Bathroom Window Height From Floor . One or more walking surfaces within 36 inches (914 mm) horizontally of the glazing. Where to install windows with tempered glass is not just dictated by the height of the window. CREED EDesign Bathroom From Concept to Sneak Peek from carolreeddesign.blogspot.com Bottom edge less than 18 inches (457 mm) above the floor. It seems 32 to 36 is standard for height from floor. Windows are a very essential part of any house.for a simple residential building or house, a minimum of 15 % area of the room is allowed to provide for window openings.