See more photos in the gallery below.

With its farmhouse shape, Tony and Janet Lewandowski’s nearly finished new home in La Grange fits well among the traditionally styled homes on the block. But it differs from the old-timers in a significant way: designed to be miserly with natural resources, the house aims to be the first in La Grange to get LEED certification.

The Lewandowskis have renovated or built four houses in the past dozen or so years. None was an ostentatious McMansion, but even so, this latest is an intentional step down—in resource use, size. and cost.

Janet survived breast cancer, and Tony, an architect, worked for a while in Masdar City, a green development in Abu Dhabi. Both experiences led them to reassess “what we are leaving for our children,” Janet says, which is why they decided to build this house sustainably. It’s supertight to keep heating and cooling costs down, its materials have a high proportion of recycled content, and its paints and finishes have low or no VOCs. It’s also financially sustainable. The Lewandowskis saved money upfront by buying a foreclosed home, and they will save going forward because of the new home’s low energy bills.

For more on the project, click through the tour below, or read the Lewandowskis’ blog.