Bay and bow windows are more than just windows. They’re combinations of windows that reach out into the world. Even with limited wall space, a bay or bow window allows you to have more windows to capture the view and enjoy the scenery. Bay windows are typically made up of three windows - a fixed window in the center with venting single/double-hung or casement on either side. A bow window is created by joining four or more windows together to form a graceful curve. Pella bay and bow windows come factory-assembled and ready to install. Bays include optional birchwood head and seat boards.