“We are a tribal, egalitarian community focused on living in harmony with the Earth, practicing yoga and meditation, sharing a raw vegan lifestyle, and creating a permaculture farm with lush and abundant food forests in a warm tropical environment.
We are in the process of acquiring a piece of land in the Puna District of the Big Island, Hawai’i, to create a permaculture farm, wellness center and close-knit community of adults and children. This will be a raw-vegan, off-grid community, focusing on simple and synchronized living, yoga & meditation, egalitarianism, permaculture, natural building, beekeeping, natural healing, and personal and planetary transformation.
We are planning to build ‘scoria bag’ roundhouses – circular structures using a variation of the earthbag building technique, as the initial structures to establish and sustain our community and farm. Scoria is another word for volcanic cinder, which is widely available and inexpensive here. This building method comes highly recommended by an earthbag building expert who we are consulting with.
Our main common house and all individual dwellings at Yogi Farm will be similar in design, scaled appropriately depending on need, quick to build, inexpensive, and very attractive and sturdy. This approach is not only simple and elegant, but also in keeping with our egalitarian principles. Our approach is to quickly and easily meet our needs in terms of structures and dwellings, and then bring our full attention to the land, soil, food production, etc., right in the very beginning.
Like earthbag, scoria bag is very quick to construct – actually, even quicker. The main differences with scoria are: 1) it is much more insulative than typical earthbag, 2) there is less thermal mass effect, 3) it is lightweight and easy to work with, and 4) it requires some reinforcing. Hence, scoria bag is a great material, and reinforcing is very straightforward using ‘external pinning’ with rebar [or bamboo], and internal rebar driven through the courses of bags.”
Source: Yogi Farm
Tips for building scoria bag roundhouses in hot, humid climates:
– Using Scoria for Earthbag Building (good overview of the benefits of using scoria or pumice)
– Other reinforcing techniques in addition to external pinning (not all methods are necessary – pick and choose accordingly): earthbag benches, buttresses, bond beam (required), barbed wire between courses, mesh on both sides tied together through the wall, poly strapping, tie courses together with baling twine like Kelly Hart’s dome
– Cooling and ventilation tips: build on high ground with breezes, build in the shade and/or in the forest (but not so many trees that breezes are blocked), cathedral ceilings, wide roof overhang 4’ minimum (minimize direct sunlight on walls), windows on all sides, casement windows aligned to capture prevailing breezes and funnel them through the house, tall windows that go up to the bond beam (no lintels required), air space between the bond beam and roof, screened transom above door, additional plants on the side facing the hot afternoon sun (trellis, more trees, vines). We did all these things and our roundhouse is 8 degrees C (15 F) cooler inside than outside, and the inside temperature stays nearly the same all the time.
– Faster, easier compression ring than the one I used
– Our earthbag roundhouse photos on Picasa
– Free roundhouse Instructable with detailed building instructions
– More earthbag scoria tips at Earthbag Scoria Casita and Festimir’s YouTube Channel