The Main Workshop, a historic building dating back to 1957, is a cornerstone of CERN’s technical infrastructure. Covering an area of 5000 m² and housing around 70 operators, technicians and engineers, it will undergo major renovation work starting on 1 October 2025.

The aim of the project, which will take around three and a half years to complete, is to modernise this iconic facility while ensuring continuity of service throughout the works. The renovation will include decontamination, structural renovation, interior refurbishment and modernisation of the heating, ventilation and air conditioning (HVAC) and electrical systems, in accordance with the HPE standard for renovated parts and THPE standards for newly constructed parts. The project also includes the installation of solar panels and rainwater retention systems on the roof, in line with CERN’s environmental objectives.

The work will be carried out in four phases so that normal activities can continue in parallel with the construction operations. Some areas of the Meyrin site, including parking spaces and access roads, will be temporarily occupied by the worksite to guarantee safety and separation between construction zones and areas where work will continue as normal (see sketch).

Beyond technical upgrades, the project has three main objectives:

• to restore high standards of safety, ergonomics, quality and reliability in the workplace;
• to strengthen the integration of the EN-MME teams by bringing them into closer proximity, thereby fostering synergy and consistency in working practices;
• to free up and reallocate 1000 m² of space in Buildings 112, 376 and 18.

The works will affect a large area around the building. In particular, certain roads and parking spaces will be used for the construction site facilities in order to ensure a safe environment and to separate the flow of traffic between the areas under construction and those that will remain operational.

The SCE department thanks the CERN community in advance for its understanding and cooperation while this work is taking place and encourages everyone to comply with the parking regulations. To ensure that the renovation of the Main Workshop progresses smoothly and that its occupants are as comfortable as possible, the Security service will carry out regular checks in this area.