Sunday, August 29, 2010

Earthshipping, FedEx Style

Just finished up my last week in Taos, working on Earthships, and am "shipping out"...
Here's the final review:

Structure: The tire pounding is both fun and exhausting, and it really results in a shared experience/hardcore bonding since no one else knows what it means to pack hundreds of tires full of dirt and repeatedly pound it with a sledgehammer. The tires are great because pretty much NOTHING could destroy those walls, and it is a reuse for the millions of tires that are lying around on our earth. That said, it is extremely labor intensive and in the end, the tires give you a wavy wall, so in order to smooth out the walls the builder must use extra materials (like cement and cans). Unfortunately, I see no way around that except for leaving walls wavy, which most people would not desire. The bottle walls--both glass and cans--I think are a little outdated. Not the idea of needing a filler in the cement, but the fact that they use recyclable materials. Sure, they were used once and often recycling them means shipping them overseas and having them melted down and reprocessed, but if we are talking in terms of embedded energy...aluminum is a material with one of the highest levels of embedded energy (also, portland cement...yikes)!

Water infiltration: I think one of the largest problems that the earthship crew needs to overcome. Vertical glass has been done forever, and it is relatively easy to waterproof around it. Slanted glass? Not so much. There seems to be always leaks, and the first thing to go in an earthship is the wood sills below the slanted glass. The newer earthships are building with that plastic decking material, which solves a lot of the problem, but I still see problems in the future with water infiltration. There are so many ways in which water can infiltrate (condensation in the greenhouse, roof flashing, gutter systems into the cistern, using silicone to fill in large gaps, etc.), and if the focus is on longevity of the house, then this is something that needs to be tackled.

Systems: Earthships are the furthest developed in the green building realm on integrating systems within their structure. I did not work much with the electrical side of the systems but spent a few days working on plumbing systems, and I am very excited by what I saw. There is a fully integrated rainwater catchment/cistern system which is filtered and used as drinking water with "waste" running into the greywater system that feeds the toilet, which then exits into a traditional blackwater system (septic/leech field). In my opinion, the composting toilet is a better solution, but I understand their reasoning for the blackwater (less maintenance, the balance of woodshavings to excrement can be thrown off if there are large parties thrown at the house, unintentional misuse of the composting toilet, etc). The earthships also include a glycol solar thermal panel system which both heats water for showers/sinks, and melts the snow off the roof in the winter. Combining all these systems is complicated, but it is incredible how well they work! The other AMAZING part of the systems....is that there is NO heating system. That is the most amazing and inspiring part for me, especially thinking of the $400+ heating bills people are paying in uninsulated homes in Buffalo...

Plastering: I hate stucco. Can't there be a more natural alternative? Yes, but if you are championing longevity of a product, the stucco may last longer than a more natural plaster/limewash finish...don't know how to choose on this one...

Cost/complexity: Originally, the earthship was designed to be able to be built by the common man. That is no longer the case...the systems are too complicated. Also, the cost ($200/sqft) is very prohibitive, though that is with hiring the crew to build the structure, so I can imagine it would be much cheaper building on your own. Though, if it takes 5 years to build your own...sheesh. These two factors are major inhibitors to increasing the number of earthships in the world...

Despite some things that need to change I think the earthships are headed in the right direction, and I give the crew and Mike Reynolds a whole lot of credit for designing these amazing structures. I will most definitely be taking all 6 elements of an earthship (thermal/solar heating and cooling, on-site energy generation, contained sewage treatment, reusing materials, water harvesting, and food production) and incorporating them in all future building/rebuilding that I do.

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