In a nutshell, we encountered two problems (which may or may not be prevalent with all Earthships)
1. Extreme temperature fluctuations. You're essentially living inside a solar collector. In the fall, the sun would blaze in through the windows, and I know you're supposed to have overhangs, shades and air vents and underground air circulation systems, all of which we used. The bottom line is you can't cheat physics. Even with the shades closed, the house is receiving over 300k BTU/hr of solar heat. This is just too much for any reasonably sized cooling system to handle. My infrared thermometer measured surface temperatures in excess of 140 deg. F on surfaces near the windows. In the winter, the same windows would leak heat like a sieve. Here in Montana when it's overcast, 10 deg. F, and the wind is blowing 30 mph the front of the house would barely reach 55 deg F. This was with the 30k BTU propane furnace going 100% duty cycle. I would work at my computer with long pants, a sweater, a blanket over my legs, and an electric heater blowing under the blanket :) The rear of the house is built into the hillside, so it would be warmer in the back, but you could never get the place past about about 65-68 in the winter no matter how much you tried. The sheer size of the front windows and lack of insulation again made the house design at odds with thermodynamics in my opinion.
For the sake of comparison, our place in the hangar has ~R30 walls to the hangar, and again about ~R25 walls to the outside. We have in-floor radiant heat provided by our geothermal heat pump. Earlier this month when it was -20 deg. F outside we were toasty warm at 74 (we have a newborn child in the house now). And we were using significantly less energy to heat than at the Earthship.
2. Mice. The house construction methods are inherently porous, and mice have infiltrated the entire structure. They live in the cavities the walls form (and the roof supports), along the utility raceways in the ceiling, under cabinets, everywhere. I surmise that the mice have tunneled through the back of the hillside, between the tires, and up into the hollow cavities which support the ceiling. They then use this space to move around the inside of the house structure to other areas. No amount of trapping poisoning, etc. has slowed the onslaught of mice into the house. If the only way to prevent mice from infiltrating your supposedly green house is to use concrete in its construction and set outdoor poison traps which potentially kill hundreds of mice and may harm animals which then consume the poisoned mice, is this really such a green alternative?
I've visited an Earthship being constructed in Big Sky Montana by Mike Reynolds this year. The design changes I've seen may partially address point 1, but as far as point 2 I'm not at all convinced that this new house will be any better. I admire his vision, and that he's been able to take his ideas so far. From an engineering standpoint, even taking into account the ecological footprint of the structure, I'm not convinced that his approach is the best when you look at the whole picture.
For the thermal properties of the southern window exposure, I've wondered about that and in particular how that was affected by both summer and winter conditions. The fact that the EarthShips were first built in Taos, NM, which does get cold, but not quite to Montana conditions, suggested to me that the glazing might be a problem in colder climates. I've been to the Rocky Mountain Institute in Snowmass, CO, which has more extreme conditions, and it too shares both the semi-subterranean nature and large southern glass exposure of the Earthships (Lovins grows bananas in the atrium, in a bit of cheek).
Specifically:
⚫ What is the glazing? I'd hope for at least double-paned on the windows.
⚫ Some sort of exterior shading -- and awning, tree plantings, or removable sunshades (bamboo, canvas, or similar) might help the fall exposure.
⚫ Creating an internal vestibule, closing off the front garden from the main living space with a second set of doors/windows, or increasing the airflow through skylights or other openings might help moderate internal temperatures in both warmer and colder months.
⚫ Internal window coverings could minimize heat losses in the winter.
65-68F is actually about a perfect indoor temperature for me (if not excessively warm), so I wouldn't be complaining about that, though I realize not everyone feels that way.
I understand you were renting, not owning, so not all of these modifications would have been viable, but ... so it seems.
The mouse problem seems trickier. A cat (or snakes) might help. For pest control, it's seemed to me that solutions aimed at reproduction (bait with birth control in it, for example) tend to be more effective, though if you've got a large external breeding population there's likely no way you could keep up. Knowing what kinds of openings rodents can get through, sealing off the structure seems all but impossible. Gives you an additional appreciation for why the Egyptians worshiped cats as gods, however.
These pushes for housing like Earthships are curious, especially in light of your comments (which mirror my expectations). Not curious by themselves, but curious in what they represent. Humans developed modern housing specifically to combat weather, slow ingress by pests, etc. I wonder if this Earthship (etc) movement represents a shift in where we are living. Ages ago, Europeans & Mediterraneans lived in a lot of unfavorable weather. Do more people live in temperate regions today, for a movement like this to happen? Why would that be the case? Perhaps shipping & the global economy have created a class of peoples that can live wherever they choose, where such a class of people did not exist before?
Humans developed modern housing specifically to combat weather, slow ingress by pests, etc.
That's part of the push.
There's also a lot of influence from real estate developers, financiers, and the like, to produce a, hate the word but it fits, "product" which will entice purchasers.
