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PROJECT HISTORY Under the sponsorship of the Governor of Baja California, we built a small community of houses and community buildings. The families built their own houses, assisted by students.
The construction system and method were new -- designed an invented by us. We ran a small block-making factory on site, using soil-cement instead of raw concrete for the blocks. The vaults were woven baskets of thin lattice strips, with burlap and chicken wire stapled to them, and the shell of the vault then plastered over the top. Each house was different. It was inherent in the construction process, that a family could lay out their own house, as they wished. We then placed stakes at the corners of all rooms, and the construction system, which included special corner blocks, allowed us to build the columns in the positions marked by stakes, then to build the walls between the columns, then stretch the beams and pour them, and then to weave the vault for each room as it fell out naturally.

People and places in the mexcali community

Javier and Julio -- two lovely men -- the backbone of the families' effort


Inside some of the houses





The beauty of this construction code, is that it does not merely constrain construction (as a normal building code does). Instead it provides the step-by-step instructions for building the building, not unlike the step-by-step instructions for putting up a tent. But the typical instructions for a tent only work when applied to one particular tent design.The purpose of generative construction code goes far beyond this. The remarkable thing about this kind of generative code, is that it does NOT require a prefixed design. As each family lays out their house in chalk -- see picture at the top of this page -- they are then able to generate their house form as they build it, by following the construction steps in order. The result of this procedure is that each house comes out unique, simply as a result of the interaction between the unique house plan, sketched out in chalk on the ground, and the construction operations -- which will then generate a coherent building.


Sequence of Construction Operations
  • 1. Stake out the house with rebars driven into the ground to mark the corners.
  • 2. Place corner rebar-blocks over each corner re-bar.
  • 3. Place a line of bar blocks between each corner and block.
  • 4. Place steel and mesh, then pour the slab.
  • 5. Place corner turret blocks to form corners.
  • 6. Place wall blocks fitting into corner blocks.
  • 7. Locate windows and window sills as the walls are going up.
  • 8. Place a pair of two-by-tens to form perimeter beams.
  • 9. Place reinforcing steel in the beam, place conduit and plumbing lines, and pour the beams.
  • 10. Use the perimeter beams to anchor ends of lattice strips so making it possible to weave baskets for vaults.
  • 11. Once the baskets are woven, fix each crossing of lattice strips with one fine nail to stabilize the flexibility of basket.
  • 12. Staple burlap and chickenwire over basket.
  • 13. Pour a thin, ultra-light-weight frothy concrete to form a one-inch shell (aggregate is perlite and insulation fiber).
  • 14. When the one-inch shell is hard and cured, place a second shell of about three inches in a heavier denser lightweight concrete.
  • 15. Fit window frames and door frames.
  • 16. Using special simple sash construction made out of two-by-two material, build sash and doors to fit the openings.
  • 17. Place finish material on floors.
  • 18. Whitewash the interiors.
  • 19. Complete plumbing and electrical fixtures.

More, and higher-technology versions of this kind of process are needed. It is cheap. It allows houses to be different. It is very sophisticated technically. It requires no drawings.

For further information on the way the unfolding of the building construction actually works, see An excerpt from The Nature of Order, Book 3: Further description of the working of the generative code for the construction of the Mexicali houses and public buildings 5 pages

A more complete description of this generative code for the community in Mexicali, and the buildings there, is given at length in The Production of Houses, by Christopher Alexander, Howard Davis, Julio Martinez, Don Corner, Oxford University Press, 1985   379 pages

established 1967
established 2005

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