This document provides step-by-step photos detailing the construction of a rocket mass heater. It shows preparing the area with a moisture barrier and gravel base. Bricks are then laid in concrete to form the combustion unit structure and heat flues. The barrel support and bridge directing gases to the pipes are constructed. Insulation and a test run are completed before sculpting the finished bench. The document aims to inspire others to build rocket stoves and provides contact information for workshops or assistance.

1. Detailed pictures of the construction
of a rocket mass heater
By josh , rocket mass heater at Organizmo, colombia
Not me in picture and not at Organizmo.
It is another rocket project in colombia that i am invovled in though ;-)

2. Preparing the area
First there is of plastic (pvc or similar) as a moister barrier. After that a layer of gravel a
laid fairly level. On top of the gravel i poured a thin layer of watery concrete with gravel on
top of everything and maintaining the level. Big rocks are layed on the border with concrete
to hold them in place.
This is all done to protect the cob and stove from moister from below and also raising It a
bit off the ground.

3. Laying a base for the bench
A course of bricks in concrete because
bricks is what i had, could be anything
sturdy enough,It is just to raise the bench
from the ground.

4. Laying out the flues these are ceramic pipes
Most common here is smoke ducts, they are
usually quite coslty and these were a good
dimension a about 8 inches.
These pipes determined the dimensions for the
rest of the stove.
Since there are no connections for these pipes i used
scraps of metal and chicken mesh covered in
cement/cob mortar. (no- straw cob)

5. Construction of the combustion
unit

6. Used in total
about 50 bricks

7. base layer
first course of bricks : make sure it is wide enough for the courses of
bricks and for the bricks that will hold the a barrel which you will see
soon. the hole you see is a ash pit.

8. Layer 1
these bricks are layed flat, this layer will determin
the length of the burntunnel. Need to measure this
before hand beacuase the bricks can be different.

9. Layer 2
This layer the bricks are stacked on
edge, around the entire layer beneath.

10. Layer 3
On this level i had to cut off one third of two
bricks to maker It work. Now it is ready for the
heat riser!

11. Creating barrel support and the
"bridge" to the pipes.
Creating the support for the barrel and
directing the gases to the pipes. I find
it easiest and strongest to do with
bricks. It can be done with rock ,cob, or
a combination of everything.
Can you see what is wrong with the picture above? No? Well the bricks should be
locked together like puzzle pieces. Ana-maria from organizmo reminded me! Bricks
stacked straight on eachother will flop over.

12. Now the bricks are stacked
properly and mortared
together with sand/clay.
You can see the bridge to
the pipes being created.the
Hole there is going to be the
cleanout.

13. The bricks are plastered in and out, smoothed
out And the bridge is made wire mesh and
cobbed up.
Heatriser and insulation in place!
This inuslation method is not
reccomended and is experimental. The
heatriser is ceramic tubing, the
insulation is a charcoal mix with wet
clay and put In a chicken wire
cylinder. Other tested insulation
methods are advised. It is what was

14. In-between hobbies include, Burning off paint from the
barrel, mixing tons of cob (literally) and tincering with mini rocket
experiments.

15. Test drive
Putting up the barrel and giving her a test run! This gives you a final chance
make adjustments like: putting the barrel at the desired height or the height
which gives the best draft. Ok it works! Now what?

16. Sculpt a bench!
Ready for plaster!

17. Plasters
After testing a few batches here is the best i came
up with:
plaster for top half
1 part clay
2 part sand
1 1/2 cow manure
1 part flour paste
A few handfuls
plant fiber ( fique)

18. Platster for bottom half
1 part clay
2 parts clay
1 part clay soil
1 part rice husks

19. ready to go!

21. This slide is ment to assist you if you are thinking of creating a rocket stove, or just as
inspiration. It is not a detailed description it merely shows the main steps through pictures.
If you search the web for rocket mass heater you will find the dimensions you need for
your stove. I highly reccomend reading the book about rocket mass heaters.
Alright! Hope you are making one right now! If not and you want to, send me an email
and i can hopefully help you out!
I am willing to come hold a rocket mass heater workshop with you as well!
Thank you all at Organizmo for the help and support with the creation of this stove!
http://organizmo.org/
Joshua Roxendal
joshua@roxendal.com
Http://pemakultur.ihop.nu