Mammoet has completed the replacement of roof-mounted Building Maintenance Units (BMUs) on two Dutch government buildings in The Hague, overcoming complex urban constraints to deliver the project safely and efficiently.
Working with Façade Access Solutions, part of Alimak Group, the project involved lifting and installing multiple components weighing between 200 kg and 3,500 kg. The operation was particularly challenging due to extremely limited space in the city centre and the presence of nearby infrastructure, including a viaduct.
A key factor in the project’s success was the selection of a Liebherr LTM 11200 mobile crane, equipped with a Y-frame for added strength. The crane’s 180-metre lifting capability and compact footprint allowed it to operate from a single position, servicing both buildings without the need for relocation, reducing disruption and saving time.
Careful planning ensured minimal impact on the surrounding area. Road closures were limited to one day, while lifting operations were organised into defined zones to streamline the process. Components were installed in sequence, enabling simultaneous assembly on the rooftops.
Strict safety measures were implemented, including fixed lifting points, low wind speed limits and the installation of crash decks to protect the buildings. Despite the challenges of working in a busy political centre, Mammoet completed the project with minimal disruption, demonstrating its expertise in complex urban lifting operations.
