Masonry heaters first appeared in Northern Europe in the early 16th century. Historically, they were used in the kitchen, combining a stove, oven and seating areas. Located in the center of the home, they were fired twice daily for the preparation of meals and heating. The heaters were in all homes regardless of social status; however they varied aesthetically from white wash clay to ornate masterpieces.
The heaters require only small amounts of fuel. Wood, a renewable resource, pellets made from corn husks or other agricultural waste bi-products can be used. Without the requirement for natural gas, oil or electricity to run, masonry heaters can save energy. When incorporated with well-insulated walls and roof, as well as components for controlling the summer sun, masonry heaters can allow a home to go off the grid.
In addition to energy savings, other benefits include a reduction in smoke and particulates associated with a typical fireplace as the closed system of the firebox and flue prevent the release of noxious elements. Compared to a forced air furnace system, the masonry heater creates less dust and the home does not require ducting which also helps reduce noise transmission. The heaters are aesthetically compatible with any home interior decor; however materials must be carefully chosen for heat resistance. The heaters can be multi-purpose and incorporate heated benches and bread ovens among other things. Additionally, they can be used as the heat source for a radiant floor heating system; however this requires an electrical energy source for pumps to circulate.
As with any heating system, there are also drawbacks to the masonry heaters. To work best, they must be centrally located within the home which can limit design flexibility for home layout. It is also recommended that other walls within the interior of the home are made of masonry so that they can absorb the heat and radiate it to adjacent rooms. This construction is more expensive and difficult to change once constructed. Unlike a furnace, the masonry heater must be manually stoked twice daily. This limits the ability of winter vacations unless assistance is provided. Traditionally the heaters require a master mason who has been specially trained. However, for the most intrepid of do-it-yourselfers, there are pre-manufactured kits available from several companies. Compared to other heating systems, they initial capital cost is expensive; the average cost ranges between $10,000 and $30,000 depending on size and complexity. The typical payback period for an average home is 10 years. It also takes many weeks to construct, which must be incorporated into the construction schedule.
Despite these drawbacks, the masonry heater is a suitable alternative for a home heating system in new construction. As the costs of natural gas and electricity continue to rise, the affordability and practicality of the heaters will only increase. For further information, follow the links below, or contact KHA Design to see how a masonry heater could be incorporated into your project.
1. Masonry Heater Association of North America
2. Cold Climate Housing Research Center
3. Masonry Stove Builders, Pre-Manufactured Kits from Ottawa
4. Temp-Cast Masonry Heater Planning Guide