Thursday, June 10, 2010

Geltaftan - How to set your earth bag dome on fire.

I was just talking to a friend at lunch and he mentioned that he had read about something similar to earth bag domes except that the entire dome was fired and glazed to produce what is essentially a giant clay pot.  While the result is appealing, it seems like it may be a lot more work than I am ready to do at the moment.  Still, something worth thinking about.

I was not able to find much information but it looks like the same guy that pioneered most of the earth bag stuff Nader Khalili is the same guy that is trying to set them on fire.  Below are a few links I found (let me know if there are better ones).


Wednesday, June 9, 2010

Geodesic Dome Introduction

While my primary goal over the next year will be the construction of an earth bag dome, there is another better known design that has been around since about 1926.  This would be the geodesic dome that was popularized by Buckminster Fuller.

As a home I think the earth-bag dome will work best, but the geodesic dome does have a few advantages.  Some of these are as follows:
1. Also inexpensive, can probably be built for under $1000
2. Can be very large.
3. Can be semi-transparent (greenhouse)
4. Are relatively lightweight so can be moved.
5. Can be built quickly.

The structure of interlocking triangles make the geodesic dome the strongest possible structure for the material used.  As a result they are good for large open areas that contain no internal supports.  Apparently Buckminster wanted to put an entire city under one in order to maintain warm temperatures during the winter.  A sphere also provides the most volume with the least surface area, which in theory provides the most efficient use of resources.  This is why they use geodesic domes in places like Antarctica.

In practical terms they do have a few issues.  Using standard building materials (such as wood) they are almost impossible to build.   Every angle is different, there are lots of joins which all have the potential to leak and nothing that you buy at the local home improvement store will fit as there are no flat walls or 90-degree corners.  They also amplify sound so everything inside becomes very noisy.  These issues can be mostly avoided if you buy one as a kit, but then it is very expensive.

However, if you think of it more in terms of a yurt or permanent tent than a traditional house.  Things become much simpler.  Basically you use inexpensive metal galvanized conduit pipe, flatten the ends, drill a hole and join them with a bolt.  Then you cover it with some kind of tarp.  This has been mainly used for making temporary shelters for events such as burning man.

For my purposes I want to build a smallish (25ft diameter) version as a test and to use as a temporary shelter while I build the dome.  Later we may make a guest-house, storage building, or chicken coop out of it.  In any case it will be semi-permanent and will need to be waterproof.  The covering then becomes the most complicated part.  Usually people use a parachute, or make their own cover out of some kind of plastic.  Because of the shape this can be kind of complicated.  There are patterns which can be sown to fit, but this is a lot of work.

My plan (and I don't know if this has been tried) is to cut a cotton or Tyvek drop cloth into circular bands that are cut to fit the contour with a slight overlap on the bottom of each.  Then "paint" over this with polyurethane floor sealer (the clear plastic stuff on gym floors) or fibreglass resin.  Then while it is still sticky throw on some white sand.  The idea is to make the fabric stiff and waterproof and a little heavy so that it does not flap in the wind.

Hopefully if this works out then we can build a much larger version for the aquaponic greenhouse.  In my opinion this would be the most cost effective and practical option but since this part is going to be a community effort I will have to convince everyone else that is involved.  I would estimate that a 70ft diameter dome could be built for less than $2000, which if true would be far less than using a traditional design.

I expect my small 25ft version will be less than $1000 and will be two stories which the top story being a trampoline base.   The reason for this is that I am used to sleeping in hammocks and they are a lot cooler in the summer.  A mattress acts as a huge blanket on one side so air conditioning has to be used to compensate.  A thin fabric does not insulate well so will be much cooler.

Useful Links:

Tuesday, June 8, 2010

Earth Bag Domes Introduction.

FlickrDroid Upload

The motivation behind these things is simple.  No mortgage payments, and very little maintenance.  The entire thing can be built for less than $1000 in materials and a bunch of labor.  The reason the cost is so low is that all you really have to buy is a bunch bags and some barbed wire.  Of course if you are able to spend a little more then it would make the job easier and faster but even then it will still be less than a few thousand dollars.

There is an excellent book with a great deal of information about all aspects of earth-bag construction that is available on Amazon and elsewhere (click on the picture to the left).  If you are actually thinking of doing this then I would recommend buying a copy.

The idea is that you take a woven polypropylene bag like they use for storing feed for farm animals and you fill it with dirt.  If the composition of your particular dirt is too loose then you can buy cheap dirt or stabilize the dirt you have with a little cement or lime.  You then tightly stack the bags in rows and between each row you add a couple of strands of barbed wire to keep it from sliding.  As you go up you move the bags slightly inward until you end up with a dome.  On top of this you put some kind of plaster such as cob, or cement, or lime, or even a living roof of some kind of grass.

filipino.gifThey can be built in a variety of sizes but generally should probably be under 20ft. in diameter.  If a larger area is needed several can be joined together.  Windows and doors are created by stacking the bags into a variety of arch shapes.  Other more traditional structures can be built using the same principal, I am going to probably use earth bags to build a fish-pond for the aquaponics project and for an outdoor hot-tub.

