Frequently Asked Questions
What is Natural Building?
Natural building is a fairly new term that sums up an approach to building that focuses on using locally (and carefully) harvested and recycled materials, simple tools and techniques, sensible design strategies and community-based lifestyles.
The most common materials and techniques used are cob, adobe, straw (or other fiber), rocks, bamboo and locally harvested wood. Most of the time some combination of these materials is used.
For “quality of life” reasons and out of concern for the environment, natural builders tend to design carefully crafted cottages, rather than large, boxy houses. They pay close attention to the orientation of the house, window placement and energy needs.
Although there are some similarities, Natural Building is significantly different from “Green Building”. Green builders generally use the same construction techniques as conventional builders, but use more responsibly produced industrial products.
Due to its simplicity, affordability and its creative possibilities, Natural Building is a wonderful choice for owner-builders.
The Natural Building movement as a whole has a strong community feeling. Many builders and teachers get together on a regular basis to share information, learn from each other. Annual meetings, often called Colloquia, are held across the country.
Many people in the Natural Building movement also have connections to Permaculture, eco-forestry, organic farming and the fair trade movement.
What is cob?
Cob is a building material that is made of a mixture of sand, straw and clay. The materials are mixed wet, by foot or with a machine (tractor or mortar mixer). The word “Cob” comes from an old English word meaning “Lump” or “Loaf.” We often form our cob mixture into loaf-shaped blobs for ease of transport.
The wet cob mixture is used to build thick earth walls; the building technique is very similar to sculpting with modeling clay. Because cob building requires no forms, we can build our walls into any shape we choose. Curves, niches, arched windows and built-in furniture are common features in cob buildings.
Cob building requires no cement, no expensive tools or materials and is a “people friendly” way of building. Often we can find the bulk of the materials on or nearby the building site.
Once the material is dry, cob is incredibly strong. Although there is little conclusive research about how cob buildings perform in earthquakes, there is much empirical evidence that they would survive very well. Many cob buildings in New Zealand have survived major earthquakes. The country of Yemen in the seismically active Persian Gulf has many 10 story cob buildings that have survived for over 500 years.
One of the most commonly asked questions about cob is “What happens when it rains?” The cob tradition originates in England and Wales, no dry countries by any standard. These countries have whole villages of cob buildings, many of them hundreds of years old. The secret is the same as that of any building style: A good roof and a good foundation are the keys to survival in wet climates.
Cob works well in all but the coldest climates. If it gets too cold, it is easy to add extra insulation on the outside of a cob building. Cob houses benefit greatly from good passive solar design.
For all these reasons and more, cob is an almost ideal building material. It is easy to learn, inexpensive, beautiful, healthy, comfortable and the materials can be found almost anywhere. It is no wonder that about half the world population lives in an earthen house.
In the United States, cob is experiencing growing popularity. Besides the above mentioned advantages over conventional building methods, cob can offer people a way out of the crazy real-estate market, an unhealthy lifestyle and a job with no joy. Many people who never considered themselves builders have created a cob house for themselves. There are now hundreds of cob buildings in the USA, with a concentration in Oregon and California.
Cob is useful for much more than houses, too. We teach how to make cob ovens, fire places, earthen plasters and cob floors. Garden walls are also an extremely popular application of cob. Cob can easily be integrated with conventional houses and used in a “natural renovation”.
What materials do most people use?
The most commonly used materials are earth, sand, straw, stone, wood and bamboo. Earth, sand and straw mixed together makes cob, which is used to sculpt walls, make built-in furniture, fireplaces, big bread ovens and adobe bricks. Straw bales are used like bricks to create super-insulated walls and are then plastered with earthen or lime plasters. Stone is used for foundations and rock walls. Wood, often in the form of locally harvested round poles, is used to support roof structures and frame windows and doors.
I have never built before, and I am not very strong. Can I do Natural Building?
Yes! Natural building aims to be inclusive and low-tech. We emphasize cleverly designed smaller buildings and easy to learn techniques. The building process is fun and health-giving. A few simple hand tools are all we use on the building site. Strength and experience do help, but so do patience, perseverance, friends, and a positive attitude.
What do you mean by “affordable?”
You can build a snug cottage for a small family for as little as $5000 in materials. There are people who have spent less than $1000 for a beautiful hand-built natural cabin. Things that greatly influence the affordability of your house are design, the amount of labor you do yourself and the amount of second-hand (or free) building materials you can gather before you start.
I already own a house. Can I use Natural Building to fix it up?
You don’t have to build a house from scratch to make natural building part of your life. Many people have built saunas, tool sheds, play houses, gazebos, earthen ovens, fire places, and garden walls near their existing homes. Many Natural Building techniques can be used to renovate conventional houses, such as earthen plasters and floors, natural insulation, internal cob walls, and more. Read our article about Natural Renovations.
What do you mean by “appropriate technology?”
A house is more than four walls and a roof; it includes many “systems” that enable us to cook, have lights, running water, and stay comfortable in different seasons. In conventional houses these systems are very expensive as well as dependent on huge amounts of energy input; even then they often don’t work very well. “Appropriate technology” refers to systems that are easily built and maintained, cost very little, use local resources whenever possible, require little energy input and work continuously and consistently. An added benefit is the lack of high energy bills.
Can I really learn how to build a house in one workshop?
Yes you can, and many have done so. Often people need some help with carpentry, electrical and plumbing. These are skills you can learn on your own, or can be contracted out to people in the community. Taking additional workshops always helps and will make you more confident. You can also learn a lot by helping someone else build their house.
How do you deal with building codes?
