Hello! We are a group of Purdue University students studying Construction Engineering and Management. This semester our senior design group is looking to build a rocket mass heater following The Rocket Mass Heater Builders Guide and post progress photos along the way, similar to Eric Hammond's RMH Project. Our purpose in building the initial RMH is to eventually apply what we learned to designing a larger custom RMH. The first RMH will be used to heat a 25' x19' greenhouse in northern Indiana. The larger RMH will include a curved bench for a talking circle at the focal point of a community center (~1500sqft) in South Dakota, while also serving as the space's sole heat source. We are currently creating a list of materials to get a estimate budget for the first build. We've been given ~$500 to spend, but may be able to secure additional funding. Any cost saving suggestions are greatly appreciated. We are currently trying to find local/Indiana supplier of full-sized fire bricks. It appears that hardware stores carry the half bricks, but not the full-size. Is anyone aware of a store in Indiana that would carry full-sized firebricks? Thanks!

Hey Bradley:  Welcome to Permies!  Excellent projects to work on !

You need to locate a Masonry supply house. I promise that there is one in Indiana.  They will have full firebrick , half firebrick , 50# sacks of fireclay and builders sand all in one location. You just need to find them. If you can't locate one then switch gears and locate a mason, call him up and ask where the nearest supply house is located, He will know.

EDIT)   http://www.curleybrick.com/       Westfield , Ind.   should have what you need.

You should be able to find a used barrel for free or at most $20, just be sure the previous contents aren't hazardous when burned. You can use totally recycled red brick as well, and for the insulation get a big 20 pound bag of perlite and mix it with minimal clay slip to make the insulated heat riser and fire box areas. Used ducting works too for the bench, just a matter of scrounging and making sure the proper cross sectional area is used throughout. Check Craigslist too, that's how I found the barrels and bricks I bought for mine. You can probably just get a bale or two of straw and mix it with the local soil for the cob.

There are many of us here that enjoy the build ourselves, but when we are not involved in a project of our own, either helping or just peeking over the shoulder of another's build is satisfying as well in a different way.
The art of scrounging or Magyvering with what you have is how the rocket mass heater revolution really first began so don't feel like you need to buy all shiny new stuff because you know what?.... Most of it is going to end up being covered in mud!
Safety and longevity of materials are usually the only things that you need to keep in mind for what you can use in your stove that meets your skill sets and comfort levels.
Look forward to seeing your builds progress. Take pictures like Eric did.... we all like them!