This disclosure may generally relate to drilling operations and, more particularly, to systems and methods for sidetracking an existing well. Specifically, examples of the present disclosure may include creating a window by introducing a pH-modifying fluid downhole to degrade a portion of a casing string, thereby creating the window through which a secondary wellbore may be drilled. A method for creating a window in an oilfield tubular may comprise of providing a pH-modifying fluid in the oilfield tubular disposed in a wellbore and contacting a degradable section of the oilfield tubular with the pH-modifying fluid to degrade at least a portion of the degradable section and form an exit window in the oilfield tubular.