The site of the People's Co-op expansion on 21st and Tibbets SE was abuzz with activity on Sunday afternoon. The sun shone down on a dozen volunteeers working on the cob walls of the new building. Cob is made of clay, sand, and straw and is kneaded like bread dough into a thick consistency that can be shaped while wet, but that dries solid and brick-like.
Cob is a hands-on medium, and the volunteers were happily smeared with mud on this perfect day. The cob wall taking shape on the building's east side will be fire-proof, earthquake resistant, and an excellent insulator to boot. This natural building substance is affordable, but also practical and durable. Cob houses in the British Isles have lasted for hundreds of years. Once started, the process of creating a cob structure must be followed through to completion within a reasonable amount of time so tht the entire thing dries at once without seams. The result, if successful, is one big solid chunk of cob.
Cob isn't the only groovy aspect of the expansion and renovation of People's. A resevoir has been buried under the property to collect rainwater, which will be used with the building's toilets. A heat exchange system for warming in the winter and cooling in the summer has been built by putting a pipe with a coil 300 feet into the ground underneath. It is the first of its kind in Oregon. The upstairs of the new structure will have a beautiful community room with high ceilings.
Work on the cob portions of the new People's structure needs to be done by the end of May so that the cob can have enough time to cure by the scheduled grand opening in September. Volunteers are always welcome and can come on any Saturday or Sunday in May, starting as early as 9:00 a.m.
Other opportunities to learn about cob and other environmentally friendly technologies will be available during the Natural Building Convergence (NBC) in May. The five completed projects in SE Portland will showcase the aesthetic, environmental, and economic benefits of building with natural and reused materials. All ages are welcome but NBC requests pre-registration.