A 26- floor residential passive house building is currently under construction on New York City’s Roosevelt Island for Cornell Tech’s new campus. This new structureexpected to be completed in 2017- will surpass what is currently the world’s tallest passive house building. It has a height of 82 meters and covers an area of 25084 m2. The exterior walls are 35.6 cm thick prefabricated panels insulated with 27.9 cm of mineral wool and triple glazed windows (U-factor = 0.156). The panelised wall system was chosen both to speed up the construction and decrease the number of joints required to be carefully sealed. Heating and cooling will be provided by variable refrigerant flow air-source heat pumps while a centralised energy-recovery ventilator will provide fresh air to, and exhaust stale air from, each apartment. Panelized wall system The building’s $115 million budget.