William Bronson wrote: Building with what's on hand will keep financial risk at bay.
If I build a failed heater instead of watching TV, wasted labor won't be an issue either.
He's dead Jim. Grab his tricorder. I'll get his wallet and this tiny ad:Rocket mass heaters in greenhouses can be tricky - these plans make them easy: Wet Tolerant Rocket Mass Heater in a Greenhouse Plans