We have an old, large single pane picture window. This window is the most important window that allows us to see the ocean view. It is very cold and windy here during the winter. We have recently purchased a window that is somewhat smaller than the existing pane size. Instead of removing the existing window, which is very heavy and difficult to dispose of, we want to attach the new window frame to an old window’s glass pane. The new Anderson window is wood frame inside and outside is a vinyl. I am planning to attach the vinyl to the existing single pane surface, hoping to reduce any air getting inside. However, I am concerned that it may still create moisture between the new and the old windows, and thus no longer have the view of the ocean. I am not sure as to what type of adhesive will prevent moisture. Any suggestions?