Trish Kelly and John Kellenberg never intended to build a house. A great location and a roof-destroying blizzard changed their minds, however, and now not only are they building, but they’re committed to constructing a sustainable, healthy house that’s on track to be LEED certified.

“We really liked our neighborhood, but there was very little on the market here,” explains John of the family’s search for a new home that could accommodate their growing kids and desire for more stay-at-home space. “We had the house for sale when the blizzard hit, and it did quite a bit of damage, so we quickly changed course and decided to build on our site.”

Though tearing down their Chevy Chase, Md., rambler was a different course than they’d planned, rebuilding to eco-friendly standards was a no-brainer for a family already devoted to living efficiently and sustainably. John bikes to his job researching environmental and natural resource management issues with a focus on climate change. That work took the family to Latin America for six years, where they experienced the benefits and pleasure of buying local, having a house attuned to prevailing breezes and solar orientation, and stronger bonds resulting from living in open, flexible spaces. The kids, now 13 and 11, also are on board with building a house that won’t harm the environment and will last for generations.

John recognized the need for sustainable long-lasting materials and environmentally friendly construction, but he credits Trish for pushing the energy-efficient, healthy-home agenda. After interviewing several builders, Bethesda Bungalows stood out. Trish was frustrated that most pros wanted to build to the lot lines despite the family’s request for a reasonable footprint.

“Peter [Guida] listened to us,” says Trish, of Bethesda Bungulows’ owner. “He wanted to build something … that’s still bigger than anything we’ve ever lived in, but he’s devoted to energy efficiency and green aspects.”

To save money on design costs, the Kellenbergs chose to modify an existing Bethesda Bungalow plan called the Incredibly Green House. They relied on the builder for guidance to stay on a tight budget while maintaining sustainability and incorporating desired details.

“We’re real people on a really tight budget,” explains John. “We are a new clientele for Bethesda Bungalows, but they were excited to take on the challenge.” Although the estimated cost of the project grew to $750,000 for the 3,800-square-foot house, building a new house—let alone a sustainable one—for less than $200 a square foot is a tight budget in the Washington, D.C. area.