A window assembly for an aircraft includes a window frame being arranged bordering a window opening in a hull of the aircraft, a window seal being attached to the window frame, a window being supported by the window frame and sealed to the window frame by the window seal, a window retainer covering the window seal and the window frame from the inside of the aircraft, and a transparent vapor barrier being supported by the window retainer and covering the window from the inside of the aircraft such that an air gap is formed between the window and the transparent vapor barrier.