The roof is also constructed of foam panels that are held in place by aluminum channels. Once covered with Grancrete®, the roof becomes an integral, water-tight part of the home.
Groovy Green has a story about Grancrete® — a very easy and affordable alternative to concrete that should help people without homes in many parts of the world quickly develop a living space of their own.
Stronger and harder than concrete, this building material means that a builder can erect a house in a matter of hours. Groovy Green suggests first constructing the frame, applying structural insulated panels (Styrofoam or naturally insulating material), then coating the outside with Grancrete®. This sprayable ceramic is cheap, fire-resistant and a good insulator in cold and hot climates.
The Office of Technology Transfer has more information about various coatings that have resulted from recent material science research. The website includes a PDF document and movie showing the rapid assembly of a “pre-fab” building Grancrete® Spray-On Structural Cement and Rapid Construction Process for Low-Cost Housing.
Prefab housing is not new – in fact, simply having components that are manufactured in off-site industrial facilities constitutes the basic definition of prefab, and has been a part of home construction for decades. WorldChanging – “Fabulous Pre-Fab“
Groovy Green probably saw the story about Grancrete written by Jill Fehrenbacher and Sarah Rich of Inhabitant. They also have a story about modern cabins that can be prefabricated, delivered, and erected in 10 days. Besides pre-fabrication and modular design, a way to reduce the cost of building a good new home is to make it more compact. Another example of quick shelter is Modern shed, which can be assembled over a weekend. Still for quick-to-assemble, how about a multi-purpose cabin that can be assembled in four hours and disassembled in one hour. Treehugger tells us that German designer Frank Thoma drew inspiration from traditional Balinese architecture to design his portable, configurable housing.
Prefabricated, modular homes are just part of the story. Architectural features also include energy efficiency, low cost and less of an environmental “footprint”.
In partnership with the Piedmont Housing Alliance in Charlottesville, VA, students at the UVA School of Architecture intend to design and erect at least three 1,000 – 1,2000-sq.ft. homes in low-income communities in the Piedmont area in phases over the next four years.
These are not your standard affordable houses. The ecoMOD homes are modular and eco-friendly, with emphasis placed on marrying indoor and outdoor space through passive design strategies.
Note: As Mother Earth News related, even Habitat for Humanity is going “green”.
Ventilation, and in particular, the control of humidity is one of the problems associated with a a super-tight, super-insulated, green building, such as the pre-fabricated, modular, quick-to-assemble, ceramic-coated Styrofoam shelter developed by the material science group at the Argonne National Laboratory. Michael McDonough, AIA, NCARB has specialized in sustainable practices architecture for more than 20 years, and coauthored? The Smart House. He took special care with vapor diffusion in his eHouse, a model home in the Hudson River Valley of New York:
Moisture in the building? water vapor, is controlled through carefully engineered sequences of materials acting as vapor diffusion resisters (in industry parlance, VDRs). This means that the interior finishes, the core materials of the walls (SafeCrete autoclaved aerated concrete and Winterpanel structural insulated panels), exterior finishes, the insulation in the roofs (Applegate recycled aper cellulose), and even the roof assembly all are designed to complement each other, and to allow the buildng envelope to move moisture out of the core to the dry side of the wall.
Good Green Homes ASIN: 1586851799
Good House, Cheap House ASIN: 1561587524
Compact Houses: Architecture for the Environment ASIN: 0789313499
Compact Houses ASIN: 849626310X