Rocket Mass Heaters and the home owners dilemma (restrictions...)

My sincere apologies if I posted this when it's extensively covered. I've seen mention of this issue, but no solution.

Please tell me if simply there is no "solution" other than to do it anyhow?  I'm not sure if that's ever allowed to be advised here?

I live on a north facing slope on a mountain close to 8,000' elevation and I want a Rocket Mass Heater.  How have others addressed this with their home owners insurance?

My county will only approve of a solid fuel burning stove if you purchase the newest EPA stoves.  I want to be delicate talking to these people out of fear of getting shut down.  I spoke with people at Building Safety who handle this and their applications require the Make/Model/Manufacturer to be listed.  As I tried to explain you can build this the person said "surely someone has to manufacture the stove".  They don't get it.

I've contacted the people who make Liberator stoves and unfortunately they don't get the EPA rating because the EPA deducts from it's efficiency unless you pay a large sum to "prove" you're a big manufacturer to get it back.  

Do the owners of RMHs here simply build them without concern regarding their home owners insurance?  Does anyone have advice on how to handle this?

Hi S;
We would never suggest an illegal act like just doing it anyway... although that is exactly the choice some folks make.
We suggest asking your county about the masonry stove rules and regulations in your area.
A double-skin brick bell, batchbox IS a masonry stove.
I would not mention that I was going to be the builder.
Some states require that only a stove-certified mason construct a masonry stove.
This is the best way to approach getting official approval.

There is currently a poster in the RMH forum building his batchbox in Colorado, west of Denver at around 8000' perhaps you are neighbors!  

Thanks Thomas, those are some good suggestions.  When the person I spoke with sounded clueless about there not being a manufacturer for what I wanted to make, I indeed pivoted to saying "you know masonry stoves?".

He then said I was over his head and told me to contact someone else.  That's when I decided to check here for advice instead of saying something that might get my project flagged!

Do you remember which thread I can find that person who lives nearby?  I searched and only found this thread.  And looking on the RMH page there's so many I'm having trouble finding it.  Thanks!
(edit: If you mean this thread https://permies.com/t/238503/Batch-Rocket-Build , unfortunately that's far enough from Denver to get away with stuff like this.  But worth reaching out to)

Thomas is one of our experts though I would like to make a suggestion.

I feel the easiest way to get an insurance company to approve an RMH other than explaining that it is a masonry heater is to go with the Ul-approved Liberator.

Here are some threads:

https://permies.com/t/237541/Liberator-stove-installed-home-working

https://permies.com/t/208528/Free-Shipping-Liberator-Rocket-Heater

Indeed, S;    
That is the correct thread.  Glenn is building a very nice double skin batchbox at his home.
It would make a good example of a build you might be able to duplicate if you are allowed...

S. Marshall wrote:
I live on a north facing slope on a mountain close to 8,000' elevation and I want a Rocket Mass Heater.  How have others addressed this with their home owners insurance?

My county will only approve of a solid fuel burning stove if you purchase the newest EPA stoves.  I want to be delicate talking to these people out of fear of getting shut down.  I spoke with people at Building Safety who handle this and their applications require the Make/Model/Manufacturer to be listed.  As I tried to explain you can build this the person said "surely someone has to manufacture the stove".  They don't get it.

I've contacted the people who make Liberator stoves and unfortunately they don't get the EPA rating because the EPA deducts from it's efficiency unless you pay a large sum to "prove" you're a big manufacturer to get it back.  

Do the owners of RMHs here simply build them without concern regarding their home owners insurance?  Does anyone have advice on how to handle this?

I can feel your pain, Although it sounds like your being severely restricted on what you can do, I still like to suggest,(to others)  asking this question first.  What exactly does a wood stove (of any type) have to have to be wrong? or unacceptable?  In this case, they seem to be hung up on the EPA thing, And Peter V, of Donkey32 proboard fame, certainly has the numbers to back up the emission questions. I probably assumed wrong in that I thought UL was only for electric  items.We all know how politics works, if I had millions invested in MFG of an item, I would work very had to insure someone could not do it on there own. (thus regulations get helped by the MFG company to get put in place.  I know this still don't help.

