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.