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Are russian fireplaces and other masonry heaters a good deal?
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Masonry stoves appear to be more effective - why aren't they more popular?
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heat has no intelligence, bigger it's the mass bigger it's thermal inertia, if I imagine a masonry stove with one meter walls I can easily deduce that the heat that will arrive externally will be very little. The question, of the low temperature of the chimney is because many Europeans do not use well-seasoned wood!I looked this up, and there are masonry stoves with more appropriate output:
Max load is about 50 lbs. Assume 7000 BTUs per lbs, and a (generous...) efficiency of 90%, that means 315,000 BTUs going into the room. If (...) that's spread over 12 hrs, that averages to 26,000 BTUs per hour.
Of course there's no control, and I don't know how even the heat release into the room is within the burn+cool cycle.
But there are masonry stoves that can do decent BTU production.
These are very different from the lighter build it yourself package kits one finds online. I think the big ones (as in half a small European room-sized, with bed alcoves in/on it, different rooms on different sides of the stove), can do this, i.e. more than the 15,000 BTU per hour.
Okay well I am talking from personal experience, not sure who has had a masonry heater or not on here. I heated a 1600 ft home solely with it outside Ottawa, Canada and it gets pretty cold there. House maintained a comfortable 68-70 degrees and I only burnt a few cords a year. That to me is efficient and having owned multiple wood stoves on cold climates, the masonry heater is far better.
But did you compare to a wood stove *in that same home*?
If not, it's impossible to draw such a conclusion.
In the end, even if a masonry stove is 100% efficient, that would only use about 25% less wood than a modern wood stove. (And no stove is 100% efficient.)
If not, it's impossible to draw such a conclusion.
In the end, even if a masonry stove is 100% efficient, that would only use about 25% less wood than a modern wood stove. (And no stove is 100% efficient.)
And yet that is precisely how the parents of my Ukrainian friends heat their home.
Heat can only go two ways: into the room or out the flue. Also for thick walled models that holds. If very little would get into the home, that means that all goes out the flue (and that is not the case) after the mass has been "charged up" with heat.
Not only a wood stove. If it's being compared to an old pre epa stove like many do it isn't a fair comparison
I’m pretty surprised that nobody has bridged the gap between an iron/steel stove and masonry stoves. It should be pretty easy to cast sections to make stacking a very easy way to add thermal mass.
Is your stove cooking you out of your room? Let’s add some mass to slow down the heat transfer a bit. Want the heat faster? Let’s remove some mass to make the stove more like a regular steel stove.
This sort of setup could easily be taylored to what the floor was designed to hold also.
Is your stove cooking you out of your room? Let’s add some mass to slow down the heat transfer a bit. Want the heat faster? Let’s remove some mass to make the stove more like a regular steel stove.
This sort of setup could easily be taylored to what the floor was designed to hold also.
The problem is that the stove and exhaust really needs to be designed to take advantage of the mass. Your idea could work to an extent but never like a real masonry heater. Plus I have no idea how they would test and certify something like that
I figured as long as the firebox wasn’t altered it’d roughly be the same as adding cast iron cladding to the stove.
EbS-P
Minister of Fire
There was a paper posted on heath that looked at the efficiency of masonry heaters. Here is quick Google result. 80%.
I don’t see how the extra cost of construction today would ever pay off vs a an 80% efficient woodstove. They need cleaned too. Cleaning a woodstove is simple and fast. Cleaning out a masonry heater would not be a simple.
Let’s assume best case we can save 10 % on your cost of wood and you buy it at $300 a cord and burn 3 cords a year. That is a savings of 100$. At today’s materials cost and labor I imagine a masonry heater install is $20k. Let’s call a stove install $10k. So the $10k dollar difference would take 100 years to make it more fair let’s include the cost of a catalyst every 5 years and assume the stove has a 30 year life. That effectively makes comparison equally assuming your masonry heater has a 60+ year lifespan which is reasonable.
But you probably won’t live in your home with a masonry heater for 60 years.
I don’t see how the extra cost of construction today would ever pay off vs a an 80% efficient woodstove. They need cleaned too. Cleaning a woodstove is simple and fast. Cleaning out a masonry heater would not be a simple.
Let’s assume best case we can save 10 % on your cost of wood and you buy it at $300 a cord and burn 3 cords a year. That is a savings of 100$. At today’s materials cost and labor I imagine a masonry heater install is $20k. Let’s call a stove install $10k. So the $10k dollar difference would take 100 years to make it more fair let’s include the cost of a catalyst every 5 years and assume the stove has a 30 year life. That effectively makes comparison equally assuming your masonry heater has a 60+ year lifespan which is reasonable.
But you probably won’t live in your home with a masonry heater for 60 years.
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Oh it would be fine in one configuration. The issue is with the adjustability. It would have to be tested in each configuration
A well built masonry heater will last indefinitely. But there will be maintenance like rebuilding the firebox occasionally etc
EbS-P
Minister of Fire
When it's a complete product you buy not a site built unit. Now I'm not sure how much on site assembly qualities as site built though
I have a strong curiosity about wood burning for heating. Like you I did research. I also wondered why masonry heaters weren't more popular in North America as compared to Europe and Asia. I built one after intense study, and also hanging around and pestering some MH builders. I believe we have an immediate gratification mentality here - we want to do things now. Wood stoves are now. The Europeans/Asians think differently, i.e. more long-term. Masonry Heaters are more of a long-term approach. But there are more reasons.
