In the attempt to better understand the earthships’ concept, Rachel – the firm’s architect - and I had a few trips around New Mexico visiting Michael Reynold’s Earthship Biotecture community in Taos and two extreme examples of inhabited eartships, in Madrid and Valdez (Taos).

At Earthship Biotecture, despite the ticket, we were just allowed to step into the exposition building, an architecture of unquestionable beauty, that impresses the visitors with its unusual shape, its bottle walls, its greenhouse with colourful flowers and plants and its alleged sustainability. In my opinion, though, despite the very windy day, the ambient was too warm and the greenhouse very humid. Also, the several buildings we could not visit in the community, mostly uninhabited, were a clear symptom of the concept’s failure. The traditional New Mexican adobe house seems much more eco-friendly to me, rather than the high amount of cement used in earthships. But we can still learn something from the earthship’ experience: water management, photovoltaic and solar systems or the fabrication of those amazing bottle walls, for example.

The earthship we visited outside Madrid is a very basic one. It is totally off the grid, which allows its isolated and amazing position. The house was built in around 10 years by the owner himself, who had no previous knowledge about constructions. After reading Michael Reynold’s book, he started building it four days per week while working at his own job in the remaining three. He did not make accurate plans before starting, which caused many problems along the years: he doesn’t have a plumbing system due to wrong sloping, he had to reglaze the south façade because of design mistakes and rebuild the entrance because the cement wall was slipping. The earthship has no foundations nor insulation. The tyre-pounding took him seven months (not a long time, considering he was working alone) but the tyre walls do not reach the ceiling. Earth plastering the walls took a lot of work, as did the construction of the timber roof. There is no ventilation inside the building, unless the doors and the two skylights are left open, but the environment is quite comfortable and the back up stove is almost not needed in winters, as the thermal mass effectively acts as a good climatic regulator. The rainwater collecting roof has allowed the owner to harvest around 7000 gallons of water, which he filters many times and then uses for all purposes, by carrying it to the inside by tanks. A photovoltaic panel provides him all the energy needed, but the eight batteries and alternator occupy a large space and are a bit noisy. The house is built according to principles truly worthy of admiration, but it requires many sacrifices and uncommon adaptability.

The earthship we visited in Valdez is the extreme opposite. It is more a piece of art, rather than a building, very rich in cultural and spiritual details. It was started in 1989, covers 6,079 square feet and is fifty per cent underground, carved into the south-facing mountainside. The position can be hard to reach in the snowy New Mexican winters and the owners encountered many problems after the realization of the nearby R.E.A.C.H. Earthship community. The walls consist of more than 3600 tyres filled up with earth and some cement; the house is heated and cooled in this high alpine environment by passive solar control, by the mountain’s thermal mass and by an electric baseboard heat; photovoltaic panels provide electricity; rainwater and snowmelt are harvested and distributed within the house; natural ventilation is provided by skylights and my personal feeling inside the house was that of comfort. All these sustainable aspects, though, disappear in background compared with the artistic magnificence of the house. 

Albuquerque might not be one of the first choices when people plan to travel in the US, but it has plenty of activities, attractions and curiosities that would keep a tourist busy for several days (even the less architecture-interested). Here are some pictures of what I have seen this far…

Dogwood, iris, waterlilies, butterflies at ABQ BioPark Botanic Garden: one and a half miles of paths through formal and whimsical gardens. The Zoo offers close encounters with exotic and native animals, which have been rescued in large part.

Saturday mornings at farmers’ market. A part from the organic food (veggies, fruits, honeys, …) that comes from the farms surrounding the city, has affordable prices and is chemicals-free, the relaxed atmosphere of the place is what struck me most: a country band normally plays at one corner of the park and many families or early morning people come prepared with  sheet to enjoy the pleasant time outside.

I spent an afternoon at Farm & Table, a kind of the italian agriturismo in the North Valley. The organization owns a lush 10 acre farm right in front of the restaurant tables, where many kinds of vegetables, greens and flowers are grown during the whole year, in greenhouses or not. The farm has supplied the restaurant more than 100 tons of food last year to create by scratch their seasonal dishes, while the rest was sold at farmers’ markets in the town. Americans have begun to value food culture?

The Tibetan Lamas of the Drepung Loseling Monastery played traditional Tibetan instruments by the University of New Mexico campus next week, while performing ancient temple music and dance, believed to generate energies conducive to world healing. The monks also created a mandala sand painting, a tool for re-consecrating the Earth and its inhabitants. For a mandala sand painting, millions of grains of sand are painstakingly laid into place on a flat platform over a period of days or weeks. Most sand mandalas are taken apart shortly after their completion, which acts as a metaphor for the impermanence of life. 

Also, three easy mandalas were prepared for the public and the free experience of sand painting, with both its spirituality and painfulness, was something unique. It is up to each one to consider it a touristic attraction or not.

