The latest sign that Chicago’s building freeze is beginning to thaw is a nearly 50-story, crystalline residential tower planned for River North. Designed by Brinistool, Kerwin, and Lynch (BKL), the minimalist tower will feature smooth glass facades on the east and west sides, and deep balconies—flush with the building—on the north and south sides. “The building continues the Wacker Drive streetwall, so it’s a very visible face of Lakeshore East,” said Thomas Kerwin, a principal at BKL. The six-foot deep balconies will have glass balustrades and run the entire length of the rental apartments. The all glass sides feature tinted and fritted glass—the frit will mask the structure behind—creating nearly seamless-looking facades. The approximately 650,000- square-foot, 500-unit building will also have a planted roof and, atop a retail base, a pool.