& Builders Without Borders
Haiti Relief Fast Facts:
- The Haiti earthquake killed 200,000 and left even more homeless
- Haitians have preferred to build with concrete, but the concrete they make is of poor quality and fails easily
- Haitians have easy access to concrete rubble and native bamboos in the riverbeds, materials ideally suited to building earthen structures to high standards
- EBNet has been asked to show the Haitians how to build new buildings using the plentiful rubble and bamboo, using the EBNet earthen standard as a baseline
- Our goal: to work with local engineers, NGO's and Haitian government to share the standards and get safe housing built quickly and safely
- EBNet was selected as a finalist in the Haitian Government's 'Building Back Better Communities" competition, and has already begun laying the groundwork for building model schools and homes
Now is the time to help
The next step, now that the BBBC program seems to be going forward, is for us to work together with a number of partner NGO's,including Architects Without Borders and Kleiwerks. In addition, we are collaborating with Green Microfinance Global, Ltd.™ on housing and schools with the Peasants Association of Fondwa, Haiti.
Some of the proposed solutions include taking crushed concrete rubble and "reconstituting" into viable concrete blocks. We have already helped purchase a rubble crusher for the purpose, and must now test the new blocks for seismic performance. This reasearch is being done by a team at the Univeristy of Santa Clara.
We need your help now to create a solution that will apply in Haiti today, and around the world tomorrow—the leverage will be enormous. The solutions we put in place in Haiti will be applicable anywhere in the world, for the basic ideas work everywhere. Please send a check or get in touch with us today to find out how you can help.
We hope to raise another $50,000 to help cover the research and put the ideas into action. Checks payable to Ecological Building Network, send to PO Box 6397, San Rafael, CA 94903.
With gratitude and best wishes, Bruce King, Director
bruce@ecobuildnetwork.org
(415) 987-7271
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Mass and Weight are required to tie a building to the earth. Outside forces like wind and earthquakes require a level of mass and weight in order to avoid structural failure. This may be why the old parable about wise people building on a rock is so accurate.
A unified mass like a big rock is a great foundation for building a home, as long as the rock stays together, is heavy enough and is securely anchored to the structure. It would be foolish to attempt to tie a structure to a sandy rock that would crumble at the first strong pull from the anchor.
Because it is not always possible to find a big flat rock to set a house upon, we use concrete to replace the mass and weight of a rock. It is the most cost effective and practical solution to satisfy physics.
In Haiti there is over 20 million cubic feet of rubble on the ground representing the failure of a poorly unified concrete. When the earth began shaking the bad concrete changed from a unified mass and came crumbling down with deadly force. Some may want to place the blame on concrete, but we must still accept the physics that makes concrete the best choice for mass and then understand a little bit of concrete chemistry.
Concrete when done properly results in a product that mimics a solid rock in its mass and weight. The key to proper concrete is found in proper chemistry and the chemistry of concrete requires just three items to create a strong unified mass for a homes foundation.
1. Aggregates (sand and stone) to provide the weight and to create a mass.
2. Portland cement to provide the glue that binds the sand to the stone in unity.
3. Water that chemically reacts with the cement to coat the aggregates so that they harden into a single mass.
This mixture must use proper proportions in order to become hard like a rock and to provide enough mass and weight to resist the wind or the quake. If there is too much sand, you get a sandy mass. Too much water or too little cement powder creates diluted glue, and results in a mass that doesn’t hold together. It was low cement volume and high water content that caused the bad chemistry for concrete in Haiti.
In Haiti the foundations, walls and columns produced from poorly prepared concrete cracked and buckled like a sandcastle, because physics applied more force than the mass could tolerate.
To rebuild a better Haiti will require building on the right side of Physics and Chemistry. It will take millions of cubic feet of concrete to anchor the foundations of the Haitian homes and buildings.
This time we should help them to wisely produce a strong concrete mass. It seems foolish to spend money on any cutting edge or old-school designs without good concrete foundations.