Much of the construction materials and standards are of the bare minimum to pass inspection. If you're in the trades you'll hear terms for wall blocks (the horizontal pieces placed between studs) depending on whether they're attached with one or two nails per end (the latter is marginally more expensive, but more robust), the thickness of studs, type of sheeting used, etc. Notably, contractor friends when building their own home significantly upgraded construction standards from code with an aim toward longevity and robustness.
The principles behind Earthships (and other sustainable designs) are to, generally, minimize both environmental impacts (through locally sourced and recycled materials) and ownership costs (through passive heating and cooling, water collection and reuse, etc.). Earthship Biotecture discusses the motives and evolution of their designs:
⚫ A structure built from largely recycled materials
⚫ Heating and cooling
⚫ Electrical system
⚫ Water harvest system
⚫ Contained on site sewage treatment system
⚫ Food production
The designs (or variations on it) are used in a wide range of climates, from alpine to desert to tropical to temperate.
As for the pest-resistance -- rodents and insects aren't unheard of in modern and/or traditional construction either, though it would be interesting to get a direct comparison of the Earthship vs. more conventional designs in similar areas.
No bridges. However there's this phenomenal set of clothes which only the most discerning can appreciate ... ;-)
You asked a question. I answered it based on both 1) my direct experience with construction and constructions standards and 2) material which is directly viewable on Earthship Biotechture's website.
As I stated above: I've known of the general concept for years (decades -- first heard about "junk houses" in the 1970s), but really only started revisiting it in the past year or so. And I'm genuinely interested in what the negatives of the design are.
I'm also generally somewhat skeptical of alternative concepts. Widely used designs are, if not always ideal, at least generally well understood particularly in their shortcomings and/or failure modes. And a lot of alternative concepts tend to be oversold, especially by their creators and proponents (and Reynolds is nothing if not a crusader).
If you're interested in the evolution of housing, it's helpful to realize that there's a vast diversity of designs applied to many different locales. Much of the variance is due to local needs, materials, costs, and capabilities. E.g., building with loose or lightly mortared stone and mud brick is cheap, but not particularly proof against earthquakes.
If you'll travel across the US, you'll find very, very similar designs being built independent of climate or location. I could speculate on specifically why, but a huge level of concentration in the homebuilding industry likely has a great deal to do with this. I'm also well-acquainted with fairly recent construction which has fared poorly even in only a few years, hence my comments on construction quality.
I live in a passive solar house with probably 10 foot overhangs on the south facing windows. I have no heat problems in the summer. Do you think sufficient overhangs would have solved the earthship problem? I also live in Montana.
1. Extreme temperature fluctuations. You're essentially living inside a solar collector. In the fall, the sun would blaze in through the windows, and I know you're supposed to have overhangs, shades and air vents and underground air circulation systems, all of which we used. The bottom line is you can't cheat physics. Even with the shades closed, the house is receiving over 300k BTU/hr of solar heat. This is just too much for any reasonably sized cooling system to handle. My infrared thermometer measured surface temperatures in excess of 140 deg. F on surfaces near the windows. In the winter, the same windows would leak heat like a sieve. Here in Montana when it's overcast, 10 deg. F, and the wind is blowing 30 mph the front of the house would barely reach 55 deg F. This was with the 30k BTU propane furnace going 100% duty cycle. I would work at my computer with long pants, a sweater, a blanket over my legs, and an electric heater blowing under the blanket :) The rear of the house is built into the hillside, so it would be warmer in the back, but you could never get the place past about about 65-68 in the winter no matter how much you tried. The sheer size of the front windows and lack of insulation again made the house design at odds with thermodynamics in my opinion.
For the sake of comparison, our place in the hangar has ~R30 walls to the hangar, and again about ~R25 walls to the outside. We have in-floor radiant heat provided by our geothermal heat pump. Earlier this month when it was -20 deg. F outside we were toasty warm at 74 (we have a newborn child in the house now). And we were using significantly less energy to heat than at the Earthship.
2. Mice. The house construction methods are inherently porous, and mice have infiltrated the entire structure. They live in the cavities the walls form (and the roof supports), along the utility raceways in the ceiling, under cabinets, everywhere. I surmise that the mice have tunneled through the back of the hillside, between the tires, and up into the hollow cavities which support the ceiling. They then use this space to move around the inside of the house structure to other areas. No amount of trapping poisoning, etc. has slowed the onslaught of mice into the house. If the only way to prevent mice from infiltrating your supposedly green house is to use concrete in its construction and set outdoor poison traps which potentially kill hundreds of mice and may harm animals which then consume the poisoned mice, is this really such a green alternative?
I've visited an Earthship being constructed in Big Sky Montana by Mike Reynolds this year. The design changes I've seen may partially address point 1, but as far as point 2 I'm not at all convinced that this new house will be any better. I admire his vision, and that he's been able to take his ideas so far. From an engineering standpoint, even taking into account the ecological footprint of the structure, I'm not convinced that his approach is the best when you look at the whole picture.