In 1925, George Silbernagel set off with his sons to start their own wood door and window sash factory. From their factory on Lemke Street, Silbernagel and Sons helped provide the building materials for homes and businesses across Wisconsin. After a fire burned it down in 1934, they purchased the old Wausau Novelties Company factory, and moved operations to Rosecrans Street on the west side.
After George died in 1936, his sons sold to Harris Brothers of Chicago, who would further develop the small window company, which was eventually renamed to Crestline.
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In addition, you can learn about the Window Exhibit and other window companies here: