Four years ago, Heather was a recent college graduate working full-time at Ferrier Custom Homes, her father's company, and daydreaming about buying her own house. Around that time, her father, Don Ferrier, got hooked on the idea of building a home that would be not only entirely "green" but also affordable for the average American family.

Heather was game to be his guinea pig: As a child, she'd struggled with asthma and allergies and understood how a home could affect one's well-being; now a vegetarian and a "conscious consumer," she says she's always "looking for ways to tread more lightly on the planet." So the Ferriers hired Dallas-based architect Gary Gene Olp to design a home that would be, according to Olp, "contemporary, easy-to-build, highly energy-efficient, and lovely." The biggest challenge was to accommodate Heather's construction budget of $115 per square foot, a pea-size figure compared to other green homes.

Every design decision was made with both budget and earth-friendliness in mind. Sculptural glass blocks allow ample sunlight into Heather's living room, which reduces the need for lamps and fixtures. When she must have artificial light, Heather uses energy-saving compact fluorescent bulbs.