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Dear all,
I'm close to done with the cob-core building proposal; my recommendation over SB, earthships, superadobe, bamboo huts etc. Please feel free to use it in anyway you may see fit if you're involved in relief work. (And I'd appreciate suggestions for improvements.) I'll gradually fill in the blanks in the budget, and adjust if I've made any mistakes. Apart from that I'm off Haiti, devoting my spring to more local issues...such as finalizing our straw bale house and co-facilitating our internships. This is the first introduction. Please enjoy the full text with numerous links and illustrations on: http://nbnetwork.org/nb/haiticob Max Vittrup Jensen Director, Events and Marketing Natural Building Network Important Disclaimer: NBN is only a network. Our role in this plan has been to connect the people with expertise in Natural Building, as well as advice an effective approach in view of the local available local material, economy, climate challenges and historical/cultural preferences of Haitians. These parameters has eliminated a series of more exotic building designs and techniques. NBN does not have the funding and resources to proceed with implementation of the plan, this is up to whoever wants to make use of it. The plan is written in a pro-active tone by Max Vittrup Jensen, (NBN board member), enabling it to be downloaded and used for submission. Please do not interpret this as if the project is already being implemented. It is important to emphasize that this is a plan open for everyone to adapt and use, just make sure youâll contact the relevant experts/sub contractors if you plan to include them in your application. ââââ00O00ââââ The aim of this project is to construct 4000 simple 4Ã5 meter earthquake proven (9+) core-shelters out of bamboo re-enforced cob, which residents easily can expand into family houses in the future. Our emphasis is to work with future residents in design of their community and structures: The process is based on training Haitian low-income owner-builder teams, whoâll afterward be in charge of small mobile commercial equipment, establishing local skills and enterprises. We outline how three sustainable micro-businesses will be established as part of the process. A central element in organizing the community is a planning process with future inhabitants, facilitated by experienced experts in permaculture and urban design. This process will result in sustainable neighborhood groups, which commits to jointly build a cluster of dwellings; approximately 10-20 families per group. Key features of the project will be enhancement of community facilities, rainwater catchments, local waste-water treatment, and garden allotments. We will then construct 10â x 16â Core homes that are earthquake proven (9+). They will be built out of bamboo re-enforced cob (a mixture of earth and straw), which residents easily can expand into family houses in the future. Building together with both Haitians and international volunteers, after an extensive training and guidance the foreign builders will gradually withdraw to an advisory role, while repeating the process for other groups. Our aim is to build structures which residents easily can expand into family houses in the future. The process is based on importing simple mobile earth and straw mixing machines from Czech Republic, in order to expedite the building process. Image of cob shed in Oregon; thicker walls and different roof. This is without bamboo re-enforcement. Click here for quake test of such structure Addressing the Challenge: Cob Core Housing Requirements Thanks to extensive networking contacts and reports from Haiti relief workers, along with the recommendation from the Haiti UN housing Cluster, it has been concluded that addressing the housing shortage in Haiti for the short-term means having a solution that meets the following key requirements:  * Feeling of safety and comfort for inhabitants relative to seismic activity  * Hurricane-ready  * Heat and flood management  * Durability  * High effectiveness in construction; utilize simple tools and trained teams of assembly technicians working with untrained local labor  * Scalable production  * Low cost  * Low environmental impact The cob-core units presents a solution to all of those challenges, while predominantly utilizing local materials, and allowing for future expansion of the units. The use of Earthen construction allows for inclusion of minimum trained labor of all genders and ages. It serve to regulate the interior heat, and is freely available. Apparently Haitians are not very likely to adapt to non-traditional shapes of housing, and hence our model is proposed as a simple rectangle with a sloped roof: In due time other rooms can be attached and the roof become a saddle roof. Earthen construction is usual in Haiti as in the wattle and daub technique; Our technique is somewhat the same, however further improved for seismic activity and floods: We make a foundation out of old chunks of concrete, secure plastic ties under the concrete which gets embedded in the walls and are used to tie the light-weight bamboo roof construction to the foundation. The four wall sections are made of split bamboo woven into a 6 inch grid, and with diagonal split bamboo included, in effect making a hexagon pattern in the grid. This techniques was developed by J. Becker during relief work in Banda Aceh, Indonesia. The cob machines are specially designed to fast and effectively mix earth with long fibers, while remaining of a quite simple and sturdy mobile design. The cob mixture is applied from both sides in about 4 inch thickness, while making sure that the long fibres (straw or local grasses) are inserted through the holes of the bamboo grid into the mixture on the other side. This way the cob core in effect becomes a monolithic structure, which (once dry) is virtually non-destructible. As bamboo is a grass, and the split pieces treated by boiling and kiln dried, they are of no interest to termites. Despite the high humidity the cob walls will dry relatively fast due to breeze and the high average temperatures. Both the external sides of the structure will get a lime plaster, which prevents damage from driving rain. The resulting structure is more sturdy than the phase 2 structures proposed by the Haiti UN housing Cluster, hence resisting hurricanes better, yet there is very limited possibility of the roof or walls doing any harm to the inhabitants, should an extreme magnitude earthquake manage to damage the walls or roof. The light weight concrete roof tiles represent a much lower degree of embodied energy and cost, than the typical corrugated metal roofs, it does not transfer heat to the interior in same way as metal, and it dulls the sound of the torrential rainfall, while allowing for suitable clean water to be captured and reused. |