A demonstration house under development in Austin will take the progress made in the Green Building Program (see page 19) to the next level. The Center for Maximum Building Technologies has planned a house that will show builders, designers, government regulators, and others how much farther a home can go toward sustainability.
Pliny Fisk is co–director of the Center for Maximum Building Technology, 8604 FM 969, Austin, TX 78724. Center staff distribute an assortment of publications and give lectures and workshops.
A sustainable home is one that is responsive to the natural environment and the human environment. The Texas Advanced Green Builder Demonstration Home, to be built in Austin is designed to be responsive to both.
To accommodate the changing needs of its occupants, the house is designed to either grow or deconstruct over time. Modular components can be added on if, for example, a family expands or adds a home business. Or, the modules can be removed and reused by other similar homes if the inhabitants’ need for space diminishes.
The buildings will have "ribs" that facilitate the adaption of modules, or trellises and greenhouses. The limiting factor to its growth is the solar envelope: growth should not interfere with another home’s solar access.
The Center for Maximum Building Technology, as well as building the demostration home, plans to manufacture and sell the components. All parts will be lightweight enough for three or fewer people to lift, making it a home that a few people could build by themselves.
The homes will be built from abundant indigenous materials such as straw bales; bagasse panels, which are made from a sugar cane byproduct; and caliche, a calcium carbonate widely available in arid parts of the world.
Six different types of hard woods will be used – all are available within 100 miles of the center. Using locally grown wood is preferable because we can assure ourselves that the harvest is being sustainably managed.
The house will also use safe by-products such as wood chips, which will be used as a concrete filler; sulfur as a binding agent; fly ash cement; and certain mine wastes to be used as lightweight aggregates.
The use of massive indigenous materials will produce a constant radiant temperature to minimize heating and cooling loads. A solar dehumidifier will make use of the heat recovery from a solar water heater.
The building’s electricity will be generated by a 1 kW photovoltaic system. A hybrid electric car will act as an auxiliary electric energy source when it is "docked" to the house. The Energy Docking Module capitalizes on the fact that when the car leaves home with people, household energy use drops off; upon their return, energy use goes up. Thus, the total capacity of generators, motors, and batteries can be optimized by integrating functions.
The home will be completely self-sufficient in terms of water. In conjunction with state-of-the-art conservation techniques, water from the building’s roof surfaces will provide all the home’s needs. Landscape plants will aerate and filter the water, prior to its storage in a cistern.
Other plants, including bulb-based flowering plants, will treat the home’s black and gray water. A living fence, made of native woody and thorny plants, and shade plantings near the house will all be supplied with nutrients from the home’s black and gray water systems.
The Advanced Green Builder Demonstration Home is designed to reintegrate the relationship between natural and human-made processes. The design is based on an ecological approach to design: it uses renewable energy, treats wastes as a resource, and makes full use of the other resources found on site, such as rain water and solar energy.