A.Kelly Reynolds responds: All three model codes limit the maximum height of the sill to 44 inches. There is no minimum distance that a window must be from the floor, even for second-story windows. However, if the window extends to within 18 inches of the floor, it must either be safety-glazed or have a bar or other physical barrier to prevent someone from falling into the glazing.
To meet code, the open area of an egress window must have a minimum width of 20 inches and a minimum height of 24 inches, plus the opening must be a minimum of 5.7 square feet. Note that a 24x20-inch window does not meet code, because it creates only a 3.3 square foot opening. To comply, the window open area would need to be at least 24x34...
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