The state of North Carolina chooses “turnkey” precast concrete construction to improve speed, quality control and safety – and to cut costs.
By Barbara Bogo
When the North Carolina Department of Corrections (NC DOC) needed fast-track construction of three 1,000-cell high-security prisons, it turned to precast concrete for the solution. The prisons, erected in Alexander, Anson and Scotland Counties, used a first-of-its-kind project delivery methodology.
The North Carolina Central Engineering Department reported that project costs were reduced by using a single contractor that cut completion time nearly in half compared with conventional building processes.
It took approximately 18 to 24 months to finish the three new correctional facilities. In contrast, conventional construction would have taken an additional one to two years, if not longer.
The North Carolina prison projects consist of the construction of three identical prisons based on a prototype design by the State of North Carolina. Each prison is approximately 500,000 square feet and constructed of precast concrete modular cells, structural precast concrete and concrete masonry units. Each prison is composed of 992 inmate cells, 26 day rooms, 11 control rooms, administrative offices, a central energy plant and recreational facilities.
Each facility will be identical in design, layout, and installed systems and equipment. “Because we are building exactly the same structure three times with a staggered schedule of three months, we are able to address problems and issues at the Scotland project and convey that information to the Anson and Alexander projects before they complete that scope of work,” said Adam Pearlman of Centex Rooney Construction Co., the general contracting firm.
The facilities will include seven interconnecting buildings. Five of these buildings are for inmate housing. Three four-story buildings will have a three-finger design for the general population and two two-story buildings for segregation housing. Each of the three prisons is identical in design and function with the exception of local site work.
NC DOC selected structural precast quad cell modules that were required to be fully outfitted before erection. The four-cell precast modules included furniture, lighting, electrical components, plumbing, finishings, vertical and horizontal windows, and openings as specified in the prototype plans. The modules even featured an exterior form liner finish to provide an aesthetically appealing facade.
Each quad cell module is 30 feet long and 12 feet wide, weighs 95,000 pounds and contains 23 cubic yards of concrete. To support this project, Oldcastle Precast Modular Group built a new factory in Fuquay-Varina, N.C., to build the 3,000 precast cells and additional precast components. The precast concrete units are load-bearing, monolithically cast, five-sided modules (cast without a floor slab). The exterior walls of the modules are cast with a 10-inch back wall (a 5-inch structural wythe, 2 inches of rigid insulation, and a 3-inch exterior wythe) and a form liner finish.
Each facility consisted of more than 1,488 precast modular components, 744 of which were precast cell quad-modules, 372 balcony slabs and 372 plenums. Despite the large number of components, each facility required only four months to erect.
“Bringing this facility on line in 21 months was a major undertaking,” said Ted Adams, who represents Centex Rooney. But thanks to precast concrete construction, the turnkey units reduced time and costs while improving quality and safety.
To find a manufacturer of this product in your area or for more information, visit NPCA’s Web site at www.precast.org or call toll free (800) 366-7731.
Project Name: High-security prisons
Owner: North Carolina Department of Corrections
Contractor: Centex Rooney Construction Co., Orlando, Fla.
Architect: Little & Associates, Charlotte, N.C.
Precast Engineer: H. Wilden & Associates, Allentown, Pa.
Precast Manufacturer: Oldcastle Precast Modular Group, Telford, Pa.