Picture Window 48 X 60, A 60 x 48 window is a standard-sized window that measures 48 inches wide and stands 60 inches tall. It is also referred to as a 5×4 window if the measurements are in feet. These standard windows are designed for a rough opening of 47.75×59.75 or 47.5×59.5, meaning the actual window size is 1/4 or 1/2 smaller.
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Picture Windows | Types of Picture Windows | Clean the Picture Window - Civil~Step
civilstep.com

Picture Windows | Types of Picture Windows | Clean the Picture Window - Civil~Step

All info about picture window......Picture windows are a great way to frame a beautiful view from the outside....