Rammed earth is a construction technique used in the early days for creating firmand durable walls or floors.

The technique was also utilized in the construction of the wood-fired kiln at ZhunanSnake Kiln. The snake kiln built by founder Lin Tien-Fu in 1972 is lined by suchrobust rammed earth walls on its two sides. When building the kiln walls, half-wet,half-dry earth is loosened and poured between the inner and outer walls. A claylayer of at most 10 cm thick is poured in at a time, then tamped with a woodenhammer. At first a pressing force is applied to force the air out of the clay. As theearth slowly becomes more compact, the tamping force is gradually increased untilthe clay is solid and no longer depresses with each strike. In this manner, the earthis tamped, layer by layer, until the desired height is reached. The rammed earthlayer can be seen as an enormous, solid brick.

Using rammed earth layers to expand the kiln walls can add thermal insulation while improving the durability and sturdiness of the entire kiln, preventingdeformation. It also prevents the kiln operator from sweating profusely due to theheat of the kiln during firing. The rammed earth layers give the kiln excellentinsulation, allowing the inside temperature to be raised rapidly. This is one of thesecrets that allow Zhunan Snake Kiln to fire at such high temperatures. In addition,the pressure inside the kiln can be conducted underground through the rammedearth, making the kiln safer and more stable.