how do we tell more people about rocket mass heaters

paul wheaton wrote:
And when there is a big "oh shit!" about heat, can we at least get a little brain space about rocket mass heaters?

daniel thomas allen wrote:I am trying to pitch a story about this to Business Insider where I work. Would anyone here be able to help introduce me to people living in typical suburban homes that have installed one? Or even better, someone living in Europe where energy rationing is coming and shit is about to get REAL!

Back in February of 2021 I have a oh shit moment. Power and gas supplies in Kansas could be cut and it was -10 F outside. I had no fireplace but my parents did. But how would I protect my water lines from the cold was something I could not figure out. I did not lose gas or power to my home that winter. Needless to say I am not a big fan of how all that when down.  Since then I have had an idea of making a emergency rocket mass heater. Just an idea with no plans but a name.

Watching all of the Better Wood Heat: DIY Rocket Mass Heaters DVD. I see that many hands make the work of building easier. Is there a video of one person building a rocket mass heater by themselves?

On the topic of codes, local governments and insurance. For me the biggest issue would be home insurance. How would you explain to your insurance what a rocket mass heater does and how would they treat it? Next is codes and local governments.  The code enforcement in my area is more about outside of a house and not the inside. If you invite a code enforcement person in then you would need to be concerned. I call this the vampire rule.

Last points.
I would like a rocket mass heater in my home?
Hell yes!
What is stopping me from building one?
Getting people to help me build a heater and getting a highly knowledgeable person to oversee the building. Next talking to my insurance about coverage. Last codes and local government which I think could be a long process and again I would need a highly knowledgeable person to help out.

I think if you have five to ten builds in a city in a year, this would be a big help in getting the word out.

Wow! Lot of good ideas here, a lot of good information. I think what you need is a plan -- a marketing plan and a strategic plan, so that you know the path you want to take to get more people interested in making their own rocket mass heater or from a commercial point of view, installing one for people. You're on the right track. I'm a retired direct marketer, maybe I can help.

More later.

P.S. I'm in the camp that I would pay to have someone install a RMH for me. There's not a snowball's chance in hell that I could build one for myself.

How do we tell more people about Rocket Mass Heaters.

Good Question.  How do most people take their information these days?   With their cell phones?  Watching videos?

I'd have to say it's a safe bet that if someone created a short film based on the RMH's known advantages, along with an associated website that could be used for dissemination of more in-depth information, you might then have a vehicle that could make the rounds globally via viral dispersion.

It would have to have superb videography and editing, as well as top notch narration.  Think on the level of a National Geographic Nature special.

I would think most, if not many who are looking for something like the RMH have already found it, but maybe if we approached it as a "Docutainment" it might cross the paths of more people.

Perhaps start with talking about heating mass instead of air.   Why heat mass instead of air?  Air holds very little heat so when you use a lot of energy to heat it up it quickly gets cold again. Mass holds a lot of heat and it takes a long time to get cold.   If you go from one space to another where the air is the same temperature but one has cold walls and the other has warm walls You will immediately feel warmer with warm walls. It is called radiant heating.

But how do you get that mass of walls, floors. ceilings warm inexpensively?

 There is a verry adaptable wood rocket burning stove system that concentrates on burning the wood completely then capturing the maximum of the heat in mass to be radiated later.  It is called a Rocket Mass  Heater because of these 2 basic principles: It burns wood fast and completely like a rocket and it stores heat in mass instead of trying to heat air.

But burning wood is adding to the pollution and global warming.

The wood comes from taking CO2 out of the atmosphere and it eventually breaks down  and returns to the air anyway.  A rocket burner returns it in the least polluting way  and avoids producing heat from polluting sources.

Any other questions or shall we start researching what kind of mass heating will work for your circumstances.

Why it has not become imperative for me to build a RMH even though I love the concept and want one in my home:

1.  The R word.

When I first discovered the idea (here), the name Rocket made me think of science fair projects.   I loved the experimental approaches being taken, and yet that made it seem like the whole idea was still in the experimental stages. What I saw were people with more skills than I have playing with fire and having good results. That did not connect with me wanting this thing named like a flame thrower in my home.  I like my home.   I do not want a rocket combusting inside of my home.  Especially not a rocket that I built.  It's one thing to have a loaf of bread not come out, it's a whole other level to not have a fire (danger), smoke (danger, damage), construction-level (mess, skill, and some expense) project not work out.

