Despite the nation's housing slump, Americans love homes.

We love designing them, building them, decorating them, renovating them, expanding them, owning them.

We love showing our homes to other people. We love looking at other people's homes. Given the popularity of HGTV's "House Hunters," we even love looking at other people while they are looking at other people's homes.

Americans also love outdoing their neighbors, which is partly why our houses are getting a lot bigger than they used to be, Newsweek real-estate reporter Daniel McGinn writes in "House Lust: America's Obsession With Our Homes" (Currency Press). He clearly knows his subject, which he covers in a straightforward but entertaining fashion.

McGinn notes how blogs and Web sites such as www.Realtor.com and www.Zillow.com, which offer instant real-estate information, have changed the process of buying homes. Journalists now report on celebrity real-estate transactions, and people talk more about their homes than they used to.

Not long ago, it would have been considered impolite, even vulgar, to ask someone about the cost or the square footage of his or her house. Today, such questions are commonplace at parties and other social gatherings.

McGinn follows a couple from Newton, Mass., as they pump a whopping $360,000 into renovating their house — the same amount that they had paid for it about 10 years earlier.

The author talks to a wealthy shoe company executive who bought a large, expensive house in the Boston area, then tore it down — and built a new, $11 million, 29,000-square-foot residence in its place.

He also interviews house "flippers," who buy cheap property with an eye toward making inexpensive improvements to spruce it up and then quickly "flipping" it, or reselling it for a tidy profit.

Other real-estate investors buy multifamily dwellings, sight unseen, in areas where the cost of living is low and make money by renting out the units for, ideally, more than the cost of the mortgage. McGinn got so caught up in the idea while writing about it that he decided to buy just such an investment property for himself in Pocatello, Idaho.

Size matters in the early 21st century. Garages are enormous, often the largest single space in a modern house. Master bedrooms are commonly twice the size of secondary bedrooms. More people are finishing their basements to add even more living space to their already roomy residences.

Super-sized homes are relatively new in the United States, McGinn said. Houses started becoming bigger partly out of necessity, as free-spending Americans started owning more cars, more clothes and more possessions.

And then there's the keeping-up-with-the-Joneses factor.

The average U.S. home measured 983 square feet in 1950. By 2006, the size of the average newly built house had risen nearly 150 percent to 2,434 square feet. One in 10 homes had three-car garages in the early 1990s; today, that figure is one in five. About 25 percent have three or more bathrooms. Nearly 40 percent have four or more bedrooms.

The only things getting smaller about today's homes are the plots of land on which they are built and the sizes of the families living inside them, McGinn writes.