The history of the Kachelofen spans more than eight centuries, from the medieval tiled stoves of Alsace and Switzerland to the Gothic masterpieces of Salzburg. What follows is the full history of the Kachelofen, the tiled masonry stove of German-speaking Europe, and what it still teaches anyone building one today.
By Eric Moshier – Certified Heater Mason, Third-Generation Mason, MHA Technical Committee Member, ASTM E1602 Masonry Heater Group Member
The Kachelofen is the tiled masonry stove of German-speaking Europe, and it is one of the oldest continuously built heating appliances in the world. Solid Rock Masonry LLC of Duluth, Minnesota builds Kachelofen, kakelugn, Finnish contraflow heaters, Russian bell heaters, and wood-fired bake ovens for clients across the United States. Owner Eric Moshier is a Certified Heater Mason and a member of the ASTM E1602 masonry heater standards committee. A Kachelofen is a radiant heat storage appliance: it burns a small, hot, fast fire for 2 to 3 hours, absorbs that energy into a heavy masonry core, and radiates it back into the room for the next 12 to 24 hours. The earliest ceramic stove tiles yet found date to the 8th and 9th centuries, in Alsace, Baden-Wuerttemberg, and northwestern Switzerland. The oldest securely dated tiled stove was excavated at Winterthur, Switzerland, and dates to 1208. What follows is the history of the Kachelofen across Germany, Austria, Switzerland, and northern Italy, and what it still has to teach anyone building one today. Site-built masonry heaters run $30,000 to $40,000.
What is a Kachelofen?
Kachel means tile. Ofen means stove or oven. A Kachelofen is a stove faced in ceramic tile, but the tile is the least important part of it. What matters is the mass behind the tile and the path the smoke takes to get out.
Burn a fire in an open fireplace and most of the heat goes straight up the chimney. Burn the same fire inside a masonry heater and the hot flue gas is forced to travel through a long internal path, giving up its heat to the masonry at every turn. By the time the gas reaches the chimney it is comparatively cool, and the energy that was in the wood is now stored in several thousand pounds of brick and tile. The stove then radiates that heat back into the room, gently, for the rest of the day.
This is a heat storage appliance, not a heat production appliance. That distinction is the whole history of the thing, and it is still the single most misunderstood point about masonry heaters today. Read more about how masonry heaters work.
Where did the Kachelofen come from?
Nobody built the first Kachelofen on purpose. It emerged.
Historians believe the ancestors of the Kachelofen were the bread ovens and vaulted hearths already built into houses in cold regions. At some point in the early medieval period, somebody began pressing ceramic pots, open end outward, into the clay dome of one of those ovens.
The reason was simple and physical. A clay dome radiates heat from its surface. Push a hollow pot into that dome and you have just increased the surface area available to radiate. Push in dozens of them and you have a dome bristling with little ceramic cups, each one throwing heat into the room. Those pots are what we now call Becherkacheln, beaker tiles, and they are the ancestors of every stove tile that followed.
The earliest ceramic objects that archaeologists are willing to call stove tiles come from Alsace, from Baden-Wuerttemberg, and from northwestern Switzerland, and they date to the 8th and 9th centuries. These belonged to front-fired stoves, set into the corner of a room and fed from the front.
The invention that changed the European house
Then, probably in the course of the 11th century, somebody made a change that is easy to describe and hard to overstate.
They moved the firebox door to the back of the stove and pushed it through the wall.
Now the stove stood in the living room, but it was fed from the kitchen on the other side of the wall. The smoke went back out through the firing opening into the kitchen, which was already a smoke-filled room with an open hearth, the schwarze Kueche, the black kitchen. The living room got the heat and none of the smoke.
This is the Hinterlader, the rear-loading stove, and it is the reason the Stube exists. The Stube was the heated, smoke-free room of the medieval house, and it became the center of European domestic life: where the family ate, worked, spun, taught, and slept warm. It was not possible before the tiled stove, and it arrived with it.
