The film "Garbage Warrior" (about Arch. Michael Reynolds and his concept of building houses out of old tires filled with sand), generated quite a stir here in C.R. similar with the introduction of 'Super-adobe' to C.R. by Jaroslav Dusek, (a Czech actor seemingly needing to profile his green image with a unique 'gig'). This again has a trickle feed to me, as I'm frequently being asked for my opinion, or worse yet: To build one! Here's a thorough explanation of why I do not find it is an appropriate approach for C.R. as well as for most other temperate climate regions.
"Yes, the holistic thinking of an Earthship is excellent; that a house should be self-contained as a ship, which means including passive solar heating, rainwater catchment, solar/wind energy production, in-house reedbed cleaning system, build in planting area/greenhouse etc. And on top of it built by a waste product: Old tires!
I find it's a general problem that people wants to take a concept from one location and apply it everywhere. It once made me formulate the saying; "Don't build igloo's in a desert!". Back in year 2000, when I visited Mike Reynolds at the 'ground zero' for Earth ship development; 'The Greater Earth' in New Mexico, I understood why they used tires; There were not enough clay for miles to ram any earth, no trees of significance. Basically a desert. That's also the reason why they place the water cleaning system in the house, as well as the rainwater catchment. This is much the case for the 'Superadobe', a technique developed in a barren part of Southern California, where earth gets poured into an 'endless' plastic tube, (typically mixed with min. 15% concrete), and then made into load bearing domes. Excellent technique for low-income homes in tornado endangered hot Florida, but definitely not in cold climate countries.
Here in Czech we have other issues to face. This year our homestead had 200% of normal rainfall destroying our fruit and vegetable harvest. The year before we didn't have enough rainfall to grow summer vegetables. But our well water was always sufficient. In other words, my focus is on creating storage for rain water around the house and garden, including ways to divert the water when there's too much. I'm also quite happy to have the reed bed cleaning system outside, as it takes up space and can cause a slight non-pleasant smell, which would accumulate in the interior environment, but vanishes in the garden. Besides; we can't really grow bananas here anyhow! +We use separating composting toilets, so it's only waste water and urine which goes in the filter. Our toilet produces final compost in a 4 year cycle, which goes straight in the flower/herb/berry garden.
OK, Jakub Safar, the initiator of a Czech earthship wiki-site, wrote that he had decided not to use the tires, rather to build the house from Compressed Earthen Bricks (CEB), home made in a manual press. Thank goodness that he's past the tire issue in Earthships. I have a hard time with many of the dreamers who can't seem to think rational about climate appropriate construction (Here's the most public one of them in a freezing cold structure!). I worked for Oskam in DK, an inventor of one of the worlds best CEB machines, which now is being used by Claygar here in Czech. You can go ahead and make your own press, but I wonder how the balance between your labour value is, as compared to buying them from Claygar? -This is not to say anything against building your own home; here's pictures of a cob cottage one of our interns did this summer: (Lovely, built by feet and hands, but uninsulated = dreamer!)
In other words, I also find you're missing a significant point (or at least haven't articulated it).
Insulation?
As our straw-bale house still isn't finished, I'm now sitting in a 130 year old house with 80 thick walls. It's bloody cold, if we don't constantly heat it, as the heat is on a constant travel out. Sure the earth is good for interior climate, but I can't wait to move into the straw bale house next spring; 45 cm insulation and 3 cm earth for interior climate/moisture/heat regulation. Personally I'd only use the CEB's for interior, but then again; typically the walls don't need to be load bearing, so in our case I recycled old adobes from a nearby renovation project, and we also build some curved walls with wattle and daub. Upstairs interior walls are from ekopanels (compressed straw) due to less weight. And here's a confession: I use the rammed tires as a foundation for heavy internal walls. We ram them at our workshops, and I tell the students that this is a vaccination against ever building a whole house this way!!
And after lifting a 5 kg sledge hammer 200 times just to fill one tire, then everyone understands my point... Fact is that an Earthship building crew looks like a group of bodybuilders who escaped the gym (but still have plenty of steroids!).
Yes, daylight in the house is central, and I might not have designed our new house optimally. It is however designed better than an earth ship, as we have a 1,2 meter overhang on the South side, insuring that the summer Southern sun doesn't heat our house, but that the low winter sun reaches all the way in to the rear wall of the house; even through a window in a trombe wall, which aids in heating the house. There's general agreement that a huge problem for the future is that the cost of cooling our houses are going to reach close to the costs we present have of heating them, predominantly due to superior insulation, and too much light exposure; too big windows; I'm aware that one of the non-optimal issues of an Earthship is that the 'bottom' of it can be chill, and the front too hot: It's why they changed the angle of the windows and added a manually operated ventilation shaft in the back 10 years ago (see prototype on photo).
Last but none-the-least: Several tests has shown that you need about 3 cm thick earthen walls for heat accumulation (same thickness as an earth plaster on straw bales), and that what's beyond 3 cm doesn't really have any effect. It's also proven that a solid earth wall is a solid cold bridge: The earth has to eb interrupted by a layer of insulation, to stop the heat/cold from migrating from side to side.
This is what eliminates Superadobe and earthships in C.R. And why bother building a 50 cm labor intensive wall, if only 3 cm is needed?
All-in-all; the Earthship concept is great, but the design is not suitable for Czech Republic. As comparison: Our house is heated with sun and wood, we gain the power for our office from PV panels we found in a container rigged up to batteries and grid for a 15.000 investment ...However our house is not in the ground where it would be flooded every spring on our property (we're at the bottom of a hill), our house looks relatively 'normal', apart from the fact that I made the straw bale insulated roof curved. -This helps the resale potential, which is a point only few of us can afford to ignore.
Concluding; I'm at any time recommending the term 'Natural Building', (which includes Earthships), rather than recommending a very specific approach to natural building, designed for very special circumstances, like 'Earthships' or 'Superadobe'
And I believe that the reason why folks like Jakub Safar promote Earthships, is likely that this was how you discovered the world of Natural Building, and our mis-communication is due to the fact that even though he decided not to use the basic concept of Earthships, (the tires), then he still call it an Earthship...
...Kind of like calling Tofu for cheese, though it hasn't got milk in it and shouldn't be eaten raw, isn't it?