But that being said, this house has burned wood for over 80 years, (coal too) and the batch box is by far the safest stove that has ever been here. I think I could show that to even the dimmest views of any inspector, but that doesn't help you. as you would have to have it done to show. (and still not know until your done) A dilemma for sure. I wish you the best.

Well, indoor woodfired pizza ovens are a thing some restaurants and rich people have.
It is unlikely that wood fired ovens are as clean burning as an epa compliant stove, and they are liable to custom made.
Regulations often have exceptions for things rich people want.

When a home builder wants to stray far from the conventional, regulations often call from an engineer to put their stamp of approval on it.
Usually this is very expensive 😕 but the right engineer might look upon a the extensive documentation on batch rockets and see the opportunity to become the goto guy for home built rocket mass heaters.
If there are any local certified pizza oven designers/builders, they might feel the same.

So yeah, maybe ask about installing a woodfired oven inside of a residential building and go from there.
A batch box rocket can include an oven in the bell, or the burn chamber itself can be used as an ove.

Anne Miller wrote:....
I feel the easiest way to get an insurance company to approve ... is to go with the Ul-approved Liberator.

Thanks Anne, except my county only allows newly purchased stoves to pass the EPA certification, something we all know it does, except according to Liberator they have to pay $50k in order to receive the actual rating. Unless you pay the $50k the EPA automatically chops off 16% of your rating (they subtract 16% from the tested HHV rating to account for the inherent variability of fuel sources in wood to "protect" the consumer).

thomas rubino wrote:Indeed, S;    
...double skin batchbox...

Scott Weinberg wrote:
...batch box...

Hi Thomas and Scott. I am only now learning about these varying types of Rocket Stoves (assuming Rocket Stoves are the engine portion of a RMH).  For the last 7+ years I always thought a Rocket Mass Heater was the 55-gallon barrel version with sticks as fuel sticking out of the feed chamber that are very ubiquitous here and on youtube.  I'm not sure why these other design types has eluded me.  Even terms like J-tube, Bell, and many more I somehow never noticed.  I've also been learning about WalkerStoves designs.  Is there a comprehensive guide that includes all these?  Do both of you feel like the batchbox is the best?

William Bronson wrote: ...Regulations often have exceptions for things rich people want....

When a home builder wants to stray far from the conventional, regulations often call from an engineer to put their stamp of approval on it.
Usually this is very expensive 😕 but the right engineer might look upon a the extensive documentation on batch rockets and see the opportunity to become the goto guy for home built rocket mass heaters.
If there are any local certified pizza oven designers/builders, they might feel the same.

So yeah, maybe ask about installing a woodfired oven inside of a residential building and go from there.
A batch box rocket can include an oven in the bell, or the burn chamber itself can be used as an ove.

I certainly appreciate this suggestion.  And I am definitely aware how this country works when it comes to money!

Scott Weinberg wrote:
...batch box...

.

Hi Thomas and Scott. I am only now learning about these varying types of Rocket Stoves (assuming Rocket Stoves are the engine portion of a RMH).  For the last 7+ years I always thought a Rocket Mass Heater was the 55-gallon barrel version with sticks as fuel sticking out of the feed chamber that are very ubiquitous here and on youtube.  I'm not sure why these other design types has eluded me.  Even terms like J-tube, Bell, and many more I somehow never noticed.  I've also been learning about WalkerStoves designs.  Is there a comprehensive guide that includes all these?  Do both of you feel like the batchbox is the best?

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scott weinberg says-

Well I will take a stab at this. but many may be able to put it into words better.

on the batch box, (mine) I can almost set a clock to when I start it up, within minutes it is running and in two hours I am down to a small bed of coals. At which point if it is really cold, I can add one more batch, which is almost instant combustion because of the super warm fire box  Or I just close it down for an evening burn.  At no point is the ROOM or surrounding area super hot.  But hours later it is still warm long after the 2 hour burn.

I can hold far more wood in this batch so no feeding it  (some call this more power per attention)

While you certainly can do a batch with nothing but barrels, I can't imagine how hot the room would with on my stove.

The sizing work is very well established for what ever size you decide to go with.

