'When people paint it, they stop the dynamic of the adobe. They also seal in moisture -- adobe is wicking moisture up from the ground, destroying their walls, and they can't see the damage," says adobe-restoration master Pat Friend. "The worst thing to do to any adobe home is to paint it." On Saturday, March 11, Friend will present a hands-on adobe brick-making seminar for the San Diego Archaeological Center. Adobe bricks are made from soil (consisting of sand, silt, and clay) mixed with water and left in the sun to dry. According to adobebrickkits.com, "In the summer it takes a minimum of a week of hot dry weather for the bricks to cure adequately for handling and use." If one wishes to build a structure out of this earthen brick, it is important that the ingredients used to form the brick be found at the location on which the structure will be built. "If you're using the onsite material, it's considered durable for that area."
Even if the proper soil is used, things can go wrong. "People want to have nice, pretty plants, so they turn on their sprinklers and forget about their house. They'll call me and say, 'Oh my goodness, my walls are dissolving,' and I say, 'Turn your sprinklers away from your house!' If you build your home [out of adobe] and you've got a good overhanging roof [which offers some protection for the walls], I'll say that house is going to last you a hundred years. My walls are already 20 years old."
According to oldhouseweb.com, the same methods for making adobe are used today as were used in the 16th Century. "Because adobe bricks are not fired in a kiln as are clay bricks, they do not permanently harden, but remain unstable -- they shrink and swell constantly with their changing water content. Their strength also fluctuates with their water content: the higher the water content, the lower the strength."
"Adobe is a porous, breathing thermal mass," says Friend, who is adamant that adobe is the best material for building. "It is a wall made out of earth, but it stores the heat of the sun, and through its porosity, it breathes. When the temperature of the interior of the house drops, warmth is released from the walls into the interior. Wood rots. Homes out here rot. They get termites; they burn down. An adobe home has no termites; it won't burn."
Friend was recently asked to restore the Santa Margarita Ranch House Chapel and Bunkhouse at Camp Pendleton, a structure that was originally built in the 1860s. "It took a long time to get the money for those," Friend says of the federal government grants that paid for the restoration.
"I made whitewash from the original formula used to protect those adobe earthen bricks. People only used the best clay soils that were on site, and water. Any moisture would melt it. So we stucco the walls with lime whitewash, and that would protect them. Latex paints today are like a rubber skin -- it has no porosity, and that's the virtue of the lime whitewash. It is the closest porous, breathable, and compatible product to go against earthen brick." Friend offers this "Original Formula White Wash" at $125 for five gallons.
"Our choices should be for maintaining harmony with our mother, the earth. Her health is our health. I am out there like a warrior saying, 'Please, people -- will you understand that what you're standing on is your building materials?'" Friend is a member of the Native American tribe Tigua. "We lived along the Rio Grande River, pueblo style, and our people were farmers. They scraped up river mud and made the bricks. My mother's family, my grandmother and great-grandmother, told me stories about brick manufacturing in the back yard because when a new baby was born, another room was added to the basic unit. The stories were told to me to keep the culture alive."
If an adobe structure is to last, it is imperative to keep it dry. If the material is not properly dried after a few days of rain, water damage can accelerate deterioration and lead to the collapse of the structure. Wind can also have an erosive effect, as can vegetation, insects, and vermin. It's possible for seeds encapsulated in the adobe to germinate and grow. According to oldhouseweb.com, "The possibility of termite infestation should not be overlooked, since termites can travel through adobe walls as they do through natural soil."
Friend insists that if an adobe structure is properly cared for it can last for a lifetime or longer, as in the case of the structures she helps to restore. "Adobe has been used all over the world since the beginning of time. There were people housing themselves before Home Depot." -- Barbarella
(Hands-on lesson of adobe history and brick manufacturing)
Saturday, March 11
11 a.m. to 1 p.m.
San Diego Archaeological Center
16666 San Pasqual Valley Road (1.5 miles east of S.D. Wild Animal Park)
Cost: Free to members; suggested donation of $10 for nonmembers
Info: 760-291-0370 or www.sandiegoarchaeology.org