Accurate measurements are the foundation of a perfect roller blind installation. If your measurements are off by even a few millimetres, your blinds may rub against the frame or leave gaps that let in unwanted light. Taking the time to measure correctly ensures your custom blinds look professional and function as intended.
You must decide between an inside mount or an outside mount before you pick up your measuring tape. An inside mount sits within the window recess for a sleek, minimalist look. An outside mount covers the entire window frame and is better for blocking out light or hiding unattractive timberwork.
Preparing for Your Measurements
Use a metal measuring tape for every window in your home. Fabric tapes stretch over time and will give you an incorrect reading. Always record your measurements in millimetres to maintain precision.
Do not round your numbers up or down. Write down every measurement immediately so you do not rely on your memory. Check for any obstructions like window winders, handles, or locks that might get in the way of the blind.
Measuring for an Inside Mount
Measure the internal width of the window recess in three places. Take a reading at the top, the middle, and the bottom of the frame. Use the smallest width measurement of the three.
Measure the internal height from the top of the recess down to the windowsill. Take this measurement on the left, the centre, and the right side. Record the longest height measurement to ensure full coverage.
Check the depth of your window recess to ensure there is enough space for the roller mechanism. Most standard roller blinds require at least 60mm of depth for a flush finish. If your recess is shallow, you may need to consider an outside mount instead.
Measuring for an Outside Mount
Measure the width from the outer edge of the architrave on one side to the other. We recommend adding 50mm to each side if you do not have an architrave. This extra width helps reduce light bleed around the edges of the fabric.
Measure the height from where you want the top of the blind to sit down to your desired finishing point. This usually ends at the bottom edge of the architrave or the windowsill. If you want to create the illusion of a taller window, mount the blind higher above the frame.
Tips for Success
Double-check every single figure before you place your order. It is far cheaper to spend five extra minutes measuring than to pay for a replacement blind. Are your windows perfectly square? Old Australian homes often have settled, meaning your window frames might be slightly slanted.
Taking multiple measurements across the width and height helps account for these irregularities. If you feel unsure about your DIY skills, our team can assist with professional guidance. Would you prefer a professional to handle the technical details for you?
Key Takeaways
- Always use a metal measuring tape for accuracy.
- Record all dimensions in millimetres.
- Choose your mount type before starting.
- Measure width and height in three different spots.
- Use the smallest width for inside mounts and the largest width for outside mounts.
- Check for handles or locks that could block the blind.
- Phone: 0411 782 236
- Email: [email protected]
- Website: https://shuttersandshades.com.au

