Building

Freeform Earthbags Between Boulders

Editor’s Note: The guys are doing some great things on Koh Phangan, Thailand. If you want to take a great PDC course in a great location, be sure to look at this quickly. Their next course starts on March 14, 2011. Find our more here.

This rather luxurious ‘cave’ artfully combines granite, wood and earth. It has a 60 square metre ground floor divided into three rooms on three levels, topped by a 15 square metre loft. While the earthbag walls elegantly fill gaps between large boulders, the double roof structure is elliptic in shape and rests on two sandalwood poles which previously served as main masts on a sailing boat. Corners are entirely absent, and a feeling of peace and tranquility prevails.

After a couple of months of familiarizing ourselves with the subject of earthbag construction, be it by reading books (most notably Kaki Hunter’s and Donald Kiffmeyer’s Earthbag Building) and talking to Owen Geiger on email (big thanks for all the support!), I felt well-prepared and ready to kick off.

Given the somewhat remote location of our jungle hillside property on beautiful Koh Phangan in the southern gulf of Thailand and the difficult access to the building site, many tons of earth were moved manually. We began lowering the ground level between the large boulders which took four guys an entire month. There were many smaller rocks that needed to be rolled out, some of them requiring four people’s attention and energy for a whole afternoon to cover the distance of only a few meters.

In the sections between the large boulders, stone stem walls were built as foundation for the earthbag walls.

Next were the earthbag walls, for which we mixed two different soils (one rich in clay, a beautiful red soil, used here on the island as roadbase, the other sandy in nature). Roughly 25 tons of dirt went into bags in order to form both exterior and interior dividing walls. Sticking to the principles of organic shapes and free-form construction, a point was made in avoiding corners which tend to trap energies, on a subtle level. We used cheap and readily available cement rings (used for wells) for windows and ‘doors’, and later simply covered them with a sturdy, high-grade mosquito screen, which went in before the render stage. Keeping the building open as much as possible was of primary importance in order to allow the breeze to flow freely through the structure at all times.

We then erected the two main poles, and began working on the intricate roof. I worked with five local carpenters for six weeks to finish both the roof and the interior loft. Seven cubic meters of a regional soft wood called “takien ra” were used to build it all. The massive rafters (2” x 6”) were spaced at only 50cm from each other, for entirely aesthetic and not structural reasons. The roof is covered with very light ‘jaak nam’, a local palm thatch with an expected life expectancy of 4-6 years. Contrary to what some people think and write, such an organic roof is 100% waterproof. Once the tiles ‘expire’, they are taken down (1 day of work) and replaced with new tiles (3 days of work).

We next rendered the earthbag walls, using a mixture of beautifully yellow soil (55%), coarse sand (30%), white cement (15%), plus some yellow and red iron oxide. In order to avoid metal (for energetic reasons), we resorted to nylon fishing net for extra render support instead of the frequently used varieties of chicken wire. Ideally the plaster on an earth wall would not contain cement at all, but given the absence of both local clay and a fibrous material such as straw, adding a bit of cement to stabilize the earth seemed the best course of action. Great importance was given to long eaves all around the house, for a dual reason: 1) to protect the walls at all times from direct exposure to sun (massive earth walls such as earthbag walls store both cold and heat very well, and in a tropical climate such as ours one wants to have a pleasantly cool house at all times), 2) to protect the render from the heavy rains, particularly during the monsoon months. For the interior stucco, only white cement and fine sand were used.

The floors have either a gravel or stone base to prevent water from coming up from the ground. We either did a couple of layers of pure roadbase earth, or a mix of regular portland cement (8%) mixed with coarse sand (16%), gravel (38%) and a very generous amount of soil (38%) to stretch the mix and economize on materials. The top coat is white cement (30%) and fine sand (70%) plus yellow iron oxide.

The whole structure cost about $21,000 USD, including a simple 300 Watt solar system to power lights and this laptop, as well as an outdoor kitchen which was added in June 2010.

The house ‘performs’ well, meaning it is pleasantly cool even at midday when outdoor air temperatures are noticeably higher than indoors.

7 Comments

  1. I love your THICK WALLS: https://vasarhelyi.eu/books/A_pattern_language_book/apl197/apl197.htm

    Are your cement rings used for window openings splayed at about 50 to 60 degrees to the plane of the window, so that the gentle gradient of daylight gives a smooth transition between the light of the window and the dark of the inner wall? See: https://vasarhelyi.eu/books/A_pattern_language_book/apl223/apl223.htm

    To add some cement in the plaster for the outside wall is no problem in Thailand, as the moisture always move from the warm to the cold side. To do this in a cold climate should be hazardous, as the moisture here moves the opposite way, and the plaster should soon loosen from the wall.

  2. I read through your story and now I’m wondering why it is in this site. Is this considered permaculture in any aspect? I don’t see the connection between the principals of permaculture as applied to the built environment with this extremely elitist dwelling you constructed for yourself out of virgin wood and with walls constructed with 15% cement, which is typical of the weight percent in most concrete structures. Is it beautiful and clever? Yes. Is it permaculture to spend weeks hollowing out a space between boulders to make an art project? The projects we undertake at this point in our collective history are really important, especially when we place ourselves in the midst of a different culture. Maybe I’m alone in feeling disappointed by this entry.

  3. I have enjoyed the above stories about building and found them very interesting ,inspiring and educational. Meeting onsite needs with as much onsite/neighbourhood materials and labour as possible . They look like examples of practical permaculture design.I am thinking how usefull would be the work F Schumacher, Small is Beautiful, appropriate /intermmediate building technology.Seems to be forgotten and or overlooked these days.

  4. Really impressive and inspiring. For me, the attraction of building my own home is the ability to CREATE something. @Donald, permacutlure has no dogmas, its about being considerate, considerate of both people and the environment. I mean, just look at those interior rocks, is that or is that not a celebration of being human, of this earth, which, by the by, is the derivative of the word ‘human’. And ‘humus’ but i digress.

Leave a Reply

Your email address will not be published. Required fields are marked *

Related Articles

Back to top button
Close