Cob is nontoxic and completely recyclable, which is important in this era of environmental degradation, dwindling natural resources and chemical contaminants. Cob is one of many methods for building with raw earth, the world's commonest construction material. It surpasses related techniques such as adobe, rammed earth pise, and compressed earth bricks both in ease of construction and freedom of design. Building with cob is a sensory and aesthetic experience like sculpting with clay. You can add on, cut out, or reshape at any time, even after the cob is dry.
Cob is a recent arrival in the United States.
Except for adobe in the Southwest, earthen building is virtually unknown here. In other parts of the world, cob and similar techniques have been popular for millennia. Throughout Western Europe, many of the picturesque stuccoed or whitewashed buildings are actually made of cob. In England there are tens of thousands of comfortable cob homes, many of which have been continuously inhabited for over 500 years. The durability and comfort of these valuable houses has sparked a renaissance in traditional cob centers such as Devon, where cob homes are again being built.