Now for safety=  Even when my batch fire is nearing 2000 F, you could hold your fingers 2" from the air inlet and not burn them- The air is rushing in and going away from the door.  Thus, if your door somehow opened up, at least on mine, zero would come out into the room all the way to the end.

You could have your bell very close to the wall, and your not going to be lashing 600 degrees or more at the wall

Although true on a J,  The bell really gives you a area of facade treatment.  Hopefully you will see in the photos,  This was a test bed for granite/tile and brick  All work well.

Lastly and I hope I can show it, you can have a nice size window on the batch door if desired and is certainly as please to look at as any inefficient fire place door. ;-)

Scott Weinberg wrote:
...While you certainly can do a batch with nothing but barrels, I can't imagine how hot the room would with on my stove....  
The sizing work is very well established for what ever size you decide to go with.....
....You could have your bell very close to the wall, and your not going to be lashing 600 degrees or more at the wall...
.....Although true on a J,  The bell really gives you a area of facade treatment.  Hopefully you will see in the photos,  This was a test bed for granite/tile and brick  All work well.

Thanks Scott! Now I remember reading about the batchbox, this makes sense.
For your first sentence I quoted, did you mean because the barrel is steel it could possibly overheat the room?  Whereas the brick bell version is brick or similar and therefore just warms up?  So in a sense, the non-barrel version has more thermal mass because the bell is made of brick?  Also, would the barrel be considered a bell as well?

That would explain why you say you can put it closer to a wall I assume.  Thanks!

S. Marshall wrote:

Scott Weinberg wrote:
...While you certainly can do a batch with nothing but barrels, I can't imagine how hot the room would with on my stove....  
The sizing work is very well established for what ever size you decide to go with.....
....You could have your bell very close to the wall, and your not going to be lashing 600 degrees or more at the wall...
.....Although true on a J,  The bell really gives you a area of facade treatment.  Hopefully you will see in the photos,  This was a test bed for granite/tile and brick  All work well.

Thanks Scott! Now I remember reading about the batchbox, this makes sense.
For your first sentence I quoted, did you mean because the barrel is steel it could possibly overheat the room?  Whereas the brick bell version is brick or similar and therefore just warms up?  So in a sense, the non-barrel version has more thermal mass because the bell is made of brick?  Also, would the barrel be considered a bell as well?

That would explain why you say you can put it closer to a wall I assume.  Thanks!

I re-read what I wrote, and will try to make it a bit better worded.

What I was meaning was:  if you made  a rather large rocket stove, (8-9 or 10")  with only barrels to radiate the heat from the fire box, Your going to have tremendous heat for a short time, but without mass, no real storage of heat.  They certainly have there place though.  But in my case, it would do no good, to have the center part of the house 120 degrees.

With a brick bell (MASS) and sized correctly , you should be able to get the bell up to temp, with the flue temps staying in the 150 to 175 range. This type of heat for home living, has proved to work very well, with constant release of stored heat, again this is a product of the MASS -- so  in very simplistic terms, -- 1 pound raised 1 degree equals 1 btu-- This of course has some efficiency variables but for our needs, the formula works well

So to get to your Barrel question vs warming the room...   yes to the barrel, if you want instant heat to really warm your area for a shorter time.  Plus having this barrel really close to walls, needs some precautions.  Where a Brick Bell, could be very close to the wall, with not to many worries (under 300 degrees)

I am not the right person, for the terminology on barrels being called bells, but someone will jump in.

I actually just checked with my insurance company today to ask them if it was a problem to replace my existing old wood stove with a “masonry style heater” and they told me it is fine as long as it was not my primary source of heat… BUT with the (rather significant) limitation of it has to be built by a certified installer.

Arliss Wirtanen wrote:I actually just checked with my insurance company today to ask them if it was a problem to replace my existing old wood stove with a “masonry style heater” and they told me it is fine as long as it was not my primary source of heat… BUT with the (rather significant) limitation of it has to be built by a certified installer.

How do you find and who certifies an installer?

Certified in Heating  and cooling (furnace-HVAC) or certified in Masonry?

I would want to know more, And then of course, what constitutes as primary heat source.  (in this case, something that would heat the house, if you could afford to run it?) Or something you actually have to use?

Those are tuff questions, but it sounds like, you will need to know.