For me, if this "technology" had been branded less as a new great idea and more as a refinement of a very old and effective method, I would have been less hesitant to approach it.

Upon further exposure to the idea and the history of development of mass heaters,  I realized I wanted to do this in my house.   But:

2.  Permits (?) -- As Kenneth talked about

3.  Timing.  I had just finished rebuilding.   If I had seen this before starting, I would have put in a RMH, and like Trace said,  I'd be selling people on it like crazy just by having an example.

4.  Safety.   Even with all the fine examples I've seen,  I still feel unconvinced that I would be safely burning anything inside my house using a thing that I've built. All sorts of "What if" questions end with the scenario that I Could Lose My Home and/or burn us up in our sleep, smoke us out, or invisible gas poison us,  all because I thought I could fly close to the sun.  Not rational.   Lizard brain stuff.   But it's there.

5.  Responsibility.   I want someone else to be responsible for researching and building ways to keep me safe from a fire.  I like tools, but I don't want to have all the tools needed to measure such things.  So I want manufactured assurances that no other lemmings have died from RMH use.

I wonder if you're dealing with a strong survival instinct when you meet with resistance.

Aesthetics ARE important - to many. Not to everyone, but to many. For people who've never built anything, it's overwhelming. To people who've only ever used gas or electricity, having a fire in their home may be terrifying, too complicated, dangerous, laborious... To people who have only used a typical fireplace for ambiance, during the holidays, it's messy. To people who absolutely love the entire concept of a rmh, and dearly want one - but are married to someone who falls into one of the previous categories (or any one of the who-knows-how-many other reasons I don't know to list), they may relent to the other person, instead of allowing it to be a wedge to drive into their relationship (this one is me). This is all not even including the practicalities of sourcing, building codes, insurance, etc.

Hurdles? We got 'em. But, so did the Wright brothers, and just look up at the sky, to find proof that their dream is now a reality. It can be done. It's worth it. It's important. There is a really crazy-smart guy that said something about trying something 1,000 ways, and maybe 3 working? Then, the other 997x must be part of the learning curve, right? How many ways has Paul/permies tried to get *this* ball rolling, so far? I'm not trying to be a smart-ass, I'm just trying to encourage P & team not to give up.

How are nuclear reactors talked about? As a source of cheap electricity that will be built by a team with lots of credentials, who will make certain it is 100%, cross our hearts will-never-poison-you safe. No trouble for the citizens, just don’t be a nimby and enjoy the cheap electrons. Articles about them are very professional and academic, giving the average Joe reassurance that these people can deliver on their guarantees. (Note: this is NOT a statement on how trustworthy these assurances are, just a comment on how it is marketed as a serious option).
How are Rocket Mass heaters marketed? With fun hand drawn graphics, by a bunch of diyers who clearly state they have no credentials in the field of civil engineering or fire safety, and make no legal guarantees that what you build with their plans will be safe. No engineer stamped plans, no warranties, just the information - and lots of videos of both working rmhs and catastrophic failures by random youtubers. (Again, NOT an opinion on the safety of rmh or on the expertise of those presenting it. Just a statement on how the information looks).
The average Joe is not going to feel equipped to read the information and decide for himself whether it will burn his house down or make his floor collapse, or whether it is as safe as advertised. He is not going to trust that what he reads and sees in videos is the whole story. And so, he is probably not going to share it with his friends - because he isn’t sure if its real.
Others have also said that the focus should be creating a path for professional builders and contractors to pull permits, run the numbers on engineer stamped plans, and feel comfortable putting  their names and reputations behind installing a rocket mass heater in the average home. Will the result be better than what an intelligent diyer who follows the instructions already out there can do? Probably not. But most people aren’t intelligent diyers who can follow all the directions. They need a “professional “, licensed bonded an insured person working on their home to feel comfortable with it.
Without that, I don’t see a magic bullet to deliver the info to more people. It would require a sea change in pur attitudes - to a willingness to spend a lot of time educating ourselves and trusting our own judgement and abilities - and the willingness of building inspectors and insurers to believe in us too.

I agree with the person who suggested templates for getting RMH into local codes. I think that's the first step to getting these in more people's homes. If I was a wood stove installer, I probably wouldn't risk my business by installing something that isn't allowed within the local code.

