What is Adobe?

Quentin Wilson and Associates, specializes in solar adobe design and construction. He grew up in the South Valley of Albuquerque, New Mexico where he watched adobe bricks being made. In the fifth grade, he made miniature adobes on cookie sheets in his mother’s oven in order to construct house models for a class assignment. By age thirteen he made full-sized adobes in the back yard and ruined the grass. Later, he traveled a bit, went through the Army, and graduated eventually from the University of New Mexico with a major in physics, minors in math, chemistry, and education in 1970. After teaching high school two years and community college math for three more, Quentin moved into professional solar adobe construction in 1976 as the Project Manager and Instructor for the Sundwellings Demonstration Project at Ghost Ranch, Abiquiu, NM. He became a licensed general contractor in the State of New Mexico in 1982. He has been building homes and teaching seminars and workshops ever since. In the fall of 1995 he established and taught the full-time Adobe Construction Program at Northern New Mexico Community College. His website, quentinwilson.com, lists the course schedule and many other resources related to working with adobe.

Q: What are adobe bricks?

A: Dirt and water create mud. Mud shaped like a brick becomes a brick when it dries out. More dirt and water make mud that becomes mortar to stick adobe bricks together to create a wall. Thousands of years old is the technique. Just think back to all the photos you have seen in the National Geographic of Egypt, Peru, Uzbekistan, Chile, Argentina, Sudan, Yemen, New Mexico, Germany, Southern France, India, China, Bangladesh with the man in the flood with a sewing machine on his head, Arizona, sod in Nebraska, cob cottages in Ireland, England, Wales and run down to Sumter South Carolina to check out the Holy Cross Church. Because Scots are so cheap, castles in Scotland are built of adobe brick and veneered in stone. Actually, Germans, French and Mexicans are known to do the same. Adobe is everywhere and is part of everyone's heritage. Even Norway.

Q: What does ADOBE means or stand for?

A: Adobe soil has clay and sand in such proportions that when mixed into mud then dried out it forms a brick or a wall.An adobe brick is made of adobe soil and is sun cured on the ground. Adobe mortar may have more clay than plaster, floors or bricks. It sticks adobe bricks together to create a wall. Adobe plaster is that which uses clay as the primary binder. An adobe floor may be made of adobe bricks laid flat on a dirt, sand, or gravel base. Joints may be filled with adobe mortar, cement grout, sand or nothing. Adobe floors are more often made by pouring adobe mud over the base in one thick or several thin layers to give a monolithic floor somewhat like concrete. An Adobe home is made of adobe bricks or monolithic adobe walls. Adobe stands forever if it has a good foundation and a good roof and has occupants who give it a bit of periodic maintenance.

Q: Could you help me find some adobe soil. I am trying to build an adobe oven for pizzas, bread, meats, etc. I am having a hard time finding the adobe soil. I live in southeastern North Carolina.

A: Take a large tin cup and drive to NM border. Knock on any door and ask for a bit of adobe dirt. Everyone is in the Christmas spirit so you won't be refused.

Q: My partner and I are soon to build a house and we would like to know about the advantages of building our home out of adobe instead of brick.

A: In some cases, it can depend upon your location. Adobe bricks can be made most anywhere on the planet by the people willing to do the work (or pay someone else to do the work.) With a good foundation and a good roof adobe lasts at least as longs as wood walls which rot, steel walls which rust, straw walls which mildew and brick walls which eventually loose their mortar.

The adobe bricks can be made from your own dirt on your own site, they are dried by solar energy and the other energy input is from human metabolism. That is so green and so autochthonous as to be that which there is none greater.

You can read a book, take a class or talk to someone and within 20 minutes you will be as good an adobe mason as a professional. There are only seven parts to an adobe house so the learning curve is not steep: Foundation, wall, brick, mortar, lintel, bond beam, roof beam or viga or joist, insulation and roofing material.

Adobe bricks are heavy. The construction of a wall is brutal. Well organized with a couple of friends, the walls are up in 3-1/2 days. Not so well organized and they will be up in 3 weeks. Nine months later, you will still be trying to finish the details. Plumbing, Electrical, Heating, Plastering, Doors, Windows, Floors.. the list never ends. In most homes the wall costs are only 7 to 11 percent of the total budget so if you are trying to save money, don't look too hard at the wall line item. You have to vigorously attack each and every line item. Any extra nickel spent is compounded by all the other line items.

When you are done, the tougher the job, the more you have to look back on.

Q: In our villages in Morocco - North Africa -. we just use the earth and stones to build a house. I want to learn from you how to make fired bricks that is friendly to the environment.

A: Earthen homes are ideal in the climates that have high temperatures in the summer and cold temperatures in the winter. The massive walls of earth average the extremes of daily temperature fluctuations. Properly designed - mainly elongated in the sides that face the sun - the job of staying warm in the winter and cool in the summer is more readily accomplished.

There is no environmentally friendly way to make fired clay bricks. The massive amounts of bricks needed to build structures would require massive amounts of wood to heat a kiln hot enough and long enough to produce fired bricks. Those parts of the world where fired bricks were made consumed large amounts of firewood and as time went by people had to go further and further to obtain the firewood. A modest home of 100 square meters floor space would require about ten metric tons of firewood and a large kiln to fire the bricks. Traditionally the raw bricks are stacked in such a way that the fire at one end will flow through them to the other end. Once the bricks are stacked, walls of raw bricks are built on four sides to hold the heat in. After the bricks are fired, the walls of the kiln are taken down and are stacked to be fired in another kiln. These bricks are already partially fired. This requires much labor, time and firewood. 

The environmentally friendly method is to build with unfired bricks, adobe. The raw earth adobe is also better for the thermal performance of the house. A raw earth brick is slower to absorb heat and slower to lose heat so they provide heat to the structure for about ten hours. Fired bricks absorb and release heat much faster so they only provide heat to the structure for about six hours. In the summer when it cools off at night adobe slowly cools down and in the daytime as the temperature rises the adobe keeps the structure cool. Fired bricks absorb and release coolness too quickly. 

Adobe bricks are strongest when they have about 30% clay and 70% sand and gravel. They tolerate some silt and organic matter. If adobe bricks have less clay than 30%, they will not be as resistant to rain but they are still strong. If bricks have more than 30% clay they will crack when they dry out. Cracking can be controlled by adding sand and gravel or by adding straw from wheat, barley or perhaps other grain. In many locations that straw should be returned to the field to keep the soil healthy so I avoid using straw whenever I can.