Stunning one-of-a-kind Back Bay Penthouse gut renovated in 2015 and designed with an immense attention to detail to meet Passivhaus heating/cooling standards for unmatched style and energy efficiency. This elegant 2 bed/2.5 bath, 1,938 sqft European style duplex features an open-concept main level with living/dining/kitchen area equipped with high-end appliances, custom cabinetry and a large island. Also on this level: a bedroom with ensuite bath, laundry room, and elegant half bath. The upper floor boasts a primary suite with luxurious ensuite and access to two private rooftop terraces with spectacular Boston views. Some of the features include Schüco Aluminium windows, custom closets with push-to-open/handleless throughout, shadow reveals around windows and some walls, Lutron Radio RA2 system and Hunter Douglas blinds. Located on the sunny side of Marlborough St, one off-street parking space included. Close to Newbury St, the Esplanade, and all the Back Bay has to offer. A Must see!