Standing Seam Metal Roof Systems: Ideal for New Construction and Renovation
- By Jim Ladesich
- June 1st, 2002
Tuskegee University in Alabama originated in 1881 as a school where basic skills were taught in a one-room shanty. It has evolved into an academically prestigious university with 2,500 undergraduate and graduate degree students, a 5,500-acre campus and more than 70 buildings.
Under the administration of President Benjamin F. Payton, more than $90 million has been invested in the physical plant. Renovations have sought to preserve the more notable facilities while upgrading their structural integrity, functionality and the consistency in their architectural continuity, explains Clifford Wesson, Tuskegee’s construction manager for a recent renovation.
Willcox C, a campus landmark at Tuskegee University, gained renewed life and a new mission following a $2-million reconstruction project. The building is part of a five-building complex where students of a bygone era learned construction trades and other vocational skills. The legacy seems appropriate for a building that now serves as the School of Architecture. Those training for the profession can see firsthand how the 70-year-old building was stripped to its brick shell and steel trusses before conversion to modern standards by the design/build team of A.G. Dre-Co, Inc., Tuskegee, and Stansell & Associates, officed in Montgomery, Ala.
The 14,300-sq.-ft. building is one of two structures that were originally scheduled for extensive rehab projects until a budget shortfall deferred improvements to the second building. The scope of work underwent even further change when administrators scrapped plans to add a second floor within Willcox C because the structure’s 17-ft. clearance between existing concrete slab and steel roof trusses would not accept the modification. Instead, the structure was completely gutted before receiving new interiors; new mechanical, electrical, plumbing and life-safety systems; a window replacement; exterior masonry restoration; and a Colonial Red standing seam metal roof system with a 7:12-in. pitch.
The 16-in., solid brick walls were repaired where necessary and fully repointed during the building’s exterior facelift. This coincided with replacing the existing windows with aluminum, 1/2-in. insulating units. Formidable, eight-ft.-deep steel trusses, ductwork and decking were left exposed in the three architectural studios created within the short legs of the H-shaped footprint.
In recent years, Tuskegee administrators have adopted Colonial Red as an architectural standard for the increasing use of standing seam metal roof systems (SSMRs) on campus facilities. Specifications for the Willcox C roof also required a UL Class 90 Wind Uplift rating and 70-percent Kynar base for factory-applied color coating.
RCI Contractors & Engineers, Inc., based in Tuscaloosa, Ala., was awarded the subcontract for the reroofing portion of the project. Butler Manufacturing supplied both the slope build up/roof support system and the 24-gauge VSR architectural standing seam metal roof system. The building was altered to a hip-roof profile that cantilevers four ft. over the building’s brick. A two-ft.-high soffit, clad with the same red metal panels, and a color-coated custom gutter were also fabricated from Butler material. The complete assembly imposed a roof load of only four lbs. psf on the structure, well within the range of what the building would accept. Because VSR was developed to serve both as an architectural and structural standing seam metal roof system, it was applied over five-ft. purlin spacings without an underlying solid substrate.
The installation began by using three-in. wood screws at 30-in. spacings to attach four-in. purlins at five-ft. spacings across one-in. plywood decking. The fastener spacings changed to two-ft. and one-ft. at the corners and two-ft., six-in. at the eaves. The intervals were established by pull-out tests conducted by RCI, coupled with Butler wind uplift data.
The purlin base members then accepted the five-ft. by five-ft. slope build up and support grid. It reached 16 ft. in height at the main ridgeline once in place. Because Butler Z purlins can only create a 6:12-in. maximum slope, a creative solution was needed to gain the one-in. shortfall in the pitch sought for the roof. RCI achieved the added inch of slope by running 90-degree Z purlins perpendicular to the eaves and spanning them with 15-ft.-long, 1 1/2-in. members. A four-mil polyethylene vapor retarder was then added below the VSR panels that were joined into standing seams using a portable electric seamer. The finished roof has a 20-year weathertight warranty backed by Butler.
The reconstructed building subdivides into 12 offices, conference area, a model shop, storage area and offices for student chapters of the American Institute of Architects and a general contracting association.
Jim Ladesich is a Shawnee, Kan.-based freelance writer with experience in higher education issues.