Masonry heaters have been heating homes for centuries. First developed by Scandinavian and Russian masons, these ingenious wood-burning heaters provide long-lasting, continuous warmth with minimal emissions and maintenance. If you’re looking for a cozier fireplace option for your Katahdin Cedar Log Home, you may want to look into masonry heaters. They can be custom built by an expert mason experienced with the construction or excellent prefabricated designs can be purchased from companies like Tulikivi.

How Do Masonry Heaters Work?
Many woodstoves and fireplaces create only partial burning and smoldering that results in higher amounts of particulates and combustion gases being emitted. Most of the heat generated goes up the chimney with the emissions—in Finland, this is called “warming the crows.” Modern masonry heaters use directed air entry high in the firebox and convoluted channels that circulate air inside. These channels recycle gases and particles so that they are almost completely burned off. The channels also warm the soapstone or masonry veneer and other materials in the heater to give off a continuous, radiant heat. These heaters use natural draft to manage the burn and require chimneys 16- to 18-feet from the floor to their termination to maintain good draft.

Central Location for Optimal Heating
Masonry heaters are best suited for central locations in homes to provide radiant heating through living spaces. Compared to wood stoves and fireplaces which use convection to heat, masonry heaters use radiant heat that circulates naturally through the home, warming skin, objects and the air in a comfortable even heat. Generally, masonry heaters are fired for just a few hours using 25 to 45 pounds of wood, then allowed to transfer the heat from the masonry of the heater to the surrounding rooms. The soapstone or masonry retains heat yet will not burn to the touch nor overheat rooms. Because they are often located in the center of rooms, these heaters will include warming benches for seating and baking ovens on the side opposite the windowed door.

How Efficient are Masonry Heaters?
Masonry heaters burn wood cleanly with little ash and using small amounts of wood. They capture the BTUs of wood combustion and store it in the masonry body, releasing it slowly to warm the room. Europeans are ahead of the curve with masonry heaters as they are used quite extensively there and must meet strict emissions standards. The Environmental Protection Agency (EPA) has exempted masonry heaters from emissions guidelines, but local states and municipalities may refer to several other ways to meet local safety and emissions standards. The Canadian CSA B-415 efficiency standard is recognized by the EPA and recently the Masonry Heater Association worked with the CSA B-415 committee develop a method for evaluating masonry heaters for efficiency. In addition, Colorado has developed their Regulation #4 method for testing emissions to meet their code. Imported masonry heaters, such as Tuliviki imported from Finland have UL approval and pass all European standards.

What Other Factors Should Be Considered?
Masonry heaters are able to heat large spaces but are limited by their size to heat beyond a certain square footage. Placing them in central locations maximizes their ability to heat. The structures are heavy, and so will require good structural support. To maintain proper air flow a tall chimney is required to create the proper draft for clean burning. All of these specifications should be reviewed with the design experts at Katahdin Cedar Log Homes so that the home can support these requirements before plans are finalized.

Masonry Heater Resources
For expert assistance in developing a masonry heater for your Katahdin Cedar Log Home, consult the Masonry Heater Association of North America. Their organization ensures members are up to date on requirements and modern construction techniques. Their member directory can also identify masonry heater experts in your area.

Photos courtesy Masonry Heater Association of North America