A heating appliance created a room. That room then organized the house around itself for the next seven hundred years.
Within roughly a century, tiled stoves were standing in the Stuben of the North German Hanseatic cities. By about 1200 the Kachelofen was standard equipment in castles, in monasteries, and in the townhouses of the wealthy. Early on it was a luxury: the finds suggest it belonged to monasteries, to the nobility, and to the patrician class. Ordinary houses kept their plain masonry stoves for a long time yet.
The oldest Kachelofen we can actually date
Excavated at Winterthur, in Switzerland: a stove of the year 1208. It was built the way all early Kachelofen were built, of stove clay and beaker tiles.
That date is worth holding onto. The Swedish kakelugn, the Finnish contraflow, and the Russian bell heater are all later developments. The tiled masonry stove of the Alps and the German-speaking lands is the older tradition, and much of what came after grew out of it. Read about the Swedish kakelugn.
The Hafner: the guild that made the stove and set it
The man who made the tiles also built the stove. He was called the Hafner, and in most of the Kachelofen region he was both potter and stove-setter, Ofensetzer, right into the 19th and 20th centuries.
That is unusual, and it explains a great deal about how these stoves look. There was no supplier, no catalogue, no separation between the man who threw the clay and the man who laid the masonry. One craftsman shaped the tile, glazed it, fired it, and then went to the house and built the stove out of it. When you see a 16th century Kachelofen that is coherent from its base to its crown, that coherence is because one man held the whole thing in his head.
We still work the same way, in the sense that matters. On our own round tile stoves the tile has to be made for the stove, not selected from a shelf.
From pot tile to picture tile
The beaker tile is a cup. It works, but there is not much you can do with it artistically.
From the 14th century the Hafner began making relief-decorated tiles, and the Kachelofen stopped being only a heater. The Becherkachel gave way to the Blattkachel, the panel tile, which presented a flat or shallow-relief face to the room and could carry an image. Once the surface could carry an image, everything followed: saints, coats of arms, biblical scenes, allegories, hunting scenes, portraits of rulers, the whole visual culture of late medieval and Renaissance Europe, fired into the wall of the family room.
The vocabulary of tile types multiplied accordingly. Becherkacheln, Blattkacheln, Napfkacheln, Nischenkacheln, Eckkacheln for the corners, Gesimskacheln for the cornices, Kranzkacheln and Bekroenungskacheln for the crown. A large stove might use a dozen types, each one made for its exact position.
The Renaissance: Nuremberg and Winterthur
In the 16th and 17th centuries two cities became the great Hafner centers north of the Alps: Nuremberg, and Winterthur, where the Pfau family worked.
Winterthur tiles are the ones most people picture without knowing it: painted in blue and manganese on a white tin glaze, crowded with narrative scenes, framed like little windows into a story. A Winterthur stove is a book you can warm your hands on.
The Gothic and Renaissance stoves of this period are also, technically, still primitive. They were beautiful, they were enormously expensive, and they were not efficient. Almost all the real thermal engineering was still to come.
Austria: Salzburg, and the finest Gothic stove in the world
Go to the Hohensalzburg fortress above Salzburg, into the Goldene Stube, the Golden Chamber, and you will find a tiled stove made in 1501 for Archbishop Leonhard von Keutschach.
It is generally considered the finest Gothic Kachelofen in existence. It is covered in colored tiles bearing saints, evangelists, and heraldry, and the room around it has been essentially unchanged since 1502. It is not a reconstruction. It is the thing itself, still standing where it was built, more than five hundred years later.
It is also a reminder of what a Kachelofen was to a man like an archbishop: not a household appliance but a statement of power, made by the best craftsman he could find, in the most important room he had.
