CEB Vaults
From Abe Connally:
Marcin,
Have you been able to do any research on ferrocement? I found a slightly different way of doing ceilings and roofs that you might be interested in. It is called timbrel vaults or Catalan vaults.
Basically, it consists of creating a vault using tiles, and it requires very little formwork. The tiles then become the form for the roof, so you place your insulation on top of the tile vault, then a ferro-cement cap that could be sprayed on or applied by hand. It removes the need to stucco from below, which is a major pain with ferro-cement ceilings. Also, it reduces the need for steel in the ceiling, which saves a lot on building cost and complexity. You guys could make a tile machine similar to the Liberator CEB press, and use the tiles for the ceiling and the floor, making a building almost completely out of CEB-type material.
We are trying this method out on a small building in the next few weeks, and I will let you know how it goes. The method appears to be very promising, and it would make ferro-cement roofs very easy and fast to do.
Here are some links to look at:
- http://en.wikipedia.org/wiki/Guastavino_tile
- http://www.guastavino.net/
- http://www.lowtechmagazine.com/2008/11/tiles-vaults.html
- http://crossway.tumblr.com/
Good luck, Abe
Comments
(from: Rasmus) There is almost zero experience with using CEBs in Guastavino-type masonry. The unresolved question is whether CEB tiles will deliver adequate structural performance, similar to fired tiles. There certainly is no long-term experience. This can only be addressed with side-by-side comparisons of fired tiles vs. CEB tiles. One example that used pressed tiles is the Mapungubwe National Park Interpretive Centre in South Africa, which won the Holcim Awards in 2008:
- http://web.mit.edu/masonry/projects/projects_mapungubwe.html
- http://www.holcimfoundation.org/T873/A08AMack-gallery.htm
Another option would be to use geopolymer tiles, which would require a relatively low (~450C) kiln temperature and may have structural properties similar to regular fired tiles. But that's really terra incognita.
When building larger communities, the possibility of building standardized components should be considered, such as ceilings and window frames. These can be mass-produced and then transported to the construction site. This would bring down cost and increase workplace safety.
In page 18 of http://www.atdforum.org/journal/pdf/ATDF-Journal-2010-Issue1,2-Architecture-October2010.pdf you can find the image of the manual CEB Tile developed for that African project.
Image1: http://dl.dropbox.com/u/1599184/others/ceb_tile.png
Image2: http://dl.dropbox.com/u/1599184/others/ceb_tile2.png
