The National Association of Home Builders is planning to construct 70 homes near Bowie starting this year that will be used to test and evaluate new building products, engineering ideas and architectual designs.

Last week, the Prince George's County Planning Board approved the project, called the National Research Test Park, which has been incorporated as a subdivision in its master plan.

The builders' association has been constructing test homes for almost 20 years throughout the country, but decided to consolidate its efforts into the 51-acre subdivision to save money in future land costs, said Kenneth P. Geremia, consultant to the Rockville-based Research Foundation, an association subsidiary that plans and builds the test houses.

He said the foundation will use the subdivision for 20 years, because researchers plan and build only a handful of houses every year. The homes will test new types of insulation, plumbing, energy saving devices, wiring and "products that haven't even been created yet," Geremia said.

The first house to be built on the P.G. site -- dubbed the Smart House -- will be wired into the 21st century with computer consoles and sophisticated electronic temperature and lighting controls. Like many of the foundation's test houses, it is being funded by a consortium of 25 businesses with new products to evaluate.

Manufacturers pay the association to test their products, because they want an independent, nonpartisan evaluation, said David J. MacFayden, executive vice president of the foundation.

"We take their check and are ambivelent about the outcome," he said. "We don't promote their products. If it works, they can promote it with our seal of approval."

However, MacFayden said members of the builders association usually are interested in the test houses, and information about successful products or ideas are passed along to them.

"We do the tests mainly as a service to the building industry and our members," said Michael F. Shibley, a director of the association, who said the foundation also makes a profit from the companies that pay thousands of dollars to have products tested. "Often we run tests -- in energy efficiency, for example -- that may save builders, and therefore homeowners, money," he said.

Shibley said the foundation issues reports on new products or ideas that are available to builders and said builders sometimes tour the test houses as well.

"A smaller builder cannot afford to test, say, a new insulation, on his own," Shibley said. "If it doesn't work, he is in trouble. This way, if it doesn't work, then the builder is safe."

Most of the houses in the subdivision will be sold or rented, Geremia said.

"Sometimes we are finished testing when the house is finished," he said. "Sometimes we monitor it for several years. Sometimes we test by observing how the house is used by its occupants. It really will vary."

The association bought the property some four years ago. Since then, the National Research Test Park has been incorporated into the Prince George's master plan.

Geremia said that plans for the Smart House, the first in the subdivision, are being drawn by representatives of the consortium of companies and that construction is expected to start next winter.