I think the core of this is that if the general public wanted rocket mass heaters, then all the other stuff would follow.  

So the first step is to get the most basic information to the general permies.


A guy once heated his home all winter with nothing but junk mail.


That was more than a decade ago.  I think the equivalent today would include amazon shipping boxes.

But is this the piece we need in order to get into millions of brains?

It seems like the core of this is to find a way to reach 100 million brains.  And, of course, I have no idea how to do that.  

Maybe the strategy is to do better with the materials I have on hand.  I cannot tell 100 million people, but I can tell 105,000 people.  Maybe there are a lot of the 105,000 people that could use a little more information.

Some of the suggestions in this thread are something like "hire a bunch of people to go do a thing".  Of course, none of us have that sort of coin.  But I suppose it is possible that somebody does - so it is worthwhile to make a list of those sorts of things.

My guess is that if 100 million people have interest, then all the other bits and bobs will show up to provide a service.  The first step is simply knowledge.

Here's the "beautiful rocket mass heaters" thread which includes some europe builds

https://permies.com/t/40573/beautiful-rocket-mass-heaters

My guess is that there are probably a few dozen more rocket mass heaters to be added to that thread.  But for now:

Maybe we need a massive rmh misinformation/excuse FAQ - so that all the little bits that block people from learning about rmh can be resolved.

I have barely started exploring the idea and I feel like I have access to plenty of information.   Facts are not the problem.

If we get more facts to more people, how does that further the dissemination, if facts are not the problem?

Charlie Tioli wrote:I have barely started exploring the idea and I feel like I have access to plenty of information.   Facts are not the problem.

If we get more facts to more people, how does that further the dissemination, if facts are not the problem?

I think ....


problem #1:   99% of people have never heard a peep about it



problem #2:   when people hear about it, they think something must be wrong with it, or else they would have already heard about it before now

Language matters.   I retired from a profession focused on language use (speech language pathologist).  If someone is gesturing and telling me something urgent, but I don't understand their language or it scares me, I won't try to discern that they're warning me or directing me.  I'll give up and walk away, perhaps to my own harm.  If I say something important in a way that it cannot be heard, I will try to find another way to say it.

I'm assuming the Rocket part of this heater name relates to the action of the combustion?

But because of the above language issue,  I'm going to further disrespect the "Rocket" part of the name:

A rocket requires a planet- sized mass behind it.   Will this heater blow out my back wall if I don't reinforce it?  Or will it shoot the wood across the room like a projectile?  Sounds silly/stupid to the initiated.   It's a reflex response to newly hearing the name.  "Blast" isn't much better. They both sound violent and dangerous.

I'm a gentle giant who prefers zero drama or danger.   I'll do something by hand to avoid using power tools.   So I'm going to offer unasked-for alternate names and invite anyone else who has ideas around this to join in.  I can already see enthusiasts squirming because all names are approximations (my whole point) and these names don't tell exactly what it is.   But then neither does rocket.   My idea is to alter the name in order to evoke a sense of safety, cozy warmth, and hearth.

How about:

1.  High Efficiency Fireplace
2.  Built in woodstove
3.  Zero emission burner
4.  Minimal fuel furnace

And my personal favorite:

5. Heat Hugul

Paul, I have so much appreciation for your awareness and concern, and much compassion for how painful it is to have an answer to a huge problem to which virtually know one will listen. The need for heat is going to really hit a lot more people this winter. It will be primarily the poor who suffer this cold; many will die from it. So how do we reach those poor folk and with a rmh or simply rocket stove (adequate for the truly poor) solution they can use?

I've had the experience of Trace and Aldo: lots of interest for quite some time, and a need, and willingness, but feel like I'm going down an rabbit hole each time I try to figure out how to buy or build what I need. Was going to buy even tho I really can't afford it because I was having trouble with plans that would work for me, but then the dsr and even the kits were sold out. Also, it seems like a lot of "rocket stoves" are not true rockets, and a lot are designed only for outside.  .... Even in this thread the first post for the Liberator lead to another permie thread instead of the product, and the link in that thread was for that same thread .... ARGH!!!

