The Measure-Once Checklist

What's inside

• Record all width and height readings before choosing which to submit.
• Check mounting depth against the exact product and lift option.
• Inside vs outside mount, and who applies the width deduction.
• Review the selected product’s measuring instructions before ordering.

1. 1Grab a steel tape measure — never cloth, which sags and lies.
2. 2Record width at the top, middle and bottom. The seller’s product guide determines which reading to use.
3. 3Record height at the left, center and right. Keep all three readings.
4. 4Measure the flat depth to the glass or nearest hardware at the shallowest point.
5. 5Note cranks, handles, and sensors the blind must clear.
6. 6Decide inside or outside mount — outside if the frame is shallow or out of square.
7. 7For an outside mount, follow the exact product’s overlap and mounting-height instructions.
8. 8Confirm who applies the deduction in the seller’s measuring guide.
9. 9Check the seller’s minimum and flush depth against your measured depth.
10. 10Recheck your readings and the seller’s current return and remake terms before ordering.