Co-operative Insurance Society, or CIS building, is a commercial office in Manchester, UK. The building, completed in 1962, underwent an over-clad in 2006. The facade retrofit included the service tower, which was missing elements, detached parts, and de-colored tiles. A layer of more than 7,000 blue photovoltaic panels were added to the facade, allowing the production of 180 MWh/yr. At the time of the retrofit, CIS Tower had the largest solar facade in Europe.