Vacuum Lifting Technology Lands on White House Steps
National Park Service (NPS) cites safety and versatility among major considerations when deciding on concrete lifting system manufactured by Tulsa-based Vacuworx to handle recent renovation of South Portico stairways at the White House, in Washington, DC.
Vacuum lifting technology has made its way to the White House as part of the National Park Service’s historic renovation of the building’s South Portico steps. The US$1 million ($1,28 million) project, which included dismantling Truman-era staircases and installing carefully selected cuts of Missouri limestone, was completed between August 5 and August 30, 2017.
Jessica Gordon, an exhibits specialist with NPS’ Historic Preservation Training Center (HPTC), said a material handling solution that incorporated a Vacuworx MC Series Vacuum Lifting System proved advantageous as crews pulled 2 base stones weighing approximately 1,100 kg each, and set a total of 46 new slabs. Each new South Portico step – there are 21 located on the east and 21 on the west – are approximately 25 cm long, 18 cm deep and 50 cm wide. The 4 new landing stones are 335 cm long, 18 cm thick and 183 cm wide. Ms. Gordon worked directly with Vacuworx to rent a MC 5 lifter and 3 custom pad assemblies. The carrier equipment was rented from Extreme Steel & Rigging, based in Warrenton, Virginia.
The MC 5 operates using a self-contained diesel engine. When activated, the system pulls a vacuum between the pad and object to be lifted, providing a powerful positive seal. Eliminating the need for straps, Ms. Gordon noted, saved crews nearly 8 hours as she estimates that method would have required an additional 10 minutes per limestone step during the installation process. The application of vacuum lifting also mitigated the risk of chipping the top-grade material by prying on it with a bucket or fork, she said, and curbed the possibility of damaging an adjacent patio on the South Lawn.
“We’re moving, fitting, lifting, spreading the mud and laying it down,” said Jessica Gordon. “All the re-handling; it adds up. With the remote operation, we can safely pick up and maneuver materials without compressors, hoses or other accessories presenting trip hazards. What really sold us is that everything is self-contained, in one unit.”
Timing of the South Portico project overlapped a remodel of 1600 Pennsylvania Avenue that was facilitated by NPS and the General Services Administration. The US$3.4 million ($4.3 million) project was completed in August and included the replacement a 27-year-old HVAC system along with renovations of the Navy Mess kitchen, West Wing lower lobby and IT system. According to the White House, these renovation plans had been approved by the previous administration.
The NPS’ Frederick, Maryland-based Historic Preservation Training Center focuses on maintaining and preserving icons of historical and cultural significance throughout the U.S. Jessica Gordon said that the agency handles about 35 to 40 projects a year, among its 3 divisions: Masonry, Woodcrafting and Carpentry. The scope of its masonry work includes 10 to 15 jobs a year, she said, with the typical project cost ranging between and estimated US$50,000 and US$400,000 ($64,000 and $512,000). According to Ms. Gordon, “Our work is project-based, so the rental option works well for us. Versatility is a major consideration.” Vacuworx Vacuum Lifting Systems were also used by NPS to help rehabilitate the steps that guide visitors to a memorial building at Abraham Lincoln Birthplace National Historical Park in Hodgenville, Kentucky.
The South Portico was originally constructed during the Monroe administration in 1824. New steps, constructed of Missouri limestone with a concrete base, were erected in 1952, during the presidency of Harry S. Truman. Springfield-based Phenix Marble Co. quarried the newly installed limestone. “The NPS has been handling maintenance projects at the White House since 2001,” said Ms. Gordon. “It’s enjoyable to be part of making history.”
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