In today’s culture of environmentally friendly and resourceful living, the art of cob building has been revived. Around since prehistoric times, cob is not only all natural but also inexpensive, reliable, and energy efficient. Today’s market in the United States finds this to be a perfect building alternative desired for its form, function, and cost.
Cob is a building material consisting of clay, sand, straw, water, and earth. It is fireproof, resistant to seismic activity, non-toxic, and creates no waste. In addition, it won’t burn, bugs will not eat it, it requires minimal tools to construct and as mentioned, is energy efficient.
Cob is a mouldable material that can be sculpted with your hands, lived in, and passed down through generations.
It is also found across the globe and in a variety of climates. Today, it is found that there are cob homes still standing after 500 years.
The technique of cob building has remained simple throughout the years, relying on only small changes such as using a tractor to mix the ingredients instead of your feet or that of an Ox. To begin, the ingredients are mixed then ladled onto a stone foundation in courses and trodded by workers in a process known as cobbing. Once the finished courses are dry, workers would trim the walls and then begin the next course leaving lintels for later openings such as windows and doors. The time it would take to complete a project would depend on size, complexity and the rate that each course dries.
On average the walls are generally 24 inches thick with corresponding deep windows. This thickness provides an excellent thermal mass that allows for warmth in the winter and a cool in the summer.
In addition, the material has a long life span even within rainy climates. This is of course due to the walls being protected by a large roof overhang and a tall foundation. It is found that the oldest structures are also finished using a type of stucco; protecting the walls further from the climate.
As you can see in the video provided below, a cob home is extremely unique having no two the exact same. This uniqueness can create difficulties if needing financing, building permits, or when needing to resell. However, for those looking for an inexpensive, Green home, cob building can provide you with what you are looking for.