|Restoration & Preservation Enterprises removed and rebuilt 765 windows on Chicago’s |
Marquette Building, a National Landmark designed in 1895 by Holabird & Roche.
Photo by J. Crocker.
Anon-descript industrial complex in Kankakee, IL, houses one of the high-tech secrets in window rebuilding: Restoration & Preservation Enterprises. Among top-flight architects handling high-profile renovation projects, however, word has spread, making principal Ray Drazen and his staff of 14 woodworkers and seven installers, the go-to-guys for restoring windows to state-of-the-art energy efficiency on high-profile properties around the U.S.
Architects and contractors praise R&P for historically precise craftsmanship executed with high-tech support. Drazen and his team are celebrated for gifted traditional wood window finishing, glazing and historic hardware rejuvenation.
| R&P restored 205 windows in the landmark Sears |
Chicago Homan Square project, handling interior
and exterior aspects.
“Windows are part of the original fabric of the building,” says Drazen, whose 24,000-square-foot plant includes SCMI CNC moulders and router, Northtech planer, Kern laser engraver, its own tool cutter, and plenty of computing horsepower to drive the demanding projects. Also on hand: a climate-controlled inventory of northern white sugar pine, Honduran mahogany, maple and red oak, some of it pattern grade.
Drazen says his clients take either a “conservation” or “restoration” approach, the former reusing original glass, the latter allowing for widening the channel in the window sash to hold more energy-efficient Thermopane-style double glazing.
“We are milling only what is necessary,” says Drazen, showing an antique pine double-hung window on which he has added mahogany strips to improve weather resistance. With digitally driven tools, “I can recreate it or replicate it exactly,” he says.
Drazen learned the wood trade at a furniture factory. He has also worked doing retail commercial interiors, eventually moving to restoring architectural millwork.
One key challenge in the projects is simple logistics: keeping track of hundreds of windows, each uniquely sized, even in cases like the 280-window Robert Vance Federal Building in Atlanta, the 765-window Marquette Building, or the 810-windows for a neoclassic 19th century Cook County, IL, government center.
When these structures were built, says Drazen, on-site window fabrication mills tailored windows to each opening. As buildings have settled, openings vary even more.
So window rebuilds are mostly one-offs, replaced typically in these steps: windows, consisting of two or more sashes, are carefully labeled using a placement number system established beforehand with architects, owners or general contractors to ensure proper communication and tracking of every sash and window component. Windows are then removed from the opening. A custom-milled cleat is installed to accept a 3/8-inch Plexiglass panel.
“That lets our workers repair the frames without intruding on the building occupants after the sashes are removed,” says Drazen. Hardware is removed and restored, often including chains and counterweights that balance older windows. Frame sashes are lined with bronze tracks, so sashes move freely. Work on site and at R&P happens simultaneously so sashes can be reinstalled within two to three weeks of removal.
Wood components are hand stripped; brick wood frames stripped, painted and recaulked, with damaged wood components from windows, sashes and frames replicated, using SCM equipment: a 6-head Superset class CNC moulder and Record 110 AL Prisma pods-and-rail 5 axis CNC router with ride-along tool changer.
|Digitally driven CNC wood components for windows, frames and doors are machined on |
a 6-head SCMI Superset CNC moulder (left) and Northtech dual helix NT 610 EL, which
planes both sides in one pass. Wood from each is near fully sanded on delivery.
|A factory video shows the SCM CNC|
router at work.
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