A rocket stove can be built four ways: a tin-can prototype in about 30 minutes, a brick-and-clay stove in 2 to 4 hours using 16 to 20 bricks, a cob stove that needs 3 to 5 days to dry, or a metal drum body. Whatever you choose, use only dry, already-fired materials and metal without galvanised or painted coatings.
Part of Rocket Stove Design
A rocket stove can be built from tin cans, brick and clay, cob or a steel drum. They differ in build time and durability, but all need dry, already-fired materials and an open exhaust path.
Pick By How Long It Must Last
| Build | Time (overview) | Lasts | Page |
|---|---|---|---|
| Tin can | about 30 minutes | Prototype | Tin Can Prototype |
| Brick and clay (16 to 20 bricks) | 2 to 4 hours | Durable | Brick & Clay Builds |
| Cob | 3 to 5 days drying | Permanent | Cob & Earthen Mass Stoves |
| Metal drum | not stated | Large | Metal Drum Variants |
All Four Share The Same Anatomy
A feed opening with a shelf, a burn tunnel, an insulated vertical riser and a place for the pot a little above the top. They differ in what holds the shape.
Materials To Avoid
- Damp or porous stone and concrete. Trapped moisture turns to steam on heating and can burst the material. Use dry, already-fired brick.
- Galvanised or painted metal. Heating can release zinc and coating fumes. Burn coatings off outdoors and stay upwind, or choose uncoated steel.
- Chemical drums. See the drum page.
Common Mistakes
- Building indoors without a way for the exhaust to leave. See Indoor Use & Ventilation.
- Skipping the insulation. See Insulated Burn Chamber.
- Firing a new cob stove hard on day one. Wet cob cracks.
Safety
Hot parts and bad fuel fumes
Bodies stay hot after the fire is out. Coated metal and treated wood give off toxic fumes. A badly built stove smokes, and smoke from incomplete burning carries carbon monoxide, which has no smell. See Carbon Monoxide Risks.
What’s Next
- Learn next: Tin Can Prototype — the quickest test of the principle
- Combine with: Rocket Stove — a separate treatment of the J-tube stove