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Avoid Common Mistakes: Expert Tips for Measuring Vertical Blind Slats by Steve

Avoid Common Mistakes: Expert Tips for Measuring Vertical Blind Slats by Steve

Learn how to measure vertical blind vanes aka slats

Measuring vertical blind slats can be a tricky task, especially for those new to the world of window treatments. A minor mistake in measurement can result in ill-fitting blinds that either let in too much light or simply look out of place. Fortunately, you’ve come to the right place! With Steve’s expert tips, you can avoid these common mistakes and measure your vertical blind slats like a pro.

For a more in-depth explanation and practical demonstrations, you can check out our complete video tutorial.

Table of Contents

  1. Tools You’ll Need
  2. Preparation Steps
  3. How to Measure
  4. Common Mistakes to Avoid
  5. FAQs
  6. Conclusion

Tools You’ll Need

  • Metal Tape Measure
  • Notepad and Pen
  • Stepladder (if necessary)
  • Calculator (optional)

Preparation Steps

Before you start, it’s crucial to be well-prepared. Here’s what you need to do:

  1. Clear the Area: Make sure the window area is free of any obstructions.
  2. Check Your Tape: Always use a metal tape measure for accuracy.
  3. Choose a Mounting Style: Decide whether you’re going for inside mount or outside mount, as the measuring technique will differ for each.

How to Measure

Inside Mount:

  1. Width: Measure the exact inside width of the window frame in three places (top, middle, bottom). Use the smallest measurement.
  2. Height: Measure the inside height at three different points. Again, use the smallest measurement.

Outside Mount:

  1. Width: Measure the desired width where the blinds will be mounted. Include an extra 2-3 inches on each side for optimal light blocking.
  2. Height: Measure the height from the point where the headrail will be mounted down to where you want the blinds to end.

Common Mistakes to Avoid

  • Rounding Numbers: Always jot down exact measurements. Rounding up or down can result in ill-fitting blinds.
  • Using a Cloth Tape Measure: These can stretch and give inaccurate measurements.
  • Ignoring the Smallest Measurement: Always use the smallest width and height when ordering blinds for an inside mount.
  • Forgetting the Depth: If you’re going for an inside mount, make sure your window frame has enough depth to accommodate the blinds.


Q: Can I use a ruler instead of a tape measure?
A: While it’s possible, a metal tape measure is far more accurate for this type of project.

Q: What’s the difference between ‘slats’ and ‘vanes’?
A: Both terms are often used interchangeably. However, ‘vanes’ usually refer to vertical blinds, while ‘slats’ are often horizontal.


Measuring for vertical blind slats doesn’t have to be a daunting task. With the right tools and Steve’s expert tips, you can achieve accurate measurements and perfectly fitted blinds. Remember, the key to a successful installation lies in the details, so always measure twice and order once.

Expert Tips by: Steve

By following this comprehensive guide, you’ll avoid the common pitfalls many encounter when measuring for vertical blind slats. Happy measuring!

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