It really doesn’t look like much, but hempcrete is the green ... building material, it has a history stretching back over 1,500 years. Hemp plaster from the sixth century still lines the walls ...

One of D.C.’s newest trophy office buildings now has the city’s biggest green wall. 17xM, a 334,000-square-foot, 11-story building at 1150 M Street, N.W., includes a two-story, 1,500-square-foot, self ...