Mammoet Uses LTM 11200 Crane to Replace Roof-Mounted Façade Cranes in The Hague

Mammoet, approached by Façade Access Solutions (part of Alimak Group), replaced the roof-mounted Building Maintenance Units (BMUs) on two neighboring Dutch government buildings in The Hague. Each new Manntech BMU comprised sixteen parts—ranging from 200 kg (winches) to 3,500 kg (column and undercarriage)—that required individual lifting. Mammoet worked closely with Façade Access Solutions to determine the safest and most efficient method for removing the old cranes and installing the new ones. Several challenges arose, including extremely limited ground space for assembling and operating a crane capable of performing the job. Mammoet successfully identified the optimum crane and setup position to complete the project safely and with minimal disruption to the seat of Dutch political life.

Determining the Best Crane for the Job

A key aspect of solving this challenge was selecting the right type of crane, as it needed to achieve a lifting height of 180 meters while operating within a very limited street-level space. A crawler crane was initially considered but rejected due to concerns that its counterweight could collide with a nearby viaduct. After further analysis, a mobile crane was chosen—an LTM 11200 (with a maximum load capacity of 1,200 tonnes), fitted with a Y-frame on its main boom for added strength.

Mobilizing this crane—featuring the world’s largest telescopic boom—to the heart of the city was no small feat. The engineering team also determined that there was only one setup location that would allow the crane’s boom to reach both buildings.

“This was due to the Y-frame,” explains Stefan Plugge, Project Manager at Mammoet. “We had to find a position that allowed us to stay clear of the buildings and the viaduct. From the identified position, the crane could service both buildings—avoiding the need to demobilize and relocate it, thereby saving time and minimizing disruption.” During setup, the team used only the space required, further reducing disruption. For the first two days, a smaller assembly area was sufficient. Only on the third day—when the boom had to be assembled on the ground—was the area temporarily expanded. This enabled a key road to be closed for just one day instead of three.

Tall Lifts in a Complex City

The existing façade cranes were dismantled, lifted down, and transported away. The new crane components were then lifted onto the roofs in a specific sequence, allowing simultaneous assembly and further saving time. An adjacent street was used to store old crane sections and served as a laydown area for new components, which were delivered using a self-loading crane.

The team established two lifting zones with defined boundaries: one for smaller parts (up to three meters) and another for larger components measuring up to 10.5 meters in length.

Working within these zones enabled only short-term closures of a nearby canal and adjoining road during the lifting phase. Additional safety measures were strictly implemented.

“We agreed with the client that all items would be attached using fixed lifting points,” adds Plugge. “No items were lifted using slings or alternative methods. We also set a low maximum allowable wind speed for operations.” It was also determined that the roofs were not strong enough to withstand the impact of heavier components in case of a fall. Therefore, a crash deck was installed on each roof before any lifting operations began. As is typical in a governmental hub, The Hague presents a complex environment for high-altitude heavy lifting, requiring detailed permitting, lifting strategies, and safety planning. Mammoet provided all necessary documentation promptly to keep the project on schedule. The team successfully minimized disruption while completing these high lifts safely and efficiently in a challenging urban setting.