Precast concrete walls for homes rolled out by Jensen

Sparks-based Jensen Precast, which grew rapidly by providing the most basic of infrastructure for utilities and development projects, is moving upstream.

The company last week began introducing a building system composed of concrete walls, precast at the company's plant at Fairfield, Calif., and installed at construction sites.

The company's pitch to architects and residential developers: While the cost of the precast concrete panels runs about 5 to 10 percent higher than traditional stickbuilt construction, significant energy savings and reduced maintenance will be attractive to homeowners.

Key to the building technology is a plastic connector developed by Dow Chemical and licensed by Jensen Precast for northern Nevada and other markets it serves.

Steve Ruminski, a sales manager for Jensen, explains that the connector ties together the precast walls and insulation typically, a 4-inch concrete interior wall, 2 inches of Styrofoam insulation and 2 inches of concrete exterior wall.

Unlike metal connectors, the Dow Chemical product doesn't conduct heat or cold, a critical consideration for energy-efficient construction.

Jensen uses specialized casting surfaces to create blemish-free precast walls.

The Fairfield plant can produce up to eight panels a day, each of them 14 feet by 40 feet.

Like builders of concrete tilt-up walls, Jensen's crews lay out openings such as windows and doors before they pour the walls.

Because Jensen pours walls within the controlled environment of a plant, it says it can avoid the problems encountered when tilt-up walls are poured at a construction site.

On the other hand, trucking the walls from the plant to a building site adds costs that Jensen executives estimate at no more than $2 a square foot in the finished project.

Some of that cost is offset, however, by the speed of the building system.

Ruminski explains, for instance, that walls can be built at Jensen's plant at the same time that foundations are prepared at the building site.

The time savings, which might amount to 20 to 30 percent on some residential projects, trim financing costs by shortening the length of a construction loan.

Jensen Precast introduced the system to northern California builders and architects last summer.

Since then, Ruminski says, the company has built one home in Sonoma County, is starting a second and has five more in the pipeline.

While the system could be used in commercial construction projects, Ruminski says Jensen Precast has found that much of the early interest has come from folks building upscale homes.

Those buyers, he says, are particularly interested in the long-term energy and maintenance savings.

Launched in 1967, Jensen Precast operates plants in Nevada, California, Arizona and Hawaii.

Its sales are dominated by products such as concrete highway barriers,manholes and drainage structures.