Building the perfect prepper retreat or creating a home for your family to live in with survival in mind can seem like a daunting task. Many factors go into making such a monumental and costly decision. The location of the home, annual weather obstacles, fire preparedness, and the ability to withstand an armed attack are just of few of the items to take into consideration during the initial phases of the home building process.
There are many viable types of economical and off-grid home styles to choose from. In my first book, Power Grid Down: Prepare, Survive & Thrive After The Lights Go Out, I go into great detail on this topic. One of perhaps the most economic and weather-resistant types of dwellings are cob homes.
What Are Cob Homes?
Cob homes are clay-based structures composed primarily of soil, straw, and pine needles. This style of building gets its name from the Old English term for “lump,” referencing the lumps of clay soil used to mold the earthen walls.
Cob homes were once thought of as just temporary housing structures, but many of the dwellings, which are constructed primarily of items found in nature, have been known to last for more than 100 years. Even if you are not currently planning to build a new survival home or prepper retreat on your property, cob buildings could still be a valuable addition to your land.
Cob structures could quickly and economically be constructed to house livestock, grow plants, or be used as an LPOP (lookout post – observation post). They could also be used as additional housing for loved ones and mutual assistance group members during a disaster.
Before there was a Lowe’s or Home Depot in almost every county in the United States, early pioneers built their homes from whatever materials were available and affordable. You can’t really get any more “readily available” or “cheap” than the dirt beneath your feet.
Cob homes first began appearing in what is now America during the early 1700s. Immigrants from Europe were well-versed in the benefits of building cob homes and continued the practice after relocating here. Some cob structures in the United Kingdom have been standing for more than 500 years. In Yemen, a 9-story cob home has stood the test of time for more than 700 years.
The building process for cob homes does not require construction expertise, nor will you need heavy equipment or a host of power tools. A small cob home could be completed for about $7,000 in most areas. The wonderful Appalachian county where I live does not have any zoning or a building code office. I could decide to build a 50-foot purple fence around my home with my own hands if I wanted to, and no one can stop me. However, not everyone is quite so lucky. Before digging up the clay soil to start building an economical and attractive cob home, make sure you are keenly aware of all the government hoops you may have to jump through to construct your own home from non-traditional materials.
Cob Home Attributes
Although the thermal capabilities of cob homes vary by region, the structures have long been known to absorb large amounts of heat and retain the warmth when low to moderate amounts of wood are used in the fire place or woodstove to heat the home Building a cob house in the northeastern region of the United States will not provide the same amount of insulation benefits as a similar home constructed in the southwest. Boosting the insulating materials used on interior walls will help solve the heat retention issue. Mix more straw into the cob mixture to boost the heat retention in the home. Cob walls are typically built between one and two feet thick to provide proper insulation and to allow for passive solar heat. They stay cool in the summer and retain their heat in the winter.
Cob Home Strength
Cob homes have also been known to withstand earthquakes and hurricanes. Such dwellings were once common in the area that is now known as Florida. If a home is damaged, the damage can be quickly and easily repaired by mixing up some more cob material and patching the cracks or holes.
While it would be foolish to call any type of building method “earthquake proof,” multiple cob structures have withstood seismic activity when other dwellings around them were significantly damaged or collapsed. The Cob Cottage Company in Oregon, a group that builds structures using the cob method and teaches others how to do the same, revealed that a portion of both the Great Wall of China and the Pyramids were made using the same earth-construction method. The company also noted that a luxurious mansion in New Zealand survived not one, but two massive earthquakes without experiencing a single crack as the rest of the town was utterly destroyed.
Cob homes are built in a monolithic manner, reinforced by straw and pine needles. This method of construction negates the weaknesses created when straight-line mortar joints are used in traditional home-building methods. The earthen building process used in cobs lends itself to curved structures, also a plus in the structure department. A cured or arced structure absorbs and more evenly distributes the impact of storm winds, rain, and flying debris that a structure built with narrower pressure points and joints.
Cob Structures vs. Rain
Like adobe homes, cob is very resistant to weathering caused by rain and snow. However, as happens with papercrete and straw bale homes, moisture can become an issue. Although a cob house can survive many heavy rains—even tropical torrential downpours—without weakening, it is highly advisable to create sturdy and wide eaves on the roof to protect the walls and foundation from constant pounding.
Fire And Air
Cob homes are extremely fire resistant and can easily accommodate a woodstove or large rocket barrel stove without fear of flames, but of course, proper ventilation is required, as in all homes. If the cob home is not going to be an off-the-grid dwelling, electrical outlets can be incorporated into the structure, just as they can be added to papercrete, straw, or adobe homes.
You could set up an air conditioning unit inside the earthen homes, but unless you are particularly sensitive to the heat, it is unlikely that one will be necessary.
[Image via Derek Harper/Wikimedia Commons]