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Daylight Opening and Glass Opening Sizes
Illustration Of Daylight Opening and Glass Opening
DAYLIGHT OPENING: The area of glass visible in a glazed sash. For Standard Storm Sash the GLASS SIZE is 5/16" wider and 5/16" higher than the daylight opening.
GLASS OPENING: The glass opening is measured glass rabbet to glass rabbet. For Standard Storm Sash the GLASS OPENING is 3/8" wider and 3/8" higher than the DAYLIGHT OPENING
GLASS SIZE: The actual Glass Size is 1/16" less in both Width and Height than the Glass Opening to provide clearance for the glass. For STANDARD SIZE 2-light Storm Sash the GLASS SIZE is even inch width x even inch height; i.e. 24 x 28.
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![]() Daylight Opening and Glass Opening Measurements |