As a precursor to forming a glass sheet, a soot layer is formed on a deposition surface using a roll-to-roll glass soot deposition process. A soot layer-separating device is configured to bring a stream of gas into contact with at least a portion of a free surface of the soot layer. The impinging gas stream affects local thermal expansion stresses at the soot layer/deposition surface interface, which separates the soot layer from the deposition surface.