The project brings together many innovative building concepts and combines them to best meet a given need or situation. The basic principals involved in selection and concept development are:
Detail on the several methods of construction are below.
Air form is inflated over concrete foundation. Foam (EPU) is sprayed 3" on the inside after frames for doors and windows are placed and braced. #4 steel rebar is hung from the insulation 15" OC. vertically and horizontally. 3" of 8,000 psi concrete is sprayed in several passes. The result - a dome, which is the strongest shape covering the largest area per exterior surface. Thermal mass of the concrete combined with the insulation on the outside gives an effective thermal efficiency rating of R-68. An average fluctuation of temperature even in the middle of winter is less than 1/2 degree. Winds, hurricanes, tornadoes with 300 mph winds pass right over with no effect (do cover the windows however). Earth quakes, fire, ice, floods, insects, termites, dry rot have little affect. The main structure can be erected in less than a week.
Post and beam ( 4' OC.), reinforced concrete with 2" skin, both walls and roof, with 10" wall and 12" roof insulation resulting in R values and thermal mass of R-48. Quick and inexpensive to build. Many of the same qualities of a dome as listed above. Look and design of a conventional house. Concrete of 8,000 psi is pumped on the roof and sprayed on the walls. The beams are steel reinforced concrete 6"x 8" configured in a post and beam structure.
This structure uses an EPS permanent concrete form in the shape of 12" x 16"x 48" blocks with posts and beams of concert and steel rebar core to form 6" and 8" reinforced concrete walls with an insulated R rating of 20 to 28 as well as thermal mass. The EPS foam blocks are stacked up on top of each other onto wet concrete footings with rebar placed 4' OC vertically as well as horizontally 32" OC. Concrete of 3,000 psi is pumped into the top of the forms and actually cures to 5,000 psi because the moisture and heat are retained by the insulated blocks. Stucco, brick or siding is placed over the exterior of the block. A conventional roof is applied, or Waffle Crete Panels (forms obtained from a Kansas manufacturer) used for the roof. An 8" to 12" soil and sod covering over this concrete roof is esthetic and environmentally compatible. This construction is very quick and once the foundation footings are poured the walls can be poured in any type of weather even in the middle of winter. (This is also true with the dome described above.) This type of building process is more expensive than the above because of the patents and basic cost of expanded polystyrene.
Another concept involves forms and blocks cast on site or at a factory. These are made of sulfur, an abundant by-product of the oil industry which is inexpensive as a material and is an easy product to produce. The sulfur walls are strong, fire proof, quake resistant, and rot and bug proof. I have a design that incorporates a built-in insulation and thermal break in the block itself. The inside and outside can be finished with a durable, colored, stucco finish made from melted sulfur. As an alternative, a second layer of conventional brick or brick made from sulfur block would be the house's outside finish. A 2" EPS layer of insulation would separate the inner mass wall resulting in insulation and thermal mass combinations approaching dome performance above. This is a more labor intensive process than the dome process or the RM Panel system. However, the process is quicker and less expensive than concrete blocks and over all, fewer steps are in the process. This is a promising technique for certain applications, and is an area of our research for lower cost construction.
There are three methods which use a pre-cast insulated concrete wall detailed below.
A system used for some of the Celistine Property developments involves an earth sheltered concept using rubber tires packed hard (tamped) with earth (dirt) for thermal mass. The 8" concrete pre-cast roofs mentioned above serve as the ceiling and support the earth and natural vegetation. Because most of the materials are natural or recycled, the overall cost is low. However a fair amount of labor is required packing the used tires with dirt and tamping them. The walls are stuccoed. A solarium faces the south for sun, light and growing flowers and vegetables. Add Skywell water systems for water requirements.
For more information e-mail Rock Hard.