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.