A drafty old summer cottage overlooking the lower East Branch will soon yield to what could be one of the the most energy-efficient, highest tech homes in Westport, following a vote on the matter last week.

Zoning Board of Appeals members last week signed off on a plan from 131 Pettey Lane residents Carmen Legato and Amy Grutzner to tear down the summer cottage they purchased last year, and build a new home for themselves on the property.

“Our plan is, we’re putting our house up for sale this month in Maryland to move here permanently,” Legato, a builder in Bethesda, Md., told board members. “We’ve enjoyed vacationing here for many years.”

The old cottage, which the couple purchased for $625,000 last August, is a drafty, ramshackle structure built in 1937. Like many other modest summer cottages along the coast, it was never meant for year-round habitation — there is no insulation, no drywall, it has a failed cesspool, and “in order to make it a year-round residence that is consistent with modern standards, we need to basically take it down to the foundation,” Legato said.

Though tear-downs are sometimes met with skepticism from approving boards, members of the zoning board, and two neighbors, enthusiastically supported the couple’s request last week. With plans in place, they hope to obtain a building permit soon so they can break down on the project by the beginning of October.

“This is going to be a vast improvement to the neighborhood,” board chairman Roger Menard said.

The house

The new home will be a far cry from the 693-square-foot structure currently on the property. It will cover 2,500 square feet, with two full stories, a garage and a basement, and will rise 33 feet above grade. It will be serviced by a new septic system that employs nitrogen-reducing technology.

Legato, whose Bethesda home remodeling firm specializes in interior and exterior renovations designed to “bring harmony, tranquility and the joy of nature into your home,” said the home will have as small an energy footprint as possible, using the earth, land and water to help heat the home in the winter, cool it in the summer and provide water for the yard.

The couple plan to install four 1,000-gallon cisterns to catch rainwater, with any overflow diverted to an underground “recharge system.” The rest will go to irrigate plants in the yard.

Though it is currently steaming hot in the summer and bitter cold in the winter, the home’s environmental system should reverse that, using in large part geothermal technology.

The couple plan to drill a six-inch hole about 300 to 400 feet deep to access heat year-round, as the underground temperature along much of the length of the hole stays at a constant 45 degrees. That constant heat source will be used to help cool the ambient home temperature in the summer, and heat it in the winter. The heat exchange system will be powered by a solar array that will provide more than enough power to operate the system, Legato said.

In the yard, the couple plan to remove all invasive species and replace them with natives, though they acknowledged that tackling invasives will be a long-term proposition.

Board member Gerry Coutinho recused himself from a vote on the matter, as he owns two properties in the Pettey heights neighborhood. But he spoke on the couple’s behalf as a resident, saying he strongly supports the plan.

So do neighbors Brian and Patricia Tomlinson, of 133 Pettey Lane. In a letter, they wrote that “we have seen their plans (and they) would be a vast improvement and complement the more updated ... homes in Pettey heights, including ours.”

In voting for the couple, Menard said he was impressed at the couple’s plan as well.

“You’re doing a lot of things above and beyond the call of duty,” he said. “All of that (technology), it’s nice to see that people are thinking about that. Because it does make a difference.”

“It’s certainly a nice neighborhood, besides the fact that Gerry (Coutinho) lives there,” he joked.