Masonry Heaters

Masonry heaters are also known as "Russian," "Siberian," and "Finnish" fireplaces. They are well known for style, efficiency, clean combustion, safety, and the ability to store heat and release it slowly. They are common in Europe, and are gaining popularity in the United States.

A wide variety of masonry heater designs and styles are available. Larger models resemble conventional fireplaces and may cover an entire wall. Smaller models take up about as much space as a wood or pellet stove. They can be custom-built or purchased as prefabricated units. All designs have three basic components: a firebox, a large masonry mass, and long and convoluted smoke channels that run through the masonry mass. Their fireboxes are lined with firebrick, refractory concrete, or similar materials that can handle temperatures of over 2,000o F (1,093o C).

Most are intended for burning wood, but they were historically designed to burn almost any type of solid fuel. There are also several companies that make units that use natural gas or propane. The solid fuel (wood) burning types use a small, intense fire that is lit once or twice a day, depending on heating requirements. For all types, as the hot combustion gases from the fire pass through the network of smoke channels, the masonry absorbs much of the heat, which then is radiated slowly and steadily into the home over the next 12 to 20 hours.

Wood burning masonry heaters are much more efficient and clean burning than conventional wood burning fireplaces. A combustion efficiency of close to 90% is common (as opposed to 60% for a regular woodstove and 10% for a regular fireplace.) The relatively small, but intense fire also results in very little air pollution and very little creosote buildup in the chimney. Because most of the heat from the fuel is transferred to the masonry and slowly released into the room over the day, this type of heater does not need to be loaded with fuel as often as other types of wood heating appliances. In addition, if the masonry heater is built where sunlight can directly shine on it in the winter, the heater will absorb the sun's heat and release it slowly into the room.

Although masonry heaters are efficient and clean burning, they have some disadvantages. Unlike conventional wood stoves and fireplaces, they cannot provide heat quickly from a "cold start." They are also relatively expensive. Some large designs may cost $5,000 or more. Plans and kits are available, but they are not easy do-it-yourself projects and require experience in working with masonry.

For more information on masonry heaters contact the:

Masonry Heater Association of North America (MHA)
1252 Stock Farm Road
Randolph, VT 05060
Phone: (802) 728-5896 Fax: (802) 728-6004
World Wide Web:
The MHA provides information on masonry heaters, and will help you locate sources of masonry heaters and installers in specific regions of the country. Their website has a large amount of information on this subject.

EREC is operated by NCI Information Systems, Inc. for the National Renewable Energy Laboratory/U.S. Department of Energy. The content of this brief is based on information known to EREC at the time of prepartion. No recommendation or endorsement of any non-US Government product or service is implied if mentioned by EREC.

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Energy Efficiency and Renewable Energy Clearinghouse (EREC)
P.O. Box 3048 Merrifield, VA 22116
Voice (USA only): 800-DOE-EREC (363-3732)

This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof.

Courtesy of mha-net - The Masonry Heater Information Site

Check out our Heaters Buyer's Guide for more information on selecting the perfect heater.