Low-Cost Concrete Homes

Building Poured-Concrete Homes, Journal of Light Construction December 2003, is an interesting article about one contractor's experience constructing cast-in-place concrete houses. Built in Florida, these houses offer termite resistance and hurricane wind resistance appropriate to this area's conditions. Additionally, this system relies on relatively low-skilled workers, making it well suited to that region's building boom economy. A crew of fifty field personnel is able to complete four buildings per day.

A few interesting points:

• Walls are constructed on top of thickened-edge slabs on grade.
• Wall reinforcing is very simple. Vertical #5 bars are tied to reinforcing projecting from the slab at 6-foot intervals. A horizontal #5 bar also runs continuously at the top of the wall. Where door and window openings occur, prefabricated header reinforcing is inserted. Between the vertical bars, 6 foot by 8 foot sheets of welded wire mesh are tied.
• Walls are cast 6 inches thick. One and half to two hours are required to pump the concrete for a typical house. Plasticizers are added to the mix to eliminate the need for concrete vibration during the pour. Forms can be stripped the day after they are poured.
• Interior partitions are most commonly light gauge steel studs, for additional termite resistance.
• Windows and doors are fastened directly to the concrete openings.
• Roofs are conventionally constructed from prefabricated wood trusses.
• The exterior is finished with one coat of stucco (Portland cement plaster) applied directly to the concrete. The interior is finished with 1 inch of rigid foam insulations, strapping, and gypsum drywall.

Overall, the system illustrated is remarkably simple and economical. While these houses won't likely be showing up in the architectural magazines, they are a good study in how to build efficiently and economically.