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5 most common mistakes when measuring fabric roller blinds - and how to avoid them

Accurate measurement is the foundation of a successful installation of fabric roller blinds. Even a small inaccuracy can mean that the blinds will not fit perfectly or not function properly. IIn this article, we walk you through the most common mistakes that catch first-timers out - and, more importantly, how to avoid them.

1. Incorrect width measurement for recess installation

Most common mistake: Measuring the exact size of the opening without deducting any allowance.

 

Why it's a problem: The blind won't fit into the opening or will stick out at the sides.

 

How to do it correctly:

  • Measure at the top part of the opening (not at the bottom)
  • For parallel window openings, subtract 2 mm (1 mm on each side)
  • For non-parallel or crooked windows, subtract preferably 4 mm
  • Check if the opening is the same width at the top and bottom

2. Neglecting the width of the brackets when mounting in front of the window

Roller blind in the walk-in closet

Most common mistake: Ordering a blind that is the same width as the window.

 

Why it's a problem: The blind will not extend enough and will not effectively shade.

 

How to do it correctly:

  • Consider the width of the brackets, which is added to the width of the fabric
  • Plan fabric overlap on both sides for better shading
  • The recommended overlap is 60-120 mm on each side
  • Total width of the blind = width of the fabric + width of the brackets

💡 Tip: You can find the exact dimensions of the brackets and a calculator for the calculation in our dimension table.

 

Note: The larger the overlap, the better the blind shades (especially important for blackout blinds)

3. Incorrect height measurement

Most common mistake: Measuring from the ceiling to the floor instead of from the mounting point to the desired end of the blind.

 

Why it's a problem: The blind will be too long or too short.

 

How to do it correctly:

  • Measure from the place where the brackets will be to the point where the blind should end
  • For recess installation, leave a 5-10 mm allowance at the bottom
  • For front-of-window installation, account for the height of the brackets
  • Consider sills, radiators, and other obstacles

 

💡 Tip: After installation, you can use the controller to set where the blind stops - you don't have to be millimeter precise.

4. Failing to recognize unsuitable walls or ceilings

Most common mistake: Planning installation into drywall without reinforcement or old plaster.

 

Why it's a problem: The blind can fall or come loose.

 

How to recognize a suitable surface:

Suitable: concrete, brick, wood, drywall with metal profiles

Unsuitable: drywall without reinforcement, old crumbling plaster

Test: If the surface bends or crumbles when pressed, it is not suitable.

Transparent fabric blind in living room

🛠️  Solutions for problematic surfaces:

  • For drywall, use special anchors or mount into metal profiles
  • For old plaster, consider professional reinforcement

5. Not considering the direction of fabric roll

Most common mistake: Not considering obstacles in the room when choosing the direction of unrolling.

 

Why it's a problem: The fabric can hit handles, radiators, or furniture.

 

How to do it correctly:

  • Standard unrolling: fabric unrolls behind the blind
  • Reverse unrolling: fabric unrolls in front of the blind
  • Check all obstacles: window handles, radiators, sills, furniture
  • Try simulating fabric movement before ordering

💡 Tip: Use a piece of string or tape measure to simulate fabric movement in the space.

Bonus tip: How to double-check your measurements

Fabric roller blind

Before finalizing blind orders, we recommend:

 

Double check: Measure everything again - ideally with the help of a second person

 

Draw a sketch: Record all dimensions and obstacles

 

Use tolerance: Our blinds have a tolerance of 5 mm - perfection is not required

 

In case of doubt: Contact us or consider professional measurement services

Correct targeting is not rocket science, just follow a few basic rules. If you're unsure or have a non-standard space, don't hesitate to contact professionals. Even a small measurement error can cause significant complications during installation.

Remember: Better to measure twice and order once than to deal with complaints and replacements.

Go to the measuring guide

 

Need help with measurements or have a non-standard space? Contact us or consider professional measurement and installation services via BEMATECH.