All McMansions are not created equal, says Mass Audubon

It truly is amazing what $7.5 million will get you these days in Dover. (Included at that price, of course, are the 17 built-in plasma televisions.)

Between 1999 and 2005, Dover saw the largest new homes constructed of any community in the state, according to a new report by the Massachusetts Audubon Society, or Mass Audubon, New England's largest conservation group. While the average home built during that period was 2,700 square feet, the average Dover home weighed in at a whopping 6,700 square feet.

Of the top 10 towns with the largest new homes, nine were in the suburbs west of Boston. Lincoln, Brookline, Weston, and Carlisle rounded out the top five. Wellesley, which approved tighter reviews of so-called McMansion projects in 2007, ranked eighth, with new homes averaging 4,600 square feet between 1999 and 2005.

Mammoth homes are a problem, according to Mass Audubon's report, because they have an outsized effect on the environment. But here comes the counterintuitive twist: It turns out that constructing a large home in a community like Dover, which is already largely developed, is preferable from an envi ronmental standpoint to gobbling up a smaller tract in more pristine environs, Mass Audubon says. (And, by the way, Dover, unlike some nearby communities, is OK with its mansions.)

"A McMansion in the suburbs is less ecologically damaging than a modest-sized home in the Berkshires," said Jack Clarke, director of public policy and government relations for the Lincoln-based organization.

He explained that's because communities closer to Boston are already built out, or close to it. The habitat for wildlife has already been disrupted, for example.

That's not to say Mass Audubon is promoting large home construction anywhere. But it has to pick its battles, so the group is promoting rezoning and conservation, particularly in the western and southeastern parts of the state, Clarke said.

The news from Mass Audubon comes in the fourth edition of its report "Losing Ground: Beyond the Footprint," a series that began in 1991 and is available online at its website, www.massaudubon.org. A key finding in this edition is the reversal of a long-term trend: Massachusetts is now protecting about twice as much land as it is losing to development, for the first time in decades. Open spaces are being developed at a rate of about 22 acres per day, while about 43 acres are being protected daily, a huge change compared with a decade earlier.

Builder Ron Compagnone is working on two houses in Dover. The larger one, which will be 9,200 square feet when finished and carry a $7.5 million price tag, is set back from Dedham Street. He also just completed an 8,500-square-foot house on Pine Street that is on the market for $3.8 million. Both houses are set on a little more than 5 acres, on what had been empty land.

Of course the economy has slammed the real estate market, but you'd never know it talking to Compagnone. "The higher-end homes, they haven't been hit as bad," he said.

His voice echoes as he gives a tour of the two properties, which he takes great pride in as he points out details, like the lions carved into the walnut mantle of the library in the more expensive home.

For him, environmental issues associated with larger homes, such as increased greenhouse gas emissions or land taken out of its natural state, haven't really come up during his projects.

"No one has really ever mentioned it before," said Compagnone.

But that's partly because those concerns are already being somewhat addressed through zoning, he said.

Dover requires at least 2 acres for a single-family home, and a parcel that size can legally support a house up to about 6,000 square feet, he said. To him that's a relatively small footprint for a lot covering roughly 80,000 square feet.

And Wellesley is no Dover, a distinction that is likely lost on all but the most affluent homebuyers.

Wellesley is filled with half-acre lots, said Compagnone, and when someone tries to build big on such a small lot, that's when the charge of "McMansion" is hurled. Dover doesn't really have that issue because homes are on larger lots, generally away from the street and neighboring homes, he said.

Even as a builder, Compagnone said, he is all for "large house" restrictions - like those in Wellesley, Lincoln, and Weston - that let neighbors have a say when a proposed home goes over a certain threshold.

Unlike those other three upscale towns, Dover hasn't had a debate over restricting home size, suggesting that mansions might just be the norm there.

"I feel like I'm privileged to live in a community with a tremendous amount of open space and good zoning and large lots," said Carol Lisbon, chairwoman of Dover's Board of Selectmen. "I think Dover is a wonderful community, which has managed to keep its open, green character regardless of what the numbers look like."

Last year, Dover put 100 acres of land under conservation restriction, she noted.

Lincoln has had a "big house" bylaw since 2003. It was developed for the same reasons as Wellesley's: "The smaller homes that had been in existence were getting torn down and the McMansions were going up," said Mark Whitehead, Lincoln's town planner.

But here's the multimillion-dollar, meticulously landscaped and marble-tiled question of the day: Are such restrictions working?

"Yes and no," said Whitehead, because the bylaw doesn't restrict the house size, but instead triggers a site plan review.

The Planning Board looks at the overall scale and style of the house and "whether it's overly imposing on the neighborhood," he said.

"They can get them to scale down in certain circumstances, but it doesn't happen too often," said Whitehead. "We're still getting some fairly large homes."

Lisa Kocian can be reached at 508-820-4231 or lkocian@ globe.com.