Most of the USA is moderate in temperature (the lower Midwest to southward). So heating is not such a big deal. Wood stoves are cheaper, more portable, and lighter - so a quick wood burning gratification. In France, England, and Southern Europe there are less MHs (they are like most of USA). But once you move up into central and northern areas, MHs become more common, especially in the Nordic countries. Ignorance on how to build these things is also an issue.
It is strange how in North America fireplaces have been imbedded into our culture, into our way of living. Fireplaces aren't much for heating. Yet fireplaces aren't much different than MHs in some respects - they both require foundations, and they both use similar materials - it is just the arrangement of these materials that is different. And yet fireplaces are common. The masons here know how to build fireplaces so that is what they build (except in Oregon - outlawed
).
The distance between MHs and wood stoves can become blurry sometimes. Block off plates, changing the direction of the gas flow, adding heavy firebricks, and even catalytic combustors are wood stove concepts that MHs do too. The chamber above the firebox in a MH gets really hot so it acts like a catalytic combustor - this makes MHs very efficient (and hybrid woodstoves, too).
It would be a good future idea for companies to employ more mass designs in there hybrid wood stoves - say ones that weigh 2,000 lbs yet force the exhaust to take a longer path out before exiting. This exhaust could also be hit by a catalytic combustor (and maybe some sort of scrubber). The Germans are hooking in O2 sensors to 'machine brains' in their kachelofens (MHs) so as to get even more efficiency in their burns. Thus the air in the fire's burn is changing throughout the burn.
Most of the USA is moderate in temperature (the lower Midwest to southward). So heating is not such a big deal. Wood stoves are cheaper, more portable, and lighter - so a quick wood burning gratification. In France, England, and Southern Europe there are less MHs (they are like most of USA). But once you move up into central and northern areas, MHs become more common, especially in the Nordic countries. Ignorance on how to build these things is also an issue.
It is strange how in North America fireplaces have been imbedded into our culture, into our way of living. Fireplaces aren't much for heating. Yet fireplaces aren't much different than MHs in some respects - they both require foundations, and they both use similar materials - it is just the arrangement of these materials that is different. And yet fireplaces are common. The masons here know how to build fireplaces so that is what they build (except in Oregon - outlawed
).The distance between MHs and wood stoves can become blurry sometimes. Block off plates, changing the direction of the gas flow, adding heavy firebricks, and even catalytic combustors are wood stove concepts that MHs do too. The chamber above the firebox in a MH gets really hot so it acts like a catalytic combustor - this makes MHs very efficient (and hybrid woodstoves, too).
It would be a good future idea for companies to employ more mass designs in there hybrid wood stoves - say ones that weigh 2,000 lbs yet force the exhaust to take a longer path out before exiting. This exhaust could also be hit by a catalytic combustor (and maybe some sort of scrubber). The Germans are hooking in O2 sensors to 'machine brains' in their kachelofens (MHs) so as to get even more efficiency in their burns. Thus the air in the fire's burn is changing throughout the burn.
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I have a MH heating my house. It’s not a masonry heater though, it’s a mass heater. It’s not a large one as far as poundage, but does have some advantages. It’s a Switzer gasifier wood fired boiler with integrated water storage that heats approximately 7,000 plus pounds of metal and water. Unlike a masonry heater, though, I can control the heat output by pumping or not pumping the water somewhere.
Just had to throw that in here. 😁 A masonry heat actually intrigues me, but it wouldn’t work in our climate here in Kansas.
Just had to throw that in here. 😁 A masonry heat actually intrigues me, but it wouldn’t work in our climate here in Kansas.
my grandparents also used an open fireplace to heat themselves, the problem is that current houses tend to be much larger and this type of product is unable to transmit enough heat, even if they stay hot for hours, the power is low.
Also considering the costs, It's a very risky investment
Sure. I deconstructed the masonry heater and threw in a wood stove for fun. My opinion is based on having a masonry heater designed specifically for the custom home build I did. Frankly wood heat is not the best heat from an efficiency perspective if that is what one is seeking but it’s a nice comfortable heat that if one has their own source of wood, makes it more price competitive and self sufficient.
Have you had a masonry heater yourself?
I’ll ask have you had a masonry heater? I am expressing my opinion and truly like them. Are they the best heat period, not from an efficiency perspective and that goes for pretty much all
Wood heaters.
Had one in my home no. Spent time in homes with them. Yes. They are great heaters I have absolutely nothing against them and if I were building a house I would definitely consider one. I just don't see the wood savings many claim to be possible
I have fired one (under supervision) when staying in a home in Northern Europe. But have no comparison to what an efficient wood stove would do in that home.
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EbS-P
Minister of Fire
I do think the radiant heat of a large multi sided MH could feel warmer when you are near the heater. I can walk my my fireplace 12-18 hours after a hot fire and see the stove temp 100-115 but still feel the warmth.
I think a carefully designed MH could have radiant surfaces in multiple rooms. BUT a true MH as a retro fit is not cost effective. As new construction why would I chose MH over a wood furnace tied into a heatpump/ac unit. There are few locations now that I would build without AC in the U.S.
I don’t see MH as cost effective. Technically has improved in x00 of yeas to the point there are better options.
I think a carefully designed MH could have radiant surfaces in multiple rooms. BUT a true MH as a retro fit is not cost effective. As new construction why would I chose MH over a wood furnace tied into a heatpump/ac unit. There are few locations now that I would build without AC in the U.S.
I don’t see MH as cost effective. Technically has improved in x00 of yeas to the point there are better options.
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