By Aglaia Pikounis and Jeff Haynes

Going small is big.

The average size of single-family homes traded so far this year is the smallest it has been in two decades. Massachusetts' peak size came 12 years ago when the average square footage for homes sold was 1,870. This year the average size is 1,783 square feet. The last time it was lower was in 1987 when the average size was 1,778 square feet.

Some experts say foreclosures are not only dragging prices down but could be affecting the size statistics as well.

"The homes that are selling now are heavily dominated by foreclosures, and financially distressed properties tend to be smaller," said Kermit Baker, a researcher with Harvard University's Joint Center for Housing Studies and chief economist for the American Institute of Architects. "That's distorting a lot of the sales information that we're seeing right now."

Home size trends are generally more pronounced in new construction. Nationally, newly built homes have gotten larger over the years. But there appears to be some movement toward smaller residences within the building industry.

The average size of newly built homes in the Northeast was 2,582 square feet in 2007, down from 2,610 in 2004, according to the National Association of Home Builders. Even though properties in the Northeast remain larger than the national average of 2,479 square feet, builders in this region have scaled back a little in the past couple years while the national trend has steadily ticked upward.

Architects are also reporting that home sizes are shrinking.

In the most recent quarterly design trends survey by the American Institute of Architects, 33.5 percent of the respondents noted home size declines, while 15.5 percent reported increases. Just two years earlier, the responses were different, with twice as many residential architects saying homes sizes were on the rise versus those who said sizes were decreasing.

"The question there is how much of this is a cyclical phenomenon - the economy is in bad shape so households might not be looking to buy a lot bigger homes - or how much of it is a secular trend" where buyers are seeking smaller, better designed homes, Baker said.

Minneapolis architect and author Sarah Susanka has embraced and promoted quality over quantity in residential design.

Her book, "The Not So Big House: A Blueprint for the Way We Really Live," highlights the differences between expansive homes with non-functional and rarely used spaces, and well-designed homes with less square footage.

"I think that [those books] have been received very positively in the marketplace. I think people are interested in looking in the direction of doing more with the space they have," Diane Georgopulos, president of the Boston Society of Architects.

Function Over Size Susan Renfrew, a Greenfield broker who is president of the Massachusetts Association of Realtors, said buyers rarely come to her with a particular home size in mind.

"I'm not hearing anyone come in and say I want a smaller home or 1,500 square feet. They never talk about square footage. They talk more about function and things like the number of bedrooms," she said.

Once they start looking at homes they then get a better idea of how much space they need, she said.

With surging oil and gas prices, more buyers are concerned about energy efficiency. "That may play a role in the square footage because people are thinking about how much house they want to heat," Renfrew said.