Beyond Salzburg, the Austrian tradition runs deep in the Tyrol, where Hafnerkunst, the art of the stove-maker, is a documented craft with its own scholarship. The Tyrolean Stubenofen typically incorporates the Ofenbank, the stove bench: a heated seat built into the body of the stove itself. In an Alpine winter, that bench is the warmest and most valuable square meter in the house, and everyone in the family knows it.
Switzerland: the Kunst and the heated bench
The Swiss and the Black Forest builders took the bench idea and pushed it further, into something called the Kunst.
The Kunst, sometimes Chunst or Chouscht in dialect, was a heated masonry bench with its own flue system, built onto the stove and fired from the kitchen range. It solved a specific problem: the kitchen range needed a way to get rid of its exhaust, and running that exhaust through a bench in the living room turned waste heat into a warm place to sit.
The historic Kunst benches were built high, because builders at the time did not yet trust themselves to route flue gas downward, and the ranges they connected to were low. They were so high that a wooden footstool was often needed to climb onto them.
Modern Swiss Kachelkunst has separated from the stove and become its own system: it heats and it cooks, and it remains popular in Switzerland and southern Baden-Wuerttemberg to this day.
If you have wondered why so many masonry heaters we build have a bench on them, this is where the bench comes from. It is not a design flourish. It is six hundred years old and it earned its place.
Italy: the stube of the Alpine valleys
The Kachelofen is usually described as a German-speaking phenomenon, and it mostly is. But the map does not stop at a language border. It stops at a mountain range, and then it goes over it.
The Kachelofen tradition extended into northern Italy: into South Tyrol and Trentino, into the Italian-speaking valleys of the Alps, and into Lombardy. The stube of an Alto Adige farmhouse, with its wood-lined walls and its tiled stove in the corner, is the same room as a Tyrolean Stube, because until 1919 it was in the same country. The tradition is Alpine before it is national.
You can see it in the surviving grand rooms of the Italian Alpine towns. The Casa Pestalozzi in Chiavenna, in the province of Sondrio, has a state room with a tiled stove. The Casa Pellanda in Biasca, in Italian-speaking Ticino, dated 1587, has another. These are Italian rooms with Alpine stoves in them, and there is no contradiction.
Baroque and Rococo: the stove becomes furniture
Beginning in the Baroque, a new technique called Ueberschlagtechnik allowed the Hafner to make much larger and more freely formed tiles and stove components. The stove could now be sculpted rather than assembled from small repeating units.
What followed was the most beautiful century of the Kachelofen and, arguably, the silliest. The Rococo stoves of the great manufactories, such as the Frisching works in Bern, are white confections painted in rose and green, curved like porcelain, standing in a corner of a salon looking less like a heater than like a piece of the wall that has grown ambitious.
They are magnificent. They are also a reminder that the aesthetic history and the technical history of this stove ran on separate tracks for a very long time. The tile got prettier for four hundred years while the thermodynamics barely moved.
The 18th century: the revolution nobody talks about
Here is where the Kachelofen actually becomes the appliance we recognize.
Until the 18th century, most Kachelofen were fired from the kitchen with the door open, and the smoke simply drifted back out into the kitchen and up the open hearth, or out through gaps in the roof. The stove worked by trapping heat in its upper body and radiating it. Better than an open fire, certainly. Still very inefficient.
Two things changed. First, Europe was running out of wood. Deforestation made fuel expensive, and expensive fuel makes engineers of people. In the late 17th and 18th centuries serious attention turned to the Sparofen, the wood-saving stove. Frederick the Great of Prussia went so far as to run a competition for the best wood-saving stove design. Some of the entries proposed stoves that ran through two storeys of a house.
Second, and decisively, stoves began to be connected directly to a chimney.
That connection is what made internal flue channels possible. Once you have a chimney pulling on the stove, you can make the flue gas do work before you let it go. You can run it up. You can run it back down, which is the counter-intuitive part, and which took builders a long time to trust: the Sturzzug, the downdraft channel. You can send it up and down and up again, stripping heat out at every pass.
