Fortunately, our tryst with cob houses isn’t over by a long stretch. This time around, a Redditor who goes by the screen name of ‘The51stState’ has resourcefully built a 250 sq ft cob hut in the Mendocino County, California, with a budget of just $600.
The low impact nature of the compact cob house started with the construction of the foundation. According to the DIYer, the plinth of the foundation (as seen in the images) is actually urbanite, which was found from pieces of sidewalk from a rock-yard. Underneath this plinth layer, the foundation goes down to a single feet below ground-level, and is housed with the drain pipe layout and then rammed with rocks.
After the completion of the foundation, the designers started out with the above ground-level walls. The majority of these walls were built from cob, an ancient construction material usually composed from a combination of clay, sand, straw, and water. These walls are impressively sturdy enough to mitigate various external forces and pressures, with their apt thicknesses ranging from 10-inches to 25-inches. There is also a separate front wall made from an arrangement of straw bales.
Interestingly, the finishing plaster on the wall surfaces were also concocted in a DIY manner, with filtered clay being mixed with chopped straw pieces and water. And once again in a sustainable manner, all of these clay-based resources were salvaged from deposits lying around the project’s site.
These deftly constructed walls surround a neatly contrived floor, which was made from a combination of sand, clay and water. This composite flooring was dried and then topped with a layer of drain-rock. The internal space was then ingeniously treated with linseed oil and citrus oil, a mixture that substantially hardened the layer and also made it water proof.
Lastly, the building was completed with the arrangement of the roofing assembly. The designers opted for locally sourced pine wood components for the durable frame. The crossbeams were then covered in plywood pieces, which in turn were draped with cardboard components (for better insulation). The entire assembly was finally treated with pond-liner to endow it with water-resistant credentials. And the best part is – the entire DIY dwelling unit is powered by two solar panels and two salvaged car batteries.
Project time – 6 weeks; Cost – $600 (without the solar panels)