Accurate measurements are the foundation of a well-fitted custom blind. A few careful checks can help your cellular blind sit neatly, operate smoothly and provide the light control and privacy you expect. This guide explains what to record before you place an order.
What you need
- A rigid metal tape measure
- A pencil and paper, or a notes app
- A step stool if the top of the window is out of reach
- A second person for wide or high windows
Measure every window separately, even if two openings look identical. Small construction differences are common.
Choose an inside or outside mount
An inside mount sits within the window recess and gives a clean, built-in appearance. It requires enough clear depth for the headrail and an opening that is reasonably square. An outside mount attaches to the wall or trim around the window. It can cover an uneven recess and may reduce visible light gaps when the blind is closed.
Before measuring, check handles, locks, vents, tiles and projecting trim. Make sure the blind will have room to move without touching an obstruction.
How to measure for an inside mount
- Measure the width in three places: across the top, middle and bottom of the recess.
- Measure the height in three places: on the left, in the centre and on the right.
- Measure the usable depth: record the shallowest clear depth after allowing for handles and other obstructions.
- Record the exact opening: do not make an unrequested deduction. Follow the measuring instructions shown with the product when entering your order dimensions.
Use the same unit throughout the order. Millimetres are helpful for precise custom measurements. If you start in inches, avoid switching units halfway through.
How to measure for an outside mount
- Decide where the headrail will be installed above the opening.
- Measure the total width you want the blind to cover, including the overlap on both sides.
- Measure from the planned top position to the point where the blind should finish.
- Check that the mounting surface is flat, strong and clear of handles or furniture.
A larger overlap can improve privacy and reduce edge light, but the blind must still clear nearby walls, cupboards and handles.
Common measuring mistakes
- Measuring only once or in only one position
- Assuming matching windows have matching dimensions
- Using a soft fabric tape that can stretch or sag
- Rounding measurements too early
- Forgetting the window handle or the depth needed by the headrail
- Entering width and height in the wrong fields
Final checklist before ordering
- The mount type is confirmed
- Width and height have been checked twice
- The selected unit matches the numbers entered
- The recess depth and all obstructions have been checked
- Each window is labelled clearly
Ready to order? Visit the FAIZ custom cellular blind product page to select your options and enter the measurements. You can also review our shipping information and learn about FAIZ BLINDS before checkout.
Continue your research
For bedroom light control, read Blackout Cellular Blinds for Better Sleep. To understand the insulating design, see Cellular Blinds for Insulation and Energy Efficiency.