The finished structure weighs about 40 tons or more and is basically impervious to floods, tornadoes, earthquakes, rotting, insects and fire.  The pressure on the bags produces something similar to rammed earth, which has been used all over the world and has held up for hundreds of years.  Most of the great wall of China is rammed earth.  The mass of the structure also helps stabilize the inside temperature.  It takes a long time for heat to pass through and as a result it tends to remain cool through the day and be warmer at night.  If lime is used then it can have a similar effect of the humidity.  They can be built with a sleeping loft in the top and can be partially subterranean for extra thermal stabilization from the earth.

FlickrDroid UploadThe disadvantage is that it is unusual looking, generally smaller than a normal house, and not allowed by most building codes inside city limits.  The lobbyists for the steel and lumber industries pretty much had it written into law that a home had to be "stick built" or metal and generally has to be over a specified square footage.  This is the main reason I had to buy property outside of city limits.  They also require a lot of labor, but I am considering that a free fitness program.

I have a friend that is about half way through building one of these.  He agreed to let me do an article on his dome.  I will try to take some pictures of it for another article in the near future.

Useful Links:
Videos of another couple in Arkansas currently building a dome.

Monday, June 7, 2010

The Property.

So tonight I went and cleared some brush.  I knew I was fat and out-of-shape but dang... Arkansas summers are no fun.  Anyway, I took some pictures to give an idea of what we have to deal with.

The total property that our group purchased is shown.  The green part (1.3 acres) belongs to me and the red (13 acres)  belongs to other people.  It is on a mountain-top but is mostly level and clear.  The wooded part on the right of the first  image is sloped hillside.

The access road is on the left of the first image.  We are going to have to run a road along the treeline at the top.

My part is mostly hillside which is what I wanted.  It has a little bit of level area at the top that includes a very nice large pine tree.

In this first image the top is north.  The plan is to cut a small level spot out for the earth bag dome etc.  I wanted it to be mostly out of view unless someone actually wanted to go down to look at it.

This kind of shows the rest of the hill.  It actually has a pretty nice view to both the east and west.

This is from the edge of the green property above, facing west toward the road.  Eventually we will have to run a road through this.

This is facing south from the same spot.

This is my nice big pine tree.  The lower branches are just above my head and it provides quite a bit of shade.  The hill begins right behind this tree, and the dome will be located through the dark spot just to the left of the tree.

If you walk through that dark spot under the tree you will end up here.  There is a fence that we will have to remove (there used to be horses here).  I have not cleared beyond this point.  But I will take some pictures of the hillside later.

I will try to post some details about the earth bag dome next.

Sunday, June 6, 2010

Something worth blogging about.

I have had this blog sitting here for about three years now. I originally set it up assuming that I was going to make a regular effort to say something profound. After a few failed attempts I finally came to the conclusion that I really was not doing anything interesting enough to bother talking about it. For the past six years all I have really done was work to pay off a large amount of debt. About six months ago I finally did that, and have since been saving money in order to start work on a number of projects that a few slightly strange people may be interested in (thus the blog).

Last week some friends and I purchased 14 acres of land on a hilltop outside of city limits. This will enable us to attempt a number of projects that we have been putting off for lack of time or resources until now. Later some of the other people involved may add their own projects, but for now I will just list the ones I personally intend to work on. Briefly, these are as follows roughly in order of priority:

1. Earth Bag Dome
2. Low cost geodesic dome / greenhouse
3. Aquaponic greenhouse / garden / fish farm.
4. Earth bag hot-tub.
5. Rocket Stove. (to heat greenhouse / dome / hot-tub)
6. Composting water heater (also to heat greenhouse / dome / hot-tub)
7. Mushroom farming (the legal kind)
8. Wood-Gasification / Charcoal Manufacturing.
9. Energy production (solar / wind / woodgas)
10. Possible construction based on polyurethane pour-foam or underground shipping containers.

Information on all the above can easily be found with an internet search, there are videos on you-tube demonstrating most of it. Over the coming weeks I am going to post a brief introduction to each along with some links to external information.

Spending six years doing nothing but paying off debt has convinced me that it is worth going to great lengths to avoid getting in a similar situation again. There are other environmental and philosophical benefits for most of this, and while I consider these to be important, the primary concern for me at least is practical. I want to be free. Free from the stress of having to meet monthly financial quotas, free from the limitations imposed by debt, free to spend what time I have left doing what is really important instead of leashed to the treadmill of american consumerism. But this is another topic entirely that we can argue about in the comments if anyone is interested.

My hope is to live a comfortable debt-free life, that allows for maximum flexibility. If I want to go wander around some foreign-country at some point, I do not want to have to deal with payments, mortgages, utilities, storage etc. I want to be able to just lock the door and leave. I believe this is easily achievable and inexpensive with the most difficult part being a change in mindset and a willingness to consider unfamiliar ideas. I guess we will find out in the next few years.