So, getting people aware is needed, but at the same time we need to have links for the 'woke' folks to find what they want: plans for various needs that are for real rocket heaters or stoves; links to rockets for sale and that aren't sold out and/or have waiting lists that have no dates for order fulfillment (I know this is problematic cause folks can't afford to build what so few people are buying: it's kinda a troublesome loop); how to get rocket heat without voiding home insurance (this may be the biggest issue for most home-owners given the limited availability of approved rocket heater/stoves). ...

Getting people interested probably requires being able to suggest 'products' they can buy or talk with the retailer about buying; at least in the USA that is the only road the vast majority know how to travel. So few people even change a washer in the sink: considering building even the simplest of rocket stoves is laughable for most people. Short of that we need readily available accessible plans: available materials assembled with limited skills.

I'm anxious to help in any way my skills and time allow. Let's do this.

Maybe what we need most is for somebody to start a new wiki here on permies that is "the ultimate rmh faq"?

Thank you Paul. That would be great for me I think. I don't know it'd be nearly as helpful to "the masses" as it'd likely go the way of ... donkey boards (? name): way to technical, too many tinkering questions to wade thru

Here's a promotional graphic to make it a bit easier for those of you wanting to spread the good word about rmh.  This infographic posts well on Facebook or other social media sites.

https://permies.com/t/190497/Promotional-Graphic-earn-fat-coin

paul wheaton wrote:Maybe we need a massive rmh misinformation/excuse FAQ - so that all the little bits that block people from learning about rmh can be resolved.

Sure, you can try. But I still think it comes down to credibility. Personally, I find you credible, even though we’ve never met, and I am not aware that you have formal training in engineering or other fields that teach you how yo design a stove. I believe that you have experimented and built enough that your info is good.
But if I want to share it, how do I communicate that? “There is this guy on the internet that says…” will my friends agree? Or will I lose credibility with them for promoting this crazy guy on the net who claims you can heat your whole house with junk mail?
I truly think this is a barrier to having things go viral. At this point, everyone knows you can’t trust everything you read on the internet. How is the rocket mass heater stuff credible to people who have only ever seen them online? And let me say - in general, I consider open forums less credible than an official looking informational page. Permies is an exception for me, but not my non permie friends. So threads will likely not be used as credible info.
I suggest that using the markers most people consider credible, such as engineer stamps, code guides, and warranties by professional installers, would be one way of making it seem like a serious, doable technology. There may be others. I have thought in the past that a “rocket mass heater builders association”, similar to the masonary stove association, might make them seem more “official”. Another possibility: get a description and build at a suburban home published in a credible periodical. I know Mother Earth News, Taproot, Grit - all of them will pay for well written and photographed articles. Mother earth, in an open search, has a single article about them, an FAQ. Grit has one article, Countryside has none. I don’t know what the readership of these are, but I think people assume that articles that appear there are vetted a bit more than an open forum or random web page.
Just my two sense. And speaking as someone who has yet to see a rocket mass heater heat a home in person.

My first idea is just to do a hard press on other forums and reach people where they're at. RMHs are conversationally adjacent to a ton of different topics, many of which have their own online discussion forums unique to countries that are currently experiencing energy crises of their own.  I just did some quick googling for variations on the phrase "france wood stove discussion forum" and "UK wood stove discussion forum" and "germany wood stove discussion forum" and got lots of hits:

https://arbtalk.co.uk/forums/forum/121-log-burning-stoves-and-fireplaces/
https://www.expatforum.com/threads/pellet-stoves.1512450/
https://forum.completefrance.com/index.php?/topic/33808-wood-burning-stoves/
https://www.toytowngermany.com/forum/topic/284958-using-a-wood-burning-stove/
https://www.yurtforum.com/forums/everything-else-f5/hello-from-austria-1444-2.html#post9701

Second idea: After watching a few episodes of the TV show "Nathan For You", my gut instinct tells me that you'd gain a lot of marketing mileage by hiring a busty actress in yoga pants and a skimpy top (or a ripped handsome shirtless dude with six-pack abs) to film a series of informational youtube videos on all the in and outs of RMHs. I've heard through previous discussions that the efficacy of this idea has been borne out by the view count on Paul's RMH video with the thumbnail of Erica Wisner's cleavage.

paul wheaton wrote:
And I just feel like right now is the time to get this information into a hundred million brains.  

But how?

