The Rocket Mass Heater Builderвђ™s Guide: Complet... 🎁 Top

Guidance on using earthen materials like cob or masonry to create functional seating that acts as the primary heat sink.

Instructions for assembling the feed system, burn tunnel, and riser with heat-tolerant refractory materials.

by Erica and Ernie Wisner is a technical manual for constructing ultra-efficient earthen masonry heating systems. These systems can heat a home using 70–90% less wood than a traditional woodstove by capturing exhaust heat in a thermal mass, such as a cob bench, which radiates warmth for 12–24 hours after the fire is out. Core Principles & Design The Rocket Mass Heater Builder’s Guide: Complet...

Hot exhaust gases are routed through long horizontal channels (often inside a bench) that absorb and store heat instead of letting it escape up the chimney.

The book provides detailed, step-by-step instructions across several phases: Guidance on using earthen materials like cob or

The guide emphasizes the heater as an integrated system rather than just a stove. Its performance relies on a "rocket" combustion core that achieves complete, smoke-free burning through:

Covers site selection, floor load requirements (the mass is heavy), and navigating local building codes and insurance. These systems can heat a home using 70–90%

The system relies on a strong internal draft created by the temperature difference between the hot riser and the cooling exhaust in the mass. Key Building Sections