Ok, with these unorthodox building materials it seems that you learn as you go: The mesh tubing wasn't working out quite the way I'd hoped. The bottles tended to shift inside the tube so that they wouldn't lay flat once they were moved. Also there were substantial gaps in between the top of one bottle and the bottom of the other. I needed something that would insulate better and that was easier to work with and construct. So I thought and experimented, thought some more and experimented some more, and finally I think I have it! The building process is as follows:

1. I created a 4' x 2' 4" wooden frame to keep the bottles aligned while making an insulation panel.
2. I lay a 3' x 8 1/2' sheet of 4 mil plastic sheeting in the bottom of the frame with the overlap hanging out.
3. 66 bottles fit inside the frame and I use spray adhesive to stick them to the bottom plastic as I insert them.
4. Plastic bags are stuffed between any gaps such as the gap around the cap of the bottles
5. The tops of the bottles are sprayed with adhesive and then the sheeting is folded over, sealing the bottles within.

The picture below shows the bottles in the frame.

The resulting panels are uniform, light and easy to handle. They will be tied to the earthbags and then covered with either hardware cloth for plastering or an additional waterproofing layer. I also believe that these panels will be much better at insulating the walls than the mesh bags. Who knows though: I may be changing the plan again!

Well, the school year is finished and therefore so is my collection period for water bottles. By estimation I have approximately 6,000 bottles to show for a little over 2 months. I could never have come close to that number without major assistance from faculty members, parents and students! Thank you all!

As impressive as that number is it is still less than half of what I needed for the original plan. With the 6,000 bottles I had two options (I don't have time for continued collection). I could have covered half the wall in the bottle blocks and used another method for the other half or change the arrangement of the bottles to allow for full coverage with lowered insulation value. As this cabin will mainly be a three season retreat, I opted to reorganize the bottles. I can always add more insulation later if needed.

The new plan is to take the bottles and attach them end to end in long rows. The long rows are fastened together with plastic wrapping and then they are inserted into the same mesh tubing that we will be using to build with (I should have plenty of extra). See the picture below but imagine the bottles in an eight foot tube.

This will considerably reduce the R-value (insulation value) since we are going to be laying the bottles against the side of the wall instead of pointing them out. The insulation thickness goes from 6+ inches of plastic and foam down to about 2.5 inches (the width of a bottle). Oh well.

There are some benefits to this method though. One, the use of the foam is no longer necessary so the cost goes down and the insulation becomes "greener." Two the mesh bags will allow better adherence of the plaster which will eventually cover the walls. All in all I feel very good about what we have done. 6,000 bottles and 18,000+ plastic bags out of the waste stream or without the energy costs of recycling is nothing to sneeze at! Keep checking back to see how things are shaping up.

So we got our estimation back from the first excavation company and unfortunately they quadrupled our projections. I won't post their name but I found their prices beyond reason. The following is what we had required:

1. Clear and level a 50' x 50' area (tearing up stumps and moving to the side of the property)
2. Dig a 2' wide x 2' deep foundation trench in a 100' circumference circle
3. Put in a 10' x 20' gravel driveway.
4. Deliver 40 cubic yards of compactable soil and 18 cubic yards of stone.

As I previously wrote the land is rather sloped and that accounts for some of the cost. Also the delivery of that large an amount of soil and stone requires arrangements to be made for the large trucks to move onto the property. Still the cost of those materials was outrageous. Quality soil is generally around $20 - $30 a yard. Their cost was around $70. Stone is somewhere around $40 a yard around here. Their price was close to $122! We did not deal with this company on burying the rear of the cabin in the slope since this initial estimate came back so high. 

Unfortunately this highlights the cost of doing business in remote areas. There are less qualified companies available for labor and the delivery of common building materials can be expensive or impossible. We have another private contractor to get an estimate from on May 7th. We'll see what happens but since he is an individual rather than a company I expect a much cheaper quote. Also we are going to contract the soil and stone separately from the excavation. I post those results.

I have been playing around with the idea of using hyperadobe building method rather than earthbags for a few months now but I am facing a supply problem. Hyperadobe is a building method that is a relatively recent find by alternative builders. As a constuction method it is similar to earthbags that I have described but the retaining material for the soil is different. Instead of slippery poly bags, hyperadobe uses a strong mesh tubing similar to what is used in produce packaging for onions or potatoes or erosion control booms. The tubing is filled with soil and tamped down solid just like earthbags but each course has greater adhesion to the course below due to the mesh openings. The dirt becomes a monolithic structure and achieves great stability with less effort. The most appropriate tubing material in the US that I have found is called Raschel Mesh or Leno Mesh. The Leno Mesh is pictured above. 

The difficulty I am facing now is where to purchase the materials. Since the material is so thin and lightweight it comes in lengths between 1000' to 3000' which is more than enough to build one cabin of the size that I am planning. However, most manufacturers of these types of tubes will only deal in large quantities like shipping containers or skids. And the few suppliers that I have found are imposing a huge markup on the products. For example, a manufacturer of erosion control booms in Canada lists the product at $300 - $350 per roll, while their supplier wants double that.

If you have any leads on where I might purchase the type of material pictured or listed above please leave me a clue in the comments. Thanks!

Craigslist is my best friend! For the cabin I am attempting to either build or purchase second-hand all of our necessary materials. Again this is making our cabin not only cost efficient but also environmentally sound. It is amazing how many serviceable and good quality items are replaced by homeowners and builders. The saddest part is that these items are often not replaced for lack of functionality but rather for aesthetics. And the aesthetics could conceivably be achieved with just a little elbow grease. The following list details the items that I have already purchased and the price I paid for each:

• 20 small double-hung, double-paned, vinyl windows: $10 each. These windows were picked up from a window dealer as models yet they are fully functional. (There may be a trade off in efficiency versus more modern windows, yet the small size and the other thermal properties of the building help to offset this.)
• 1 Steel Exterior Door: $50.  This door was replaced after a few years of use with a fancier design. It came prehung and predrilled. At this point it needs a coat of paint and a knob/lockset.
• 175 feet of flexible drain pipe: $50. This pipe will be used to construct a french drain at the foundation of our cabin. We needed 150 feet approximately but it is always good to have a little extra. This was purchased from a landscaper that had some left over from a job. New price is usually $1 a foot.
• Bathroom Sink, Base Cabinet, Mirrored Medicine Cabinet: $30. Completely functional and well maintained set. This was purchased from a person "flipping" a house and upgrading the kitchen and bath. It is tiny but perfect for the tiny bathroom that we have planned.