What's Cool In the Pool ... ... And Hot On the Deck

Americans love to overbuild their homes. We put ranges in our kitchens with enough BTUs to light Paris at Christmas, then use them to reheat Domino's. Some even frill up their laundry rooms with stereos and $5,000 mini dry cleaners. So it shouldn't be surprising that rich people are now moving the overdesigning craze outside, to their pools and decks.

Gone are those concrete rectangles plowed into the backyard and surrounded with that plastic patio furniture that sticks to your legs. Instead, homeowners are installing pools with underwater speakers, fire pits — even fake lagoons that emit something the pool industry calls Faux Fog. Small wonder the average cost of new pools has leaped past $30,000.

Those who think of these elaborate pool designs as worthy investments should reconsider. Real estate experts say even the splashiest new pools boost an average home's value by less than 10%. Still, most people who construct waterfalls and poolside theaters are speculating on their dreams, not their finances. It's fine with them if the costs are sunk.