The transformation of the Power Station began in 1995 with the removal of the machinery and a number of out buildings. The building was left as a brick shell supported by a steel skeleton.
The Construction Management method was used to construct the new gallery. The building work was split into distinct packages, each carried out by a specialist contractor. The Construction Manager, Schal (a division of Carillion plc) was responsible for the whole construction programme.
Construction work began on the site during October 2007 when the concrete foundation was laid. At this point, a time capsule containing plans, photographs and videos relating to the project, as well as drawings by local schoolchildren, was buried in the foundations.
A steel framework was built within the existing walls of the Power Station to create the seven gallery floors. This framework also supports the existing brick façade of the building. By autumn 1998, the building was watertight and a detailed fit-out of the space began and by August the following year, the galleries had been fitted out with environmental controls, permanent lighting had been installed across the building and the stairs and escalator had been put in place.
In January 2000, the site was officially handed over to Tate from construction managers, Schal and the installation of the displays began. Tate Modern opened to the public on 12 May 2000.