That is the moment the masonry heater becomes what it is. Everything we build today, the Swedish five-run channel system, the Finnish contraflow, the Russian bell, is a descendant of that 18th century realization that flue gas can be made to give up almost everything it has before it reaches the sky.
The 19th and 20th centuries: coal, convection, and standards
Coal arrived in the 19th century and changed the stove again. A coal fire holds a hot bed of embers far longer than a wood fire, so the direct contact between fire and a huge ceramic mass became less essential. Fireboxes got smaller. Grates and ash boxes appeared. Cast iron inserts appeared, containing all the moving parts, so a firebox could be repaired without dismantling the entire stove.
Air circulating around those inserts gave rise to the Warmluftofen, the warm-air Kachelofen: fast to heat, convective rather than radiant, with the ceramic shell storing a portion of the heat. It could warm a room quickly and even duct warm air to other rooms and other floors.
In 1925, the craft rules and the accumulated experience of centuries were written down as DIN standards for the Kachelofen. DIN 1289, covering firing doors, dates to 1928 and is still valid today. The standards classified stoves as light, medium, or heavy construction depending on the wall thickness, and gave planning values for heating capacity, mass, and storage duration.
This is the point where the Kachelofen enters the modern engineering world, and it is the direct ancestor of the standard we work to in the United States now. Masonry heater building codes, ASTM E1602 and IRC R1002.
Grundofen, Warmluftofen, Kombiofen: the three types
Modern German-speaking practice recognizes three basic forms, and the distinction matters if you are choosing one.
Grundofen
The Grundofen is the true masonry heater: built on site by hand, with a firebox and ceramic flue channels behind it, and no metal insert. It is a Zeitbrandofen, a time-burn stove. You burn a defined charge of wood, fast and hot, and the heat is stored in refractory and released slowly. Depending on its mass, it runs 8, 12, or 24 hours between firings. This is what we build.
Warmluftofen
The Warmluftofen works by convection. Room air enters at the base, is heated by a cast iron insert, and rises back into the room. Sixty to eighty percent of its output is convective, the rest radiant. It heats a room fast. It also stirs dust through a very hot metal surface, which is a real drawback that the German literature is candid about.
Kombiofen
The Kombiofen combines a modern insert with masonry flue channels. You get fast heat from the insert, within 15 or 20 minutes, and 6 to 12 hours of storage from the ceramic channels behind it. It is a reasonable compromise, and a great many contemporary European stoves are built this way.
If you want the deepest, longest, gentlest heat, you want a Grundofen. That is the tradition that runs unbroken from the 1208 stove at Winterthur to the heaters we build in Minnesota.
What the Kachelofen shares with the kakelugn
They are cousins. Both are tile-faced masonry heaters. Both burn a fast fire and store the heat.
The differences are national and formal. The Kachelofen of Germany and Austria tends to be broad, blocky, and horizontal, and it frequently incorporates a bench. The Swedish kakelugn, developed from 1767 by Carl Johan Cronstedt and Fabian Wrede at the direction of a Swedish state facing a firewood crisis, is typically tall, narrow, round, and vertical, with a five-run channel system stacked into a very small footprint.
Both were, in the end, answers to the same question, asked in different countries in different centuries: how do we stop burning our forests to stay warm? More on the kakelugn and the Swedish tradition.
Building a Kachelofen in America today
We build Kachelofen, and we build them to be legal here. The whole history of the Kachelofen sits behind every one we build.
The code path for a masonry heater in the United States is IRC Section R1002, which references ASTM E1602, the standard practice for construction of solid fuel burning masonry heaters. Eric Moshier sits on the ASTM E1602 committee. Firebox masonry thicknesses and clearances to combustibles are set by that standard, and they are the first thing an inspector will measure.
