Super Efficient Masonary Stove

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The Missouri Designed Masonry Stove
At last there is an energy efficient replacement for the popular, but energy inefficient English style fireplace.
This style fireplace or masonry stove is based on the very simple concept of storing heat in a series of brick
baffles for longer, slower release as opposed to sending heat up the chimney of the standard fireplace.
With imagination, these masonry stoves, sometimes referred to as "Russian" fireplaces, can be vefy attractive
and functional. Progressive home buyers and builders may want to consider one of these efficient units as a
substitute for the older inefficient open-style fireplaces. Innovative crafters can devise many ways to make these
units just as decorative as other heating units. Considering the long-term world energy situation, it makes sense
to utilize the best possible heating devices in your home.
The masonry stove is a highly efficient heating unit which has been used in Eastern Europe for hundreds of
years. Once widely used in the western and northern parts of the mid-west, lower cost heating units and more
convenient fuels ultimately resulted in the decline, and finally abandonment of these masonry stoves. High cost
fuels and the impending scarcity of oil and natural gas, have stimulated a renewed interest because of the lower
cost of operation compared to other types of fireplaces or fireplace inserts. This ninety (90) percent efficient
stove design was reintroduced by a Russian immigrant which accounts for the commonly used name of "Russian"
fireplace.
This masonry stove is based on the use of flue baffles made of brick, stone or adobe, that direct the hot flue
gases in an "S" shaped pattern. The serpentine pattern slows down the air speed and also increases the length
of the flow. Each additional square foot of masonry surface absorbs some of the heat from the flue gas until
maximum available temperature is reached. As the fire itself is allowed to bum out, the hot bricks slowly pass
their stored heat through the wall and into the living space as radiant heat. Each pound of brick will store 2/10
BTU of energy for each degree (Fahrenheit) rise in temperature. This is the reason a masonry stove is so efficient
and retains heat for long periods.
This slow, steady, low-level heat is very comfortable, much more so than a fan-driven, central heated, hot air
furnace. The appearance of this type fireplace is controlled mostly by the designer's imagination, time and skill
in constructing the unit. It is possible to design one of these units to resemble an English style fireplace, but
it adds greatly to the time, cost and complexity, and serves to perpetuate an appearance of an outdated fireplace
that was never well designed for home heating.
On a cold day, the standard widemouth deep firebox, English style, masonry fireplace will lose more furnace
heated air up the chimney than it generates from the fuel it bums. Under the best of conditions, the English
fireplace will waste ninety (90) percent of the fuel that it bums on a season long basis. By contrast the masonry
stove has been tested and found to deliver to the room, about ninety (90) percent of the heat generated from
the fuel that is consumed. Even the least efficient masonry stove designs have resulted in eighty (80) percent
of the heat delivered to the living space, compared to sixty (60) to sixty-five (65) percent for many of the
airtight modem wood stove designs.
The Missouri designed masonry stove, as shown in the drawings, will cost about the same amount as the
standard English fireplace, but will have a lower life cycle cost because it uses fuel so efficiently. One full
loading of the firebox of a masonry stove will keep the stove at comfortable temperatures for 23 to 36 hours.
These massive brick or masonry units work very well as part of the heat storage mass for passive solar heated
homes. The units can also be used as room dividers.
Masonry stoves are very well adapted to new homes where floor plans allow for the required extra space. They
can be adapted to many existing homes by locating the unit in an insulated basement or in the living room by
the use of reinforced masonry piers. In some cases, a slab on grade floor may carry the weight if properly
reinforced. These adaptations will increase the cost of the unit, but generally will be cost effective over time,
because of the fuel cost savings that result.
Some Reasons for Building a Masonry Stove
Advantages
The cost is similar to the English style fireplace.
Masonry stoves use much less fuel; sometimes up to thirty (30) percent less than the best steel stoves.
The units may be used as part of the mass heat storage for passive solar systems.
Masonry stoves provide more comfortable heat than hot air or baseboard heat.
Masonry stove owners report greater personal comfort at lower room temperatures.
When properly operated, these units have reduced creosote buildup.
Masonry stoves generate less pollution, by sending less fly ash and unburned gases up the chimney and
into the atmosphere.
The unit can be adapted for the heating of domestic hot water.
The unit can contain a built-in oven.
Masonry stoves can be designed to load fuel from either side or either end.
Residential floor plans may be designed to permit loading the unit from an isolated hall or mud room.
Masonry stoves costs only slightly more than a high quality stove and chimney.
Masonry stoves can be designed and situated to occupy less space than some of the larger radiant style
steel stoves because they can be set closer to walls, etc. (do not neglect safety clearances).
Disadvantages
01. Masonry stoves take up more room than most stoves or wall mounted fireplaces. However, by using
specialized firebrick or castable fire clay it may be possible to have a masonry stove with a 25" x 25"
exterior ornamental wall dimension.
02. The units may be difficult to retrofit to an existing residence.
03. Masonry stoves warm up slowly, unless a hot water radiator or oven has been designed into the unit.
04. Specialized masonry materials are difficult to find in some locales.
Construction of a Masonry Stove
The following pages will include years of accumulated construction and design ideas. The construction procedure
will be illustrated, starting with the reinforcement of the hearth pad.

To be continued...