The charring process, in which planks were stood on end around a small brick furnace, helps to inoculate the wood against pests, fungus, and rot.

Bogie hearth resistance furnace bearing and susceptible to collision parts with high strength refractory brick masonry, and the use of water glass during building the mud, so the strength increase.

It is important to insulate the furnace from any neighbouring woodwork with brick and asbestos.