Silturq's Musings: Homestead Green Building: Earthships

This week, we're going to start looking at green building styles. There are several. When you are going the route of building your own home, and doing so on a homestead that you want to be off grid, the best way to go about that is to look at green building. The reason is simply because green building is not only better for your health, and that of the planet. They will also help significantly with the energy system you choose to use, lowering the amount of overall energy you will consume. New technologies and building methods have come a very long way in recent years. But they still don't do the job nearly as well as green methods. So let's look at some options.

I'm going to start off with an option that you may or may not have heard about: earthships. While similar ideas have been around for a long time, and have taken on different forms, "earthships" themselves, is an idea and design created by architect Michael Reynolds. They seem to be based on the concept of a solar pit house. I'm starting here because I love the concept, and there are a lot of ideas that go into an earthship that can easily be implemented into other building styles. Earthships are a bit controversial as to the overall sustainability and design. The basic concept is simple. There is an outer wall of recycled tires, filled and pounded with dirt, that goes around the back and sides of the building. A water barrier is placed on the outside of the tires, and then an earth berm is backfilled against this wall. A metal-framed dome (generally) is placed over the top of the individual rooms for the ceiling/roof. The front of the house is a wall of glass windows, creating a greenhouse within the house itself. A "bottle brick" wall is what connects the window wall to the tire walls. Bottle bricks are either glass bottles that have been cut, and then two bottle bottoms are sealed together at the open edge, thus creating the "brick"; or they an be plastic bottles filled with earth. These are then placed into a cob wall, or other similar type wall. This makes the building of the wall itself move quicker, and at the same time, if glass, lets extra light into the space in a colorful and creative way. There are so many variations of the design, that you can build just about anything you want. They can be huge, two-story homes, or small and simple. It's all up to you.

The controversial part tends to focus around two key components of the earthship. The first is the use of recycled tires. First off, it is very hard work to do this part of the build. On average, it takes up to about 2 hours per tire, from what I've read. They must be placed perfectly, filled with dirt, pounded, leveled, filled, pounded, leveled, filled, and so on. The tires must be solid and not move at all. It is hard labor, and easily the toughest and most time consuming part of the entire build. But what makes it controversial is the debate over whether or not there is any off-gassing from the tires. There are some studies and experts that say that concealing the tires will cause a build up of gases over time, creating a toxic environment. At the same time, there are just as many studies and experts that say the tires will only off-gas when outside in the elements and exposed to heat and sunlight. But once they are filled and surrounded with earth, that danger no longer exists. So for me, it all comes down to one question: what are you comfortable with? If you are comfortable with using the tires, go right ahead. You can generally find them free or cheap from dumps and landfills, or even offer to take them off the hands of shops that would otherwise have to pay to have them hauled off. They don't have to be in perfect condition. You're not driving on them. They just have to still be together enough that when filled with dirt, they can hold together as a solid wall. If, however, you are not comfortable enough to use the tires, there are other options that can be used. Some, we're going to look it in the coming weeks as independent building styles. Just remember that other things must be considered with some of them. For example, you may need an extra space behind that wall for air to flow as a mold/mildew prevention. Or you may need a layer of insulation between the wall and the moisture barrier. Just a few things to keep in mind.

The other controversial aspect of earthships is the window wall. Now, I've only seen this mentioned in one place, but I think it bears mentioning. If you are building in an area that doesn't deal with snow loads or things of that nature, you may not have to worry about this one. However, there is some concern about snow loads laying on a slanted wall of windows. The heavier the load, the greater the possibility of window cracking/breaking and causing damage to the interior of the home or to anyone unfortunate enough to be standing beneath them when they break. The reason the windows are slanted in the first place is for optimal light/heat into the home (passive solar). Personally, I believe this can be resolved with only a slight slant, if any at all, and make sure that the windows are good quality, and are installed correctly.

Most early earthships were quite the sight to see. Some would even go so far as to call them ugly. There are some that are somewhat less than aesthetically pleasing. However, as the idea has garnered more fans, the designs have become as varied as the people that live in them, This is a bonus, not only with earthships, but with green building in general. They can be completely unique and personalized.

Another bonus of earthships is the design with an interior greenhouse. If you live, or are planning to live in a climate where traditional gardens are not possible for a good portion of the year, this makes it possible. There are some earthships built as far north as Canada which have been known to grow tropical plants within these earthships. According to some sources, just about anything can be grown inside one.

I will say that through all of my research, the basic idea of an earthship is the route I plan to go, only with a few changes and tweaks. I'm also planning on using some cob and earth bag techniques in the design. And maybe a few others. I believe this design would work well with solar, wind, hydro, or especially the plant based energy systems. If you are interested in building one of these unique homes, or just want to learn more about them, I highly recommend the website http://earthship.com/. You can look at floor plans, learn more about the techniques and the man who designed them, schedule a trip to go to New Mexico where they originated to stay in an earthship, learn how to build them hands-on, hire one of their teams to build your earthship for you, and so much more.