Ive brought this up once before and even reached out to his website trying to get you or anyone else in the permaculture field on the show but so far haven’t gotten a response. But Joe Rogan can help you infect a hundred million more brains, if you can manage to get on the show. Here’s a quote:

“In January 2015, the podcast was listened to by more than 11 million people.[46] By October 2015, it had grown to acquire 16 million downloads a month.[3][47][48] In April 2019, Rogan said that the podcast had 190 million downloads each month.”

I think if someone wants to get information to the masses, he is the ticket. And he knows this, spotify knows this, his guests know this and his audience knows this. He would probably love to have an open conversation about this, but I could see there being quite a wait to get on if you can get a hold of him.

yurtforum.com ....    see

https://www.yurtforum.com/forums/building-a-yurt-f3/rocket-mass-heater-in-a-yurt-966-4.html

Beau Davidson brought up the idea of writing a pop song about RMHs. So I started a new thread with the goal of adapting the lyrics of a pop song. I chose "Hook" by Blues Traveler, but if there is a better tune we could go with that.

RMH Pop Song

I think one of the big reasons has already been mentioned in that most houses have conventional heating systems already installed and owners don't want the added expense or inconvenience of installing a RMH.
Here in Canada most insurance companies only insure EPA certified and WETT approved heaters, and don't insure homes with RMHs, because there is no EPA and WETT standard for them yet approved.
Once certification standards are set, I believe they are more likely to be adopted, but who knows how long that will be unless heating fuels go astronomically high like in Europe now. That might prompt governments to develop standards the insurance companies would honor.

paul wheaton wrote:Maybe what we need most is for somebody to start a new wiki here on permies that is "the ultimate rmh faq"?

A little wordy at the top, maybe, but here's a start:
https://permies.com/t/191801/Ultimate-RMH-FAQ

I'm a relatively new transplant from Florida to Nova Scotia, living in a conventional small town home.  We heat in the winter with a combination of a pellet stove and a heat pump.  Other local options are electric baseboard, oil furnace, and wood stoves.  I'd love to have a RMH.  Similar to what other folks have said, to make that happen I'd need to have someone local who could do (or at least inspect / certify) the install, and have buy-in from both city code and insurance that it was acceptable.  We have local licensed pellet and wood stove installers, but I'm not aware of anything like that for RMHs.

Building codes:  we've come a long ways.  Lots of codes now mention rocket mass heaters specifically.

Insurance:  the trouble with wood stoves is chimney fires.  So insurance companies love rmh.  

When it comes to rocket mass heaters and local codes, I strongly advocate that people do the exact same thing as was done with pot:  nobody touches it until the government says it is okay.  Even though it could save you thousands of dollars and/or is something that cuts your carbon footprint by 90%.

https://permies.com/t/38257/rocket-mass-heaters-local-codes

Beau Davidson wrote:

paul wheaton wrote:Maybe what we need most is for somebody to start a new wiki here on permies that is "the ultimate rmh faq"?

A little wordy at the top, maybe, but here's a start:
https://permies.com/t/191801/Ultimate-RMH-FAQ

There's a pretty good faq here https://richsoil.com/wood-heat.jsp

Maybe some copy and paste?

Abe Coley wrote:Second idea: After watching a few episodes of the TV show "Nathan For You", my gut instinct tells me that you'd gain a lot of marketing mileage by hiring a busty actress in yoga pants and a skimpy top (or a ripped handsome shirtless dude with six-pack abs) to film a series of informational youtube videos on all the in and outs of RMHs. I've heard through previous discussions that the efficacy of this idea has been borne out by the view count on Paul's RMH video with the thumbnail of Erica Wisner's cleavage.

There is also the less safe for work picture of the RMH in Cooper Cabin.

Maybe I can add a somewhat unique perspective...

I love this forum, you people are an amazing group, and I've come here for a ton of growing information.  That said, I'm a normie more than a permie and still have a lot of normal consumer habits.  I've known about RMH for years and while I think they're awesome, I would have a laundry list of questions, concerns, and emotions around them that would all need to be satisfied before I ever considered building one in my home.

Are they legal/code breaking?  Who would I get to install one?  If I attempted to DIY one, would it be considered illegal?  Is it safe/how certain could I be that if I did DIY one it wouldn't burn my house down (and it would have to be 10000% certain)?  Is it worth giving up precious square feet of my dwelling?  Can it be built in the basement?  Is the ease of maintenance there?  How does it work on larger, multistory homes?  Will it evenly disperse heat to all my rooms (if not, it's a no-go for me)?  

