The incredible, shrinking U.S. house

The single-family home is getting smaller. Three-bathroom houses are on the decline. And most builders think the living room will merge or vanish by the year 2015.

Those were some of the findings shared by the  National Association of Home Builders (NAHB) during the 2011 International Builders' Show, during a seminar called "The New Home in 2015." In one word, homes will be "smaller," according to the survey data.

The average size of a new single-family home completed in 2010 declined from 2,438 square feet to 2,377 square feet. And looking forward, builders are already expecting smaller homes in 2011. 

Smaller homes this year are expected by 52% of builders surveyed, compared to only 7% who expect larger homes in 2011. Lower priced models are also in the pipeline -- 59% of builders will build lower-priced models, compared to 7% who will build high-priced models.

The following expectations for 2015 came from a 2010 builder survey, and are compared to the home of the future survey from 2007. 

• Less than 1,600 sq. ft.: 2%, up from 1% in a 2007 survey;

• 1,600 to 1,999 sq. ft.: 13%, up from 4%;

• 2,000 to 2,399 sq. ft.: 63%, up from 46%;

• 2,400 to 2,999 sq. ft.: 22%, down from 41%;

• 3,000 to 4,999 sq. ft.: 1%;  down from 7%

The NAHB presentation also reported the following:

• Homes with three or more bathrooms declined in 2009 from 28% to 24%. The figure remained at 24% in 2010.

• Homes with three-plus-car garages peaked in 2005, and has been on a downward trend since. These garages are in about 17% of completed homes in 2010.

• More than half -- 52% -- of respondents believe the living room will either vanish or merge with other home spaces by 2015.