Re-View was presented with the challenge of how to create a double hung window that carries a UL 752, Bullet Resisting Equipment, Level 8 rating.And by the way, it has to look like all of the other historic wood windows at the Kansas Statehouse project.
Our craftsmen had already restored hundreds of historic wood double hung windows on this project in different phases. We essentially had to reconstruct the original wood windows after they had been butchered by a previous window replacement project decades ago. Our carpenters rebuilt the frames in the field and then installed custom mahogany sash fabricated by the Re-View plant. The sash matched the original design except for the inclusion of energy efficient insulated glass. Since the average window was 56 inches wide by 150 inches tall, they were striking in a monumental way.
Then came the challenge to design and manufacture a ballistic version of these historic wood windows. The design would have to stand up to a 7.62 mm caliber, lead core, full metal copper jacketed ball, shot at 15 feet at an average velocity of 2,760 feet per second. There are several window manufacturers in the country who specialize in fabricating ballistic windows to meet these standards, but nobody can make one look like an exact replica of an 89 year old wood window. That is until Re-View was allowed to take a shot at it.
Re-View responded with a very unique design. The frame consisted of a 1 inch thick solid steel bar that was 8 inches wide. The frame parts were coped and butted and fully welded at the corners. Each simulated sash member was constructed of 2 inch square steel tubes with 1/2 inch plates covering the exterior surface and 1/4 inch plates covering the interior. The simulated meeting rail was constructed of solid steel with a machined glazing pocket. All connections were coped, butted, and welded. The glass was 2 inch thick laminated security glazing with a UL rating at Level 8. An interior of 9/16 inch thick African mahogany wood veneer covered all interior surfaces to give the window the same wood stained look as all of the original wood windows. We even installed fake pulleys, locks, and sash lifts to make the replica look like the originals.
Re-View tested the component pieces of the window design at a shooting range in rural Missouri by one of our craftsmen who specializes in ballistics. The test results proved to our engineers that the resulting window system could easily pass an official Level 8 test. We then contracted with Architectural Testing in York, Pennsylvania to conduct an independent test on a complete window specimen. The standardized test as conducted by ATI involved shooting the window 13 times in designated locations. Re-View's historically correct ballistic window passed with flying colors.
The Re-View plant manufactured only 11 of these mammoth windows measuring 5 feet wide by over 12 feet tall. Each window weighed in excess of 7,000 pounds. Our engineers and field carpenters had to develop a strategy just to install these behemoths that involved cranes and suction cup lifts. Sometimes our field installers wonder whether our management is insane to engage in such projects.If your historic preservation project is filled with challenges, give the people at Re-View a call at 816-741-2876.
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