The Elbphilharmonie is a concert hall under construction in the HafenCity quarter of Hamburg, Germany. The new construction sits on top of an old warehouse building (Kaispeicher A) and is designed by Swiss architecture firm Herzog & de Meuron. When completed, it will be the tallest inhabited building of Hamburg, with a final height of . On 2 April 2007, the foundation stone was laid in the warehouse Kaispeicher A, in presence of then First Mayor of Hamburg Ole von Beust, Hochtief Construction AG CEO Henner Mahlstedt, Hochtief project coordinator Hartmut Wegener, Hamburg Minister of Culture Karin von Welck and architect Pierre de Meuron. In 2007, the construction was scheduled to be finished by 2010 with an estimated cost of €241 million. In November 2008, as an endorsement to the original contract, the costs for the project were estimated at €450 million. In August 2012, the cost were re-estimated to be over €500 million, which should also cover the increased cost for a strengthened roof. As of December 2014, construction work is scheduled to end in October 2016 at a cost of €789 million, with an announced opening date of 12 January 2017. The easternmost part of the building will be rented by Westin Hamburg hotel, scheduled to open in October 2016. The upper floors west of the concert hall will accommodate apartments.