a beautiful rocket mass heater build on youtube

When making the first rocket mass heater 4-DVD set, I thought "this is like bigfoot footage. Eventually, somebody will do a far better job and these DVDs will become redundant."

This is the far better job.  I'm not sure all the rocket mass heater stuff we sell is entirely redundant, but the value of it is dramatically diminished by this video existing.  A good build, that is well explained.  It is movie quality, but free on youtube!

Another wait for me, unfortunately. I submitted plans for a Walker rocket cookstove (a combination semi-mass heater and cookstove) to our local building inspector, and he said no. Doesn't have any basis for assuring that it is safe. He added that he would need an architect or engineer to approve the plans if he were to accept it.

Anyone know an architect or engineer who is familiar enough with rocket stoves to put her or his name on a plan submittal? In Michigan would be the easiest.

TIA

Hey Jerry;
What are the rules about masonry stoves in Michigan?
A batchbox with a bell is a modern version of a European masonry stove...
In some states, you need a certified stove builder and in others, you just follow the guidelines supplied.

thomas rubino wrote:Hey Jerry;
What are the rules about masonry stoves in Michigan?
A batchbox with a bell is a modern version of a European masonry stove...

I will check, thanks.

Chris McClellan (Uncle Mud) has experience explaining RMH to code officials so they understand how it is safe and fights into code.

Jerry McIntire wrote:Another wait for me, unfortunately. I submitted plans for a Walker rocket cookstove to our local building inspector, and he said no… in Michigan.

Also in Michigan here. Inspector’s are not knowledgeable about anything other than regulations. None of them build anything. You can either hire an engineer now or ask for forgiveness later. Those are your options.  Homeowner regulations are way more reasonable than commercial regulations, but incompetence is still horribly rampant in all Michigan agencies, and it’s spreading to the UP fast. The “permit” is the enemy of competence, and a friend to the incompetent.

There is a missing part to these calculations. Yes the rocket stove will produce heat efficiently but it is still going to go up to the ceiling. The important thing is the heat at the floor level because having cold feet is the worst and people are often sitting down indoors. Warmth  at the ceiling level is no good. Such a stove is going to pull a pile of cold air into the house. Fresh air is good but chilling the floor isn't. Heating this intake air is the trick to getting rid of the cold air at floor level. You could put another pipe to bring the intake air thru the bench. You could also use these principles to bring it thru a solar collector and use thermal mass of the ground to take the chill out first. I did something like this and it worked pretty well. Having a fire during the warm part of the day would increase efficiency since your intake air is warmer at that time where as people usually burn a fire when it is cold at night. You could still do it but it is less efficient. With solar preheating the air  you could burn a fire during the day really efficiently but it might not be necessary. The steady flow of warmed air it produces could have already heated the house enough during the autumn that it can hold up over the worst of the winter and recover quick in the spring. It was a great set up. The intake air would tick upwards in temperature as soon as it started getting light and then the sun would hit the collector. With the strain taken off the pipe the thermal mass can recover temperature to the pipe and start charging back up. I think it is a better use of time to set something like this up. If you have a designated intake it is going to raise the pressure inside and less air is going to leak in thru colder ways. Air quality is the main thing to take care of.  A metal pipe inside a mass collector seems like it would be good air quality. Maybe better than the usual air vents eg. plastic pipes. You could use a normal stove and it would still work much better with the preheated intake.

Turns out that Michigan uses a slightly amended version of the 2015 IRC (International Residence Code), which has a section for masonry heaters that are site-built. I am sharing that information with my building inspector...

During our recent build I had a subscription to the Green Building Advisor. Some of those guys are engineers, some of them helped write state codes. They're a knowledgable bunch. Amongst the other things I learned, one point stands out: Codes were put in place to ensure minimum standards, but have morphed into the standard to attain, inadvertently dumbing down the whole industry.  Related to that is that there are few knowledgable/build-intelligent building contractors anymore, and bascially no build-intelligent inspectors. (I can't think of a better way to say that.) Consequently creative, quiet non-compliance seems to be the intelligent recourse for those who are forward thinking and/or unwilling to settle for less than best. (Creative being the key word here.)  

It took us 2 years to start our build.  We couldn't seem to get our head around it.  Then someone in this forum replied to someone else with a link to this video and it finally clicked.  

My husband watched the video.  I took screenshot and so our RMH was born.  

Video is a dry run and we aren't quite there yet.  We also tried to follow the Pebble Mass RMH.

Jenny it looks like your burn tunnel is only 4” high?

Fox, I think the lower course of firebricks (the offset ones) are part of the vertical face on the inside.

Jerry, if your inspector is amenable to conversation you can converse about masonry heater code allowing for a builder (not engineer) familiar with that particular masonry heater design to build the rocket heater to ASTM or ANSI standards.

Thanks again to everyone who had replied. I had a good conversation with the county building inspector on Friday. He asked to see the ASTM specifications for a masonry heater. He understands that I want to build the rocket cookstove myself, following the Walker plans. I will be sending him the ASTM standard tomorrow.

I've noticed the author here uses a few techniques that seem a bit different from what I assumed the permies.com conventions were. For one, using female duct covers over male cleanouts, is this how they have been done at Wheaton Labs?

How about his recipe for repair/sealant mortar? Not sure why he seems obsessed over the red/white/purple/whatever shading of the clay, but is there more or less a standard around here on what to use for that application, particularly to avoid the cracking he experienced with the earlier mixture?

paul wheaton wrote:This is the far better job.  I'm not sure all the rocket mass heater stuff we sell is entirely redundant, but the value of it is dramatically diminished by this video existing.  A good build, that is well explained.  It is movie quality, but free on youtube!

Movie quality, but I'm not sure the information given was quite as good as it could or even should have been. Don't get me wrong - great that someone built a REAL rocket mass heater (for a change) and made a comprehensive youtube video documentary of the process, theory, thinking, etc. I just feel like this was a "rich man's toy heater" build focused more on making sure the wifey didn't make him sleep in his $250 dog house. I'd be happier with a "heat my home without spending a friggin fortune" build. The heater came out looking nice and definitely was done well for a first build, but all those spanking new parts and pieces, the overly-attentive detail and finishing work, etc left me shaking my head a lot.

I'm definitely biased with a "make do" and "if it works, who cares what it looks like" attitude, but the video left me wanting. Big time.

AKA, Paul's DVDs are almost certainly still worth it (though I've never seen them because I don't have money to spend on things I want)

Permies friends, I just found this video of a Korean man building a house. It is amazing to watch his artisan skills. From woodworking to a type of rocket mass heater. It is something to see and consider the possibilities. There are several videos in the series showing various aspects of building.  So brilliant and inspiring.  https://www.youtube.com/watch?v=bdxzTMrbedg