IMPORTANT NOTE: On roll-up shades the fabric will be 1' to 1 1/4' narrower than the width measurement. This allows for the bracket and clutch, and provides space for the roller shade to operate properly.
WIDTH: Width is measured to outside edges of the mounting brackets. Measure the width of the opening in 3 places (top, middle, and bottom). Take the smallest of the 3 measurements (rounded to the nearest 1/8 inch) and write it down. This is the width you will order. Do not make any deductions! We will make the necessary deductions to provide space for operation.
HEIGHT: Measure the desired opening height in 3 places (left, middle, right) only this time take the largest measurement (again rounded to the nearest 1/8 inch). This is the height you will order. The factory will make no deductions or additions to the length measurement.