Earth builders utilize desert soil to create lasting homes
By Marissa Bond
The Las Cruces Bulletin
Editor’s note: This article is from the Life is Good in Las Cruces Community Guide, which is now available.
The high desert vastness, patched green only by lowcrouched shrubs and spindling cacti, seems as unlikely a place to find the materials to build a home as an ocean. The Earthbuilder’s Guild sees promise, however, in the sun-baked soil and river-sogged clay.
Primarily, earthbuilding consists of rammed earth, traditional sunbaked adobe and compressed earth blocks. Less common methods include light straw and clay constructions and terrones.
Rammed earth and compressed earth blocks are similar in material composition — generally sand, clay and water.
For rammed earth, forms outline walls. The framework is filled with a mixture of sand, clay, and water. Pneumatic tampers compress the earth into a solid layer. Another layer of mixed sediment is added to the top, and the process repeats until the walls reach their desired height.
Compressed earth block, however, squeezes the material into a block similar in size to an adobe brick. Traditional adobe has more clay in its composition, and the blocks are sun-dried.
Terrones construction is no longer a common method, but many historic structures built along the river were made from terrone, which was a portion of the riverbank thick with grasses. Mud clods veined with roots and grasses were cut out, dried and then stacked and used like bricks.
A light straw clay construction, meanwhile, is an earth mix that has very high content of straw. It does not operate as a load-bearing construction, but as an insulating standard to be used in conjunction with a beam-and-post construction.
While earthen homes are popular worldwide, with a history extending back thousands of years in a variety of climates, they are very well suited to the temperature fluctuations of the desert.
“Earth is a fantastic insulator,” said Sean Kaltenbach, chair of the Earthbuilder’s Guild and owner of
New Mexico Earthworks. “For example, if you have an adobe home, and if you heat that home up with a fireplace in the winter, what ends up happening is those earthen walls absorb that energy, absorb that heat, and essentially stores it like a battery.
“It becomes sort of an energy bank for either heat or coolness. … It makes more of a consistent, regulated temperature within the structure,” he said.
“If your power goes out, you’ll only lose three degrees by morning, while your neighbor’s house will be cool by morning,” said Gary Wee, Earthbuilder’s Guild member at large and owner of Earth and Sun Construction.
As a construction, earthen materials utilize the resources the desert has available — sand and clay.
“When your wall construction is made of a local material, the sustainability of that, and the actual impact that it has on our environment is profound,” Kaltenbach said.
Earthbuilders also boast of sanitation and health benefits in earthen construction. The thickness of the walls and complete seal with the ground means that rammed earth homes are extremely resistant to bugs and pests. “It is so solid to the ground there’s no way for bugs to get in,” said Pat Bellastri- Martinez, secretary of the Earthbuilder’s Guild and owner of Soledad Canyon Earth Builders.
Kaltenbach uses traditional earthen plasters inside his adobe and compressed earth block homes.
“I specialize in an earthen system,” he said. “The combination of either traditional earth or traditional lime with the traditional earthen construction allows for healthy air environment inside the home.
“A lot of our modern construction materials are synthetically made, are not breathable, don’t have a capillary action, and so as we move into energy efficiency in new constructions, we end up sealing up these new homes so tight that the air quality becomes of a particular concern. … Our earthen walls absorb impurities. If you use traditional lime plaster, that’s been used in our history as a sterilizing application.”
Many of Las Cruces’ old buildings are earthen construction, primarily adobe, and these older homes still have much to offer new or long-time residents. Kaltenbach said when people purchase and older adobe home and choose to do renovations or updates, the homeowners might choose a contractor unfamiliar with adobe – and ending up rapidly perpetuating the demise of an adobe structure. Kaltenbach encourages adobe homeowners to choose adobe specialists, such as members in the Earthbuilder’s Guild, when renovating their structure. “It means doing it with an understanding of moisture and the earth, and how those work in relation to one another,” he said.
With proper care, however, earthen-material homes can last hundreds of years — a reliability and comfort that some homeowners say they can feel.
“It’s got an embracing kind of feeling, a sense of permanence. It’s for people who want that permanence,” said Bellastri- Martinez.