Historic neon signs still glow on old Route 66 through Albuquerque, which is now Central Avenue. Route 66 was first commissioned in 1926, picking up as many bits and pieces of existing road as possible. The first route alignment of 1926-1937 ran north-south through Albuquerque, Santa Fe, Los Lunas and several Indian reservations: 506 miles of mostly unpaved road. Albuquerque boosters began pushing for a straighter route, and by 1937, the entire route from Chicago to Santa Monica was paved. The new road carried thousands of GI's longing for a better look at America. Today I-40 runs over much of the original roadbed.

I just finished a research about an old technique for building walls which we should keep alive and try to spread all over the world. I’m talking about rammed earth.

Together with its “sister” solutions, namely adobe and earth bags, rammed earth is a very eco-friendly alternative to the conventional wood or concrete framing.

Evidence of the early use of rammed earth has been seen in Neolithic archaeological sites along the Yellow River in China, dating back to 5000 BCE and much of the Great Wall of China is made using an earlier method of rammed earth construction.

From my previous studies I have knowledge of rammed earth constructions in the Portuguese tradition as well as in the Australian aborigines' past. In the southwestern United States, adobe walls far exceed the use of rammed earth, but now the latter is starting to appear in building codes.

Rammed earth is a method of building walls whereby a mixture of earth is compacted in layers between a temporary frame, usually made of wood or plywood; it must be sturdy and well braced, and the two opposing wall faces clamped together. Damp material is poured in to a depth of 4 to 10 inches and then compacted to around 50% of its original height.

Most rammed earth builders use pneumatic rammers to compact the earth within the forms. As each form is filled, another form is placed above it, and the process begins again. Once a wall is complete, it is strong enough for the frames to be immediately removed. Construction is best done in warm weather so that the walls can dry and harden.

The soil mix needs to be carefully balanced between clay, sand and aggregate.  Modern advances in the technology include the addition of a small percentage of cement, better structural design methods, the inclusion of damp courses and concrete footings and regulatory controls by building authorities. It is also possible to add a water repellent admix to the soil mixture.

The soils used are typically subsoils low in clay. Clay/sand ratio has the greatest contributing effect on how well an earth wall will perform.  Traditionally it has been established as 30% clay and 70% sand (when using cement as a stabilizer, clay content can be reduced as low as 8% to 10%).

Most site soils can be used in some proportion to create a useable formulation, checking first gradation, USCS soil type, and in some cases a plasticity index.

Clay particles help to bind together the soil matrix. Coarse sands with a good distribution of particle sizes are usually better than fine or uniform sand.  Cracked or crushed gravel is better than “pea” or river gravel because of its angularity. 

Because of their thickness and density, rammed earth walls provide high thermal mass: this means that heat or cold penetration of the wall is very slow and the internal temperature of the building remains relatively stable. Thickness and density also provide great noise reduction; plus earth doesn’t burn, is non-toxic, non-polluting and ‘breathes’. On the other hand, rammed earth homes might take more work to meet with approval by building officials, bankers and insurers.

Given the many advantages of this solution, why isn’t it widespread and records so few cases of use, in Italy for example? Is rammed earth not adaptable to many conditions? Or more likely the building regulations tend to exclude it to be better protected and cautious? I‘ll keep researching.

I have been doing a research about Earthships in the last couple of days. What does this mean? Legitimate question, as it is a completely unexplored field in  Italy and, I guess, many other countries.

Earthships are passive solar houses designed in the 1970s by Michael Reynolds – known as “the garbage warrior”- and now marketed by Earthship Biotecture (Taos, New Mexico). What is curious about earthships is that they are made out of natural and recycled materials, like earth, tires, cans, glass bottles.

They try to be off-the-grid homes, with no reliance on public utilities and fossil fuels (but they often have a backup heating, e.g. wood or propane furnaces) and based on the principle of thermal mass, as the northern, eastern and western walls are normally built with piles of earth-filled tires with earth berm and thermal wraps outside them. The southern side presents a glazed greenhouse, with high thermic contribution, where the owners can cultivate their own vegetables. The general design, which includes rainwater harvesting, grey water recycle, black water septic tank, solar panels for hot water, natural ventilation systems, photovoltaic panels or windturbines, is the one in the picture below.

 Here are some pictures that helped me to figure out the construction process and the final earthship layout.

These suggestive buildings, however, have many problems, that are even more acute during the first years, as the accumulation of heat in the thermal mass is not yet completed. It is not unusual, then, to have too cold temperatures during the winter, as there is no heating, and too hot ones in summer, because of the large glass wall on the south. The levels of humidity in the greenhouse and within the house are often documented to be very high, because natural ventilation doesn’t provide enough exchanges with the external environment.

Lower costs of construction are often a false illusion, despite the wide availability of volunteer labour who decide to serve this cause.

Last but not least, scientific researches raised that several health concerns would result from tire house construction. Namely, the carbon black, a pigment used in the manufacturing of tires, contains heavy metals such as lead, mercury and arsenic. These known carcinogenics, along with other aromatic compounds, such as benzene and toluene which are present in rubber tires, are feared to leak into the water system once the tire breaks down in several decades.

Recycled does not always mean healthy.