The average consumer fixes most problems by throwing money at a solution that makes sense and is convenient.  If there was a number I could dial right now that would get a reputable, insured craftsman here tomorrow to build an up-to-code, safe, well-made RMH at a reasonable cost, I would make that call right now.  If that isn't what's on the table, 95% of consumers are not even going to consider it.  

Just my .02

I had read on permies some years ago that rmhs can't hear large spaces, so that creates a large audience who would not benefit. When you talk about using scrap wood, there just is not enough energy for complete households.

Are there automatic feeders to keep the heat going? I looked into RMH, but settled for a heat pump using solar + storage.

Steven Gallo wrote:Maybe I can add a somewhat unique perspective...

I love this forum, you people are an amazing group, and I've come here for a ton of growing information.  That said, I'm a normie more than a permie and still have a lot of normal consumer habits.  I've known about RMH for years and while I think they're awesome, I would have a laundry list of questions, concerns, and emotions around them that would all need to be satisfied before I ever considered building one in my home.

Are they legal/code breaking?  Who would I get to install one?  If I attempted to DIY one, would it be considered illegal?  Is it safe/how certain could I be that if I did DIY one it wouldn't burn my house down (and it would have to be 10000% certain)?  Is it worth giving up precious square feet of my dwelling?  Can it be built in the basement?  Is the ease of maintenance there?  How does it work on larger, multistory homes?  Will it evenly disperse heat to all my rooms (if not, it's a no-go for me)?  

The average consumer fixes most problems by throwing money at a solution that makes sense and is convenient.  If there was a number I could dial right now that would get a reputable, insured craftsman here tomorrow to build an up-to-code, safe, well-made RMH at a reasonable cost, I would make that call right now.  If that isn't what's on the table, 95% of consumers are not even going to consider it.  

Just my .02

Good points for sure. Seems like nobody is bringing up the weight issue either. Its a lot easier to put a wood stove in basically anywhere you want as opposed to having to reinforce your floor first in order to support all the weight of a RMH. I even looked into conventional masonry heaters since I wouldn’t have time to build a RMH this year and the masonry heaters have a lot of the same issues: huge and heavy. If I were building a new house I would 100% plan for a RMH and take the time to do it well and enjoy the process. But when you’re just trying to have a stable heat source in the house you’re already living in, you’re working full time, money is tight and winter is approaching theres an awful lot to consider.

I still can’t figure out why my suggestion has gotten zero attention though. Maybe theres some political ideology working behind the scenes or something. But if the goal is to reach masses of people with free valuable information, I believe the JRE is the way to go. At least worth trying.

Steven Gallo wrote:Maybe I can add a somewhat unique perspective...
I love this forum, you people are an amazing group, and I've come here for a ton of growing information.  That said, I'm a normie more than a permie and still have a lot of normal consumer habits.  I've known about RMH for years and while I think they're awesome, I would have a laundry list of questions, concerns, and emotions around them that would all need to be satisfied before I ever considered building one in my home.

Are they legal/code breaking?  Who would I get to install one?  If I attempted to DIY one, would it be considered illegal?  Is it safe/how certain could I be that if I did DIY one it wouldn't burn my house down (and it would have to be 10000% certain)?  Is it worth giving up precious square feet of my dwelling?  Can it be built in the basement?  Is the ease of maintenance there?  How does it work on larger, multistory homes?  Will it evenly disperse heat to all my rooms (if not, it's a no-go for me)?  

The average consumer fixes most problems by throwing money at a solution that makes sense and is convenient.  If there was a number I could dial right now that would get a reputable, insured craftsman here tomorrow to build an up-to-code, safe, well-made RMH at a reasonable cost, I would make that call right now.  If that isn't what's on the table, 95% of consumers are not even going to consider it.  

Just my .02

Here's the "all-or-nothing" example, in plain sight. (thanks for this.)
Will it heat my WHOLE house? Maybe it doesn't... maybe your RMH only heats half your house effectively, maybe your existing systems continue to cover the upstairs, or distant rooms.
So, you retain your existing systems, just use it less. It's there if you need a break, take a vacation, or unseasonably cold weather sets in. Having a backup (and it works both ways) is a nice idea.

