Two residential developments in Georgia, one with skyline Atlanta views and another in the mountains, demonstrate how builders and architects are continuing to incorporate sustainable features.

472 Martin: The 10 townhomes in this Atlanta community were constructed with light gauge steel framing, which is a unique green element. Marietta-based Metal Benderz digitally designed and built the steel frames before construction began on the three- and four-bedroom units with 2,250 to 2,520 square feet. "There's literally zero waste on site from a framing perspective," said architect Wright Gardner. "It's a very efficient use of materials."

Chaim Frenkel, director of business development at Metal Benderz, said residential homes are typically constructed with wood and commercial properties with steel. Frenkel said the steel frames, which are 100 percent recyclable and made in the United States, are more durable than wood.

“One of our prospective buyers put it really nicely as, ‘Why would you build a home out of lumber or wood, which is like building a home out of firewood, instead of building a home out of indestructible material like steel?’ which is a nonflammable structure that’s going to last for a longer period,” Frenkel said. In addition, steel is also mold and termite resistant.

Construction is expected to be complete in the spring on 472 Martin, which is in the Summerhill neighborhood, south of downtown Atlanta. The developer is Raffles Properties. The builder is Bach Construction. The 10 units, listed in the low- to mid-$300,000s, sold in fall 2015, listed by Tristain O’Donnell of Engel & Volkers Buckhead Atlanta.

Cloudland Station: The This Old House showhome opened in fall 2015 in this 450-acre Chickamauga community nestled alongside Lookout Mountain. The 1,950-square-foot, Craftsman-style home features eco-friendly amenities. For example, Unico equipped the cottage with an energy-efficient heating and air system installed by Rivertech Heating & Air Conditioning in Chattanooga, Tenn. The iSeries units included two high-efficiency outdoor heat pumps, two indoor air handlers, a 4-inch-round flexible duct and 2-inch-round outlets that blend into the architecture.

Scott Intagliata, Unico marketing director, said the system is a third of the size of a traditional heating and air system yet removes 30 percent more moisture. The Unico system costs 25 to 30 percent more than a traditional heating and air system, but the homeowner will spend between 2 percent to 8 percent less annually to heat and cool their home, he said. The small size also helps maintain the architectural integrity of the homes, which range from Colonial style to architecture from the 1940s.

“There is a 20-inch crawl space under the home,” Intagliata said. “No other system could fit in that space.”

Cloudland Station has 15 completed homes and about 55 lots sold, with plans for 300 homes at build out, said John Tatum, CEO of developer Firefly Communities. Most homes range from $400,000-$700,000.