Many people ignore building codes, as they sometimes make you do things that don’t make sense. Others work with building officials and try to educate them about natural building. This can be a difficult road to take, depending on what you want to build and the spirit of your local building department. Building on land that already has a code approved home on it makes it easier for you to stay below the radar. So does living out in the sticks. If you go the “outlaw” route, keep it small, quiet and invisible from the road (good ideas for any building project). As more people desire naturally built houses, people are finding new and creative ways to work with and around codes. If you want a code approved natural house, don’t be a purist: build a “hybrid building” that uses different techniques to help you get what you while satisfying the requirements of the building department.
How do I find land to build on?
If you want to live close to a population center, the cost of land can be high. Try to save and buy within your means. Avoid banks if you can; many landowners who are selling will carry a loan. Or try to borrow money from family and friends. If you keep the cost of your house to $5000, your total monthly payments can end up being very reasonable. Even better than buying your own land is to see if you can build on someone else’s. Many people have too much land to take care of themselves and wouldn’t mind sharing it. With today’s real estate prices, this is becoming a very sensible solution.
How long do natural buildings tend to last?
There are examples of earthen buildings that are more than 1000 years old. Straw bale is a newer technique: the oldest straw bale buildings are almost 150 years old. With a good foundation and a good roof, natural buildings will last a long, long time. Geological materials such as stone, earth and sand tend to last longer than biological materials, such as straw and wood. It is interesting to note that the average house in the United States lasts about 50 years before it is bulldozed down to make room for something bigger or better.
Will cob work in very cold climates?
Yes it can, if the building incorporates good passive solar design and is built in a climate with sunny winters. In places with regular freezing temperatures we often recommend to build a thinner cob wall and then wrap the whole building in straw bales. This can make for a very cozy and efficient house.
Will cob work in humid climates?
Yes it will. If it is very humid, the cob will dry much more slowly during the building process. Wind (or even fans) can speed thing up significantly. Once dry, cob will provide for a much cooler and more comfortable house in humid summer heat, as the clay can absorb a lot of the humidity.
Can I bring my children to the workshop?
Yes you can, and we encourage you to do so. In past workshops, children have brought a richness to the event that was enjoyed by all. Please read about “bringing children” on our workshop page.
Can you do a workshop on my land?
We can do workshops all over the world. To find out how that works, please click here to find out more about how this all may work!
Cob seems a little slow. Are there machines that can speed it up?
Many people have used tractors, mortar mixers and bobcats to mix cob. It can speed up the process multiple times, and the walls of a modest house can be up in a matter of a few weeks. However, it comes at a cost. Because the walls go up so fast, you have less time to sculpt your house slowly and deliberately. The speed you gain can quickly be lost by a back injury or other accidents (back injuries can last a lifetime and are very costly). Big machines also make it harder to have children and elderly people on the job site; and as the building site becomes filled with noise and fumes you will find yourself resisting the building process and enjoying it less. Having said that, if you are thinking about being a “cob contractor,” using some form of mechanization would be essential.
Do you build as a contractor for others?
No we don’t. However, we often consult on job sites for anywhere from one day to several weeks in order to help people on their way and to be a guide at critical junctions in the building process.
Do you consult?
Yes we do. We prefer to consult on projects that are aligned with the spirit of our work. We can also assist in master planning, site planning, design, energy systems and more. We have a long list of friends and colleagues that we can recommend in case we don’t have the expertise or time to help you. Contact us if you have more questions about how we can help you.
What is “Light straw-clay?”
Light straw-clay is an infill technique that is made by mixing loose straw with a clay slurry (slip) and then tamping the mixture into a form. It’s an easy-to-use material, insulates reasonably well (better than cob) and provides some thermal mass. It works very well for renovations of existing houses. Our workshops always include a hands-on demonstration of this technique.
Will cob work in Hawaii?
Cob can work anywhere you can find the ingredients for cob: clay, sand, and fiber. We have heard that there is clay in Hawaii, but have never worked there. Read about cob in humid climates for more information.
What are earthen floors?
We get a lot of questions about earthen floors. An earthen floor is essentially an earthen plaster that is troweled onto the floor and sealed with oils. Many people ask: “aren’t they dusty?” The answer is no! Earthen floors are wonderful. We have lived with earthen floors for more than 5 years. They are warm in the winter and cool in the summer, durable and hard, yet soft and easy on your knees and back (unlike concrete). They are very affordable, easy to repair and not too hard to install. We cover earthen floors during our workshops. Read our Earthen Floors article for more information.
I want to get out of the rat race and live more simply. Where do I start?
The simple answer is: With the first step. But even that first step is not so simple. A very helpful book to read is “Your Money Or Your Life” by Joe Dominguez and Vicki Robin. The book will help you reconsider the financial choices you make and can assist you in “getting your life back”, so to speak. Other than that, connect with others who share your goals, by taking a workshop or finding local groups of people who choose to live more simply. Everything becomes easier if you have the support of those around you!
Do you do a work-exchange in lieu of workshop payment?
Occasionally we do a partial work-exchange for people who live outside the cash economy. Please contact us if you are in that category.
I can’t find clay on my site. Can I still do cob?
Occasionally a site does not not have any clay. In most cases you can find it nearby and bring it to your site by truck. That is usually still preferable to cutting down the forest somewhere far away for a stud frame house. With no sand or clay nearby, you may want to consider another Natural Building technique, based on your available resources, your skills, your climate and your creativity. Let us know if we can help evaluate your options.
How can I make a living as a natural builder?
Start with a workshop or apprenticeship and then build or help build a house from start to finish. Get a business card and a small pick-up truck and get started! Begin with small projects or work alongside a more experienced professional. Consider a specialty, like cob, straw bale or natural plasters. The demand for skilled professionals is there. If you are willing to learn and work hard, it is all possible.