The CIS Tower building, headquarters of the Cooperative Insurance Society Manchester England UK

The CIS Tower is an office skyscraper on Miller Street in Manchester, England. It was completed in 1962 and rises to 387 feet (118 m) in height. The Grade II listed building, which houses the Co-operative Banking Group, is Manchester's second-tallest building and the tallest office building outside London. The tower remained as built for over 40 years until maintenance issues on the service tower required an extensive renovation which included covering its facade in photovoltaic panels. The tower's design was influenced by Skidmore Owings & Merrill's Inland Steel Building in Chicago after a visit by the architects in 1958. Interiors were designed by Misha Black of the Design Research Unit. Renovation Within six months of construction some of the mosaic tiles on the service tower became detached owing to cement failure and lack of expansion joints in the concrete. Although the tower was granted listed building status in 1995, falling tiles were an ongoing problem. English Heritage had to be consulted as alterations could change the building's appearance. In 2004 CIS consulted Solarcentury with a view to replacing the deteriorating mosaic with 575.5kW of blue building-integrated photovoltaic (PV) cells which would provide a permanent green energy solution, generating approximately 180, 000 kWh of electricity per year. The work was completed by Arup and at that time was the largest commercial solar façade in Europe. The PV cells made by Sharp Electronics began feeding electricity to the National Grid in November 2005. The project, which cost £5.5 million, was partly funded by the Northwest Regional Development Agency which granted £885, 000 and the Energy Savings Trust at the Department of Trade and Industry (DTI) contributed £175, 000. The solar power project was chosen by the DTI as one of the "10 best green energy projects" of 2005. Out of sight on the roof are 24 wind turbines generating 10% of the tower's electricity