EllisDon completed the contract for the London City Centre office building, which involved the installation of new sprinkler systems and other upgrades to the fire alarm system in its entirety. The existing fire alarm system covered an area of 700,000 square feet of office, retail, and parking space, remained “live” throughout the upgrading process and was progressively replaced with the new system. Fire sprinklers were installed on thirty-four floors of tenant space, plus mechanical floors. Work also included replacing the main fire pumps and valves; also while ensuring “live” fire protection coverage for the entire duration of the project. Because the 33-year old building is fully occupied, the working hours have been specified by the client between the hours of 10:00 p.m. and 6:00 a.m. inclusively.