This masonry heater was built in Southern Argentina in a 500 sq ft cabin that serves as a dormitory for students and teachers at a school dedicated to teaching natural building and permaculture design. Even though the space is small, the clients were intent on having a heated bed and wanted a heater that would be very responsive, given that the local climate is extremely variable, with freezing nights possible in summer and warmer days possible in winter. A further criteria was that the stove be built economically to demonstrate that efficient masonry heaters need not break the bank. The stove was built with these criteria in mind and accommodating the materials and space available.
This masonry heater was built almost entirely with common red clay bricks laid in clay-sand mortar hand mixed on site. Because it was built in a climate where winter temperatures are mild and variable, it was built as a “single-skin heater,” which means that there is only one brick between the path of flue gases and the room. The result is a heater that gives off heat instantly via the cooktop and door, but also stores heat and releases it slowly during a period of 8-12 hours after one full load, which takes about 1.5 hours to burn down. (In North America, masonry heaters must have an inner lining of refractory bricks and an outer lining of additional masonry material. This makes them more gas tight and with lower surface temperatures but also makes them less responsive and thus less apt for variable climates.)
The design was inspired by and is a hybrid of rocket mass heaters, the Gymse, bell heaters, and the work of many North american and European masons. Flue gases heat the entire mass of the stove, including the bed/bench. During firing the cooktop is hot enough to boil a kettle of water.
The project was a collaboration between Jon Santiago and Jeremiah Church as well as the crew of BioConstruyendo Patagonia.
With Pastor Silvestre, owner of the property and one of the founders of BioConstruyendo Patagonia, a teaching collective of natural builders.