Winter visitors to cob buildings often comment on how warm and dry they feel. Cob walls one to two feet thick provide immense thermal mass and adequate insulation, ideal for passive solar construction. Cob structures require little additional heating in winter and remain cool and comfortable on hot summer days. As it is fireproof, cob can be used for building ovens, stoves and chimneys. A favourite design is a cob bench or bed heated by the flue of a wood burning stove.
How fast can I build with cob?
The rate of building depends on weather and the size of your workforce; in dry weather we build up to a foot of height per day. In wood construction, the frame is a tiny part of the work, but a cob wall once built is finished apart from the plaster. Pipes and wires are laid directly in place and there's no need for sheet rock, tape, spackling, sanding, painting, sheathing, or vapor barriers. But racing to build fast is missing the point and half the fun. Unlike conventional modern building with its frenetic pace, power tools, and scope for errors and accidents, cob-making is a peaceful, meditative and rhythmic exercise. Building cob is easier and more enjoyable with a crew, so it lends itself to community projects, building parties and workshops.
What about building codes?
Codes today protect the industrial manufacturers of building components better than homeowners. Not surprisingly, there is no code for cob, though nowhere is earthen building prohibited. Many cob builders choose not to involve building officials and have had no problems. Legally permitted cob buildings are beginning to appear; there's considerable expense and paperwork involved, as with any permit.
What does a cob cottage cost?
Cob is one of the cheapest building materials imaginable. Often the soil removed during site work is enough to build the walls. The owner-builder can supply the labor, inviting friends to join in the excitement of hand sculpting a house. With inventiveness and forethought, the costs of other components (doors, windows, roof, floors, etc.) can be extensively reduced. The Cob Cottage Company works primarily with recycled materials and handwork lumber. Using local materials such as poles, bamboo, stone, and cedar shakes, our second cottage was completed for $500US, and has been lanto Evans’ and Linda Smiley's home for 3 years.
Does cob building require an expert?
Absolutely not! Once the basics are understood, cob building is amazingly simple. In a week long workshop you can learn how to select materials, prepare a mix, and build a wall. You can learn everything you need to build your cob cottage: site selection, foundations, windows and doors, attachment of wood and other materials, detail work and finishing. Many course graduates with no previous building experience leave a weeklong workshop feeling confident and enthusiastic about building their own cob cottage.
How can I learn more about cob?
The only proven way to learn about cob building is to try it. The Cob Cottage Company offers hands-on cob construction workshops in Ireland each year. Contact us for our current schedule. We also supply videos and slides of finished cob buildings . Our web site is www.cobcottage.com. We distribute a practical guide book, The Hand Sculpted House and an informative illustrated reader, Earth Building and the Cob Revival. Our newsletter, the CobWeb. is available by subscription.
The Cob Cottage Company is a member of the Natural Building Network. Find more information about them and other local Irish resources at www.naturalbuildingnetwork.org.