If it heats half your house, isn't your heating cost cut in half? your reliance on fossil fuels cut in half? Half seems like a BIG reduction.
It might even be better than half, since "downstairs" heated by RMH, warms "upstairs" some as well. It might also change your behavior in the cool seasons, to rely on the RMH rather than the thermostat, and be satisfied.

Floris from Batch Rocket Portugal built an RMH that has a burner and mass on the main floor, with a chimney that leads to a second mass directly above it on the second floor.

Floris' Instagram post

For those of you who are asking questions about legality and insurance and such. Are those questions holding you back from telling your friends about RMHs? If you got acceptable answers, would you tell your friends about them?

Jeremy VanGelder wrote:
For those of you who are asking questions about legality and insurance and such. Are those questions holding you back from telling your friends about RMHs? If you got acceptable answers, would you tell your friends about them?

For me, yes and yes.

Shooting from the hip here.. Folks who live in cold climates and have the know how are the best folks to bring this to the people.  I see a Rocket Heater booth at Christmas Fairs, Tool shows, Building industry conferences.. Someone with freedom to be a professional cheerleader,  by freedom I'm referring to someone retired from the daily grind with an income unconnected to rocket heating tech.  I  remember seeing a portable demo heater here on Permies.. we need MORE of those.. all over the country.
Second flash.. a team of permies elves build warm public benches in NYC.. BOSTON COMMONS, CHICAGO, SEATTLE, DETROIT, BUFFALO,  CLEAVLAND. In the cold cities, go to city hall meetings and ask to do a permanent public installations. Obviously it's imperative it be accompanied by a perfectly artful bronze plaque explaining the technology (the magical guts) a real blueprint in bronze. Imagine bus stations with RMH benches, cafés with comfy outdoor seating... etc
Getting RMH into public spaces is the key.
Another! Extremely high quality stencils of a RMH blueprint, large and legible. I'm suggesting guerrilla, information sharing, street art. I'd absolutely buy a well-made jumbo stencil.  I already buy them every few months for my artwork and jobs. The biggest ones sell for about 70 bucks. That would take someone who would want to figure out how to manufacture quality stencils, or finding a company who does custom work.  Screen printing is also good for some surfaces.  I have done screen printing on regular painted sheet rock with great results.  So let's say I have one of these.. I will go to a local Cafe and ask to do an art installation that teaches people about RMH, talk to science teachers at school,  health food stores, feed stores.. adding additional art with the blueprint would be fantastic,  that can also be a series of coordinating stencils. This sort of sharing would require a talented artist willing to create the base images for free.
A fundraiser in your local area could fund the public projects.. perhaps working with food bank volunteers could help connect with agencies that give aid to the elderly and other community members who care about promoting low cost solutions to help people maintain general health and well being.
I'd throw in my $25 bucks to a fundraiser to build more portable RMH to take to trade shows (and the likes) or any other permanent public installation someone might take on.
Cheers everyone,
Roxanne

Chuck Zinda wrote:I had read on permies some years ago that rmhs can't hear large spaces, so that creates a large audience who would not benefit. When you talk about using scrap wood, there just is not enough energy for complete households.

One rocket mass heater per 2000 square feet.  

They can do large spaces.  And really large spaces will have more than one rocket mass heater.

Are there automatic feeders to keep the heat going?

Usually they rely on the mass to keep the heat going.  But there are some, like the liberator, that work with pellets to do a constant feed.

I love them.  I want one.  I'm 100% sold on their efficiency, sustainability, cleanliness, etc.   I spent months watching youtube videos, reading about them,  following threads here.

I live in the city.   It's not legal.  I don't even care.   If I could stealth have a small one that was "invisible" to outsiders and could function as my alternative heat source without disconnecting from the grid and drawing attention, yup I'd do it.  

My concerns are more along the lines of ease of install,  ease of materials sourcing, repercussions if I DO get caught out with it,  and ease of removal if I decide to sell.   I haven't stayed in one home longer than 5 years in my entire 52 years of life.. so does it make sense?  I don't know.   It's a big project that never makes it to the top of the "can do" list.  

That's just me, one person, and my particular situation.   I can't answer for anyone else.  And I DO share info about them.. I tell friends, post on FB, share good youtube videos about it.