(Bloomberg News) Some might call it a simpler time. Others might say life was just less comfortable. In 1973, about three people lived in each household in the U.S. The average single-family home built that year was one story, 1,660 sq. ft., and had two or three bedrooms. It was very rare to have more than two bathrooms.

Home life transformed in the following decades: Increased access to financing allowed first-time home buyers to buy larger residences. More homes were built with two stories, and at least four bedrooms and three bathrooms, U.S. Census Bureau data show. Siblings were no longer expected to share bedrooms. Such new amenities as media rooms were added. By 1990 the average American household had shrunk to about 2.6 people, yet the average single-family home built that year was 2,080 sq. ft.-about an extra 400 sq. ft. (just larger than the average U.S. hotel room, which is 325 sq. ft., according to PricewaterhouseCoopers) compared with 1970.

"The standard of living increased, and most households strived very hard to meet that standard," says Stephen Melman, director of economic services at the National Association of Home Builders.

A small percentage of new homes were even larger: By 2000, 66,000 new homes, about 5 percent of homes built that year, measured 4,000 sq. ft. or more, according to Census Bureau data. By 2006 the total more than doubled to 137,000 homes, 8 percent of homes built that year. In 2007 the average size of completed homes peaked at 2,521 sq. ft.

Some cities around the country-many of them wealthy communities-had a greater proliferation of large homes. Data based on home listings in 20,000 Zip Codes and 200 metro areas provided to Businessweek.com by Altos Research, a real-time real estate data company in Mountain View, Calif., show that the median size of homes for sale with a Cherry Hills Village, 80113 address was the largest in the U.S.: 7,654 sq. ft.-more than three times the U.S. median. The listed homes had a median of six bedrooms and seven bathrooms. Other cities that ranked high: exclusive communities such as Rancho Santa Fe, Calif., and Leawood, Kan.

Affluent Denver Suburbs

Cherry Hills Village, an affluent suburb 10 miles south of downtown Denver, has a high median household income of $226,552, according to U.S. Census Bureau estimates. About 40 percent of homes in the city, incorporated in 1945, were built from 1950 to 1969, Census Bureau data show; 86 percent were built from 1950 to 1999.

Most of the largest residences on the market-those bigger than 10,000 sq. ft.-were built in the last decade, according to a search on Zillow.com. The 20,198 sq. ft. home at 7 Cherry Hills Park Drive, for example, was built in 2001, a listing by Kentwood Real Estate broker associate Sandy Weigand indicates. Of course, large homes come with a large price tag: The median list price in the area is $2,395,000.

A suburb just south, Greenwood Village, came in No. 8 in this ranking. Median household income in the city-incorporated in 1950-is $114,460, estimates the Census Bureau. The median size of listed homes in Greenwood Village, 80121 is 5,786 sq. ft., and the median list price is $1,249,000, according to Altos Research.

Greater Pittsburgh: Large Homes Old and New