Cob House

FAQ:

Q: What exactly is Cob?

A: Cob describes a technique using earth mixed with straw and sand to form hand-built structures. The ingredients make cob incredibly inexpensive to use as a building material. When it dries, it's hardness is similar to concrete, and so can be used for load bearing or self supporting walls. Despite initial impressions to the contrary, cob has been successfully been used in all varieties of climates, including rainy and snowy environments.

Q: Is it exactly like Adobe?

A: Cob is a similar method to Adobe or rammed earth, but is more flexible and can be used to form more complex shapes such as arches and curved walls. It is also more likely to be built in colder and damper climates, where as adobe is typically restricted to a dryer atmosphere.

Q: Why aren't there more Cob homes?

A: Cob building has only recently caught on in the United States, though Western Europe has a wide variety of cob homes, many of which have been around for some time (hundreds of years). The proven durability of the style has led to a much wider interest in the process, and many new cob homes are being built each year.

Q:Is it really waterproof? It's made of dirt!

A:Surprisingly cob is quite resistant to weathering due to it's porous nature. This allows it to withstand long periods of rain without weakening. To provide mroe security to the foundation, many builders use a "boots and cap" strategy. This utilizes a wide roof to protect the walls from too much moisture.

Q:Doesn't it get cold and wet when it rains?

A:While insulation is typically less effective in a cob home, the large amount of thermal mass it provides means that once the building is warmed up it tends to stay warm. They are exraordinarily well suited to passive solar construction.

Q:Does it take a long time to build?

A:How fast you can build a cob house depends entirely on how many people you have available. While a typical house needs all sorts of spackling, sanding, and painting, a cob house has the pipes and wires laid directly in place. Building with cob tends to be a much calmer,smoother process than a typical house, as there's no need for power tools or as large of a scope for error.

Q:How much does it really cost to build?

A:Compared to more modern building materials, cob cottages are one of the most inexpensive to build. This is especially true if you have a group of friends to help! The most expensive part of your house will be the other components required such as windows, doors, flooring, etc. Many builders utilize recycled materials to help keep costs low.