of years ago.
In The Book of Masonry Stoves, David Lyle describes clay ovens used 5,000 years ago in the Ukraine by people of the Tripolye culture. The “peasant” oven was used at least 4,000 years ago in Rumania, Poland, Yugoslavia, Latvia, Estonia, Finland and elsewhere, not only for cooking and heating, but for sleeping. “The architectural quality of some later ovens—massive affairs with one or more ovens for baking, stairs leading to a sleeping platform, cooking areas, spark hoods, candle niches, drying could be outstanding,” he writes, noting that some were beautifully decorated with tiles, while others had elaborate designs painted on them. When the mini-ice age began in the late 1500s, stoves once again became the center of the home.