This week: Homes for the eco-conscious

1 Yorkville, Calif. Sedimentary walls add interest to this house of rammed earth, an insulating, low-impact material. The three-bedroom smart home, contoured to the land and its rock outcroppings, features concrete floors; glass walls framing native grasses, flowers, and oaks; a chef’s kitchen; and an entry with reflecting pool and floating steps. The 161.5acre property includes a solar-heated saltwater pool; tiered landscaping; cabin, yurt, and barn with guest suite; and roads, trails, wells, springs, and an independent sustainable power system. $4,100,000. Kevin McDonald, Sotheby’s International Realty–Wine Country–Sonoma Brokerage, (707) 391-3382

2 Westport, Conn. This contemporary six-bedroom home comes with geothermal heating and cooling, triple-paned windows, tankless water heaters, and solar power. The house includes a vaulted skylit living area comprising family room and sunroom with adjoining chef’s kitchen; a two-story library with fireplace; a wine room; a hidden cigar lounge; and a sauna, gym, and yoga studio. The 3-acre wooded property has sweeping lawns and a stone patio with a gunite saltwater pool, spa, and outdoor fireplace. $4,795,000. Cindy Raney, Coldwell Banker Realty, (203) 257-8320

3 Cambridge, Mass. Built in 2019 to LEED Platinum specs, this two-story, four-bedroom townhouse on Observatory Hill exceeds energy-efficiency codes, with electric heat pumps controlling the temperature on separately zoned floors. The home has custom millwork and stonework, herringbone floors, a high-end kitchen with waterfall eat-in island, and a living room with glass French doors to a private garden patio. The building is topped by a 23-foot-long roof deck. $3,400,000. Gail Roberts, Coldwell Banker Realty–Cambridge, (617) 844-2712