Level 10 Construction, the general contractor for 181 Fremont Street, announced today that it has initiated Phase II of construction with the erection of the tower’s five-story basement. The basement is being constructed with the assistance of a Wolffkran 700 B Luffing tower crane, the first of its kind used in the U.S. The Wolff 700 B crane is known for its ability to move extremely heavy loads at quick line speeds within a tight urban footprint.

The crane will remain on site for about a year. 181 Fremont, an 802-foot-tall, 70-story luxury residential and office tower in the SOMA neighborhood of San Francisco, is set to transform the San Francisco skyline. Designed by Heller Manus Architects and developed by Jay Paul Company, the $540 million tower features a state of-the-art exoskeleton designed in a saw tooth pattern, with a magnificent spire that will ascend from the crown of the building. It includes 435,000 square feet of Class A office space, as well as 67 luxury condos on the top 17 floors. It is pre-certified LEED platinum.

Construction crews have completed deep excavation, shoring and other foundation elements necessary for site preparation. Level 10 has installed a 60-foot-deep base slab to prepare for building out the basement, which is scheduled for completion in three months. Phase III of construction will include going vertical with the structural steel erection of the building. Construction of 181 Fremont is scheduled to be completed in the second quarter of 2016. Project Executive and Manager of Level 10’s San Francisco office, Steve DeWees, said that the tight construction site, which shares a shoring wall with the Transbay Transit Center (TTC), needed a crane that could maneuver easily in a compressed footprint.

“This Luffing tower crane is one of the only cranes made today that has the capacity needed for the size of steel that will be used in the construction of this building,” DeWees said. “We have heavy steel box columns on six corners of the building, and each segment is five inches thick. They are welded to a box and erected one to two floors at a time. Most cranes in the U.S. don’t have the capacity to pick that weight out at the furthest points.”

A Luffing tower crane is a specialty crane that maintains the hook at the same level while the jib moves up and down. The Wolffkran 700 B Luffing tower crane incorporates the latest in crane technology and operator aids, allowing for safer and more efficient construction. It can move over 40,000 pounds in a load with a line speed of 623 feet per minute and has a tower height of 1,000 feet. The crane is manufactured by Wolffkran AG, Germany and is distributed in the U.S. by Maxim Crane Works, L.P