A Kachelofen needs a real foundation: 4,500 psi concrete or better, 8 inches deep, with 1/2-inch rebar at 12 inches on center. It needs to be sized against your actual heat loss, not against a peak hourly BTU figure from a Manual J calculation. A masonry heater releases its output over 12 to 24 hours, so those two numbers are not interchangeable, and sizing one against the other will lead you to build something far larger than you need. Start with the free calculator at LoadCalc.net.
And it needs tile. Real tile, made for the stove. On our round tile stoves that tile is made by hand in Duluth by Sharon Moen of Falconfire Pottery, one tile at a time, exactly the way a Hafner would have done it in Winterthur in 1580.
We also teach these stoves. At the Masonry Heater Association annual meeting at Wild Acres, we co-taught a build of the Steubenofen shown below with Austrian architect Stefan Polatschek. We taught it for its history: the Steubenofen was among the first masonry heaters ever built in Europe.
Frequently asked questions about Kachelofen history
How old is the Kachelofen?
In the history of the Kachelofen, the earliest ceramic stove tiles found so far date to the 8th and 9th centuries, in Alsace, Baden-Wuerttemberg, and northwestern Switzerland. The oldest securely dated tiled stove was excavated at Winterthur, Switzerland, and dates to 1208. The form has been built continuously for over eight hundred years.
What is the difference between a Kachelofen and a kakelugn?
Both are tile-faced masonry heaters. The Kachelofen is the German and Austrian tradition: typically broader, often with a heated bench. The kakelugn is the Swedish tradition, dating from 1767: typically tall, round, and vertical, with a five-run channel system in a compact footprint.
What is a Grundofen?
A Grundofen is a site-built masonry heater with a firebox and ceramic flue channels and no metal insert. It burns a defined charge of wood fast and hot and releases the stored heat over 8 to 24 hours depending on its mass. It is the purest form of the Kachelofen and the one we build.
Why does a Kachelofen have a bench?
The heated bench, the Ofenbank in Austria and the Kunst in Switzerland and the Black Forest, is a centuries-old feature. It puts a warm seat directly against the thermal mass of the stove. In an Alpine winter it was the most valuable seat in the house, and it still is.
How long does a Kachelofen burn?
You fire it for 2 to 3 hours. It then radiates heat for the next 12 to 24 hours. There is no reloading through the night.
Who built the historic Kachelofen?
The Hafner, a craftsman who was both potter and stove-setter. He made the tiles and then built the stove out of them. In most regions this remained a single trade into the 19th and 20th centuries. Nuremberg and Winterthur, home to the Pfau family, were the two most important Hafner centers north of the Alps in the 16th and 17th centuries.
Where is the finest historic Kachelofen?
The Gothic tiled stove of 1501 in the Goldene Stube of the Hohensalzburg fortress in Salzburg, Austria, made for Archbishop Leonhard von Keutschach, is widely regarded as the finest Gothic Kachelofen in the world. The room around it is essentially unchanged since 1502.
Can I have a Kachelofen built in the United States?
Yes. We build them nationwide from Duluth, Minnesota, engineered to satisfy IRC Section R1002 and ASTM E1602. Site-built masonry heaters run $30,000 to $40,000 depending on size, tile work, and site conditions.
Can a Kachelofen have a bake oven?
Yes. Historically many did, and the Backroehre, the baking tube or oven, was standard in many regions. We build both black ovens, which are directly fired, and white ovens, which are heated indirectly.
Build one
There is a straight line from a potter in Winterthur in 1208, pressing clay beakers into the dome of a stove to throw a little more heat into the room, to a Certified Heater Mason in Minnesota in 2026 laying firebrick to a standard he helped write. It is the same craft and the same physics. The tile changed. The problem did not.
If you want a Kachelofen, we would like to talk about it. Start with our planning process, our planning guide, or our custom masonry heaters.
Solid Rock Masonry LLC
5347 Howard Gnesen Road, Duluth, MN 55803
218-343-2978
eric@solidrockmasonry.com