The once humble garage has become the latest symbol of competitive affluence in American homeowning. In a generation, the average house size has grown by 50 percent, even as family size dwindled by 20 percent. You can’t find a new home with 1.5 baths anymore; it’s 2.5 heading for 3. Then there’s the kitchen–upscale and eat-in, of course, even though nobody wants to cook. Now the bloat’s moving out the kitchen door and into the garage. In 1989, only 10 percent of American homes boasted three garage spaces or more. By 1998, the number was 16 percent. Gopal Ahluwalia, research director at the National Association of Homebuilders, predicts a sharp rise in 1999 and 2000, especially for four-cars and up.

The first four-car proponents popped up a few years ago in California. But the trend’s gone national, signaling more than family motor pools General Patton might have envied. Most four-car garages won’t actually house four cars. The Alexanders, for instance, plan to keep two cars for now, have a third stall ready when daughters Erica and Erin, 10 and 7, come of age and wall off the fourth bay as an air-conditioned bike workshop. “It’s a form of mass customization,” says George Casey, president of a Florida development company that’s embracing the trend. Orlando architect Don Evans, a grand-garage guru, also preaches flexible space. Your teen-agers are having a party? he asks. “You open the place on Sunday morning and just hose it down.”

Where will this new age lead us? Says Casey: “The only thing I know is in 10 years, we’ll be offering a five-car garage.” Forget the 10 years, and move to Arizona. There, Tucson builder David J. Baird offers five- and six-car options in a new subdivision called Maravilla. “My colleagues told me I was crazy,” says Baird. “I said, ‘There’s a market’.’’ Of the 22 houses he’s sold so far, one buyer opted for six bays, four others for five.

Garage gigantism isn’t just driven by practicalities. Developer Casey thinks living in the world’s most mobile society gives folks an even greater need to hang onto their high-school letter sweaters and grown kids’ highchairs. Former Indianian Bob Hadley and his wife, Marge, agree. Last July they moved to a house near Tampa with a four-car unit–two for cars, one for Christmas decorations, one for other old stuff. “We’re big on Christmas,” says Bob. Researcher Ahluwalia of the Homebuilders Association thinks bragging rights are an issue, too. “You know what happens in this supermaterialistic world,” he says. “If everybody else has a three-car garage, then I have to have a four-car.’’ Garage envy? Who knew?