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[tvoivozhd <tvoivozd AT infionline.net>]

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*“Spray-on homes” invented*

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*Technology may help the poor, its developers say*

Posted December 26, 2004
Courtesy Argonne National Laboratory
and World Science staff *
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Researchers say they have found a way to build cheap, sturdy homes in 
one day by spraying a quick-drying ceramic onto flimsy frames. The 
technology could help the world’s poor, of which the United Nations 
estimates there are 1.3 billion, they say.

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Creating a home of Grancrete. (courtesy Argonne National Laboratory)
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*Scientists at Argonne National Laboratory, a U.S. government facility 
in Argonne, Illinois, and Casa Grande LLC, a Mechanicsville, 
Virginia-based company, developed the technology. They say they will 
make it available worldwide after testing whether the homes are 
earthquake and hurricane resistant.

The ceramic is called Grancrete. The researchers say that when sprayed 
onto a crude frame made of Styrofoam, Grancrete dries to form a light, 
hard surface. This creates a dwelling much better than the flimsy 
structures in which many poor people live.

Grancrete is based on an Argonne-developed material called Ceramicrete, 
developed in 1996 to encase nuclear waste, according to Argonne’s 
Explorer Magazine. Ceramicrete thus prevents pollutants from leaking 
into the environment, the magazine reported. Grancrete also netted its 
developers an award from R&D Magazine as one of the “100 most 
technologically significant new products” of 2004.

Casa Grande president Jim Paul told Explorer that his company became 
involved with the technology because initially, it was was looking for a 
concrete substitute for American industry. The need arose because 
concrete erodes in acidic conditions. “But as I traveled in Venezuela, I 
recognized the demand for cheap housing, and I thought about how to use 
our material for that,” he told the magazine.

Paul then collaborated with Argonne’s Arun Wagh to create Grancrete.

Grancrete is stronger than concrete, is fire resistant and withstands 
both tropical and below-freezing temperatures, the developers said; it 
keeps homes in arid regions cool, and those in frigid regions warm.

To build a home, Grancrete is sprayed onto Styrofoam walls, to which it 
adheres and dries, according to the developers. The Styrofoam remains in 
place as an effective insulator, although Wagh suggests simpler walls, 
such as woven fiber mats, also would work well and further reduce the 
raw materials required.

Using Grancrete in developing countries has additional advantages, says 
Wagh.

“When you build houses in these poor villages, the materials you use 
should be indigenous, and the labor should be indigenous,” he told the 
magazine. “Every village has soil and ash, and the labor and training 
requirements are so minimal that two local people can build a house in 
two days.”

Workers only need two days of training to learn how to operate the 
machinery, Paul told the publication. Casa Grande typically assembles a 
team of five people who can start in the morning and create a home that 
residents can move into that evening, he asserted. The material dries in 
minutes, he added, whereas concrete can take hours or days.

Grancrete is made from an environmentally friendly mix of locally 
available chemicals, according to the developers. It consists of sand or 
sandy soil, ash, magnesium oxide and potassium phosphate, which is a 
biodegradable element in fertilizer. So even if Grancrete were to 
decompose, Wagh told the magazine, it would revitalize the soil.

It costs about $6,000 U.S. dollars to build a Grancrete home, Paul told 
Explorer, several times cheaper than a conventionally built home. The 
homes are more than four simple walls, the developers added; for less 
than $10,000 U.S., laborers can produce Grancrete dwellings twice of 800 
square feet, twice the size of a typical apartment in Bombay, India.

Wagh’s said he aims to see Grancrete used throughout his native India 
and the world to produce housing for the poor.

Born in the Indian state of Karnataka, Wagh grew up in a neighborhood 
where even to this day the homes have walls and ceilings made from 
knitted mats of palm leaves, and the floors are made of dried cow dung, 
according to Explorer magazine.

“These homes are regularly subjected to hundreds of inches of monsoon 
rains and cyclone winds and therefore often have to be repaired or even 
entirely rebuilt,” Wagh told the publication. “Obviously such conditions 
can have a great impact on the health, well-being, and longevity of the 
children and adults living there.”

The spray-on cement now offers hundreds of millions of people such as 
these the opportunity to have adequate housing and live longer, 
healthier lives, he told the publication.

Argonne and Casa Grande have extensively tested Grancrete for structural 
properties, post-application behavior and production costs, the 
developers said. Their next step will be to test it for earthquake and 
hurricane resistance, after which they will make the product available 
worldwide. Wagh hopes the United Nations and other international 
organizations will subsidize mass-scale production around the world.*