Accurate window measurements ensure your blinds fit perfectly, whether you mount them inside the frame or on the wall. Inside mounts use the narrowest width and the longest height within the frame. Outside mounts require extra allowance to cover the window and the architrave. This guide shows you how to measure correctly and avoid mistakes, and when to call the experts for a free measure and quote.
Inside Mount vs Outside Mount: The Simple Difference
An inside mount sits within the window frame for a clean, built-in look. It works well when the frame is deep enough and perfectly square. Use it for sleek options like Roller blinds or Roman blinds.
An outside mount attaches to the wall or architrave and covers a larger area. It creates the illusion of a bigger window and hides uneven frames. It’s ideal for slim Venetian blinds or when you need blockout coverage.
The Measuring Checklist (Do This Every Time)
- Decide whether you need an inside or outside mount and plan accordingly.
- Use a steel tape measure, not a fabric one, and measure in millimetres.
- For inside mounts, measure the width at the top, middle and bottom, and record the smallest.
- For inside mounts, measure the height on the left, middle and right, and record the largest.
- For outside mounts, measure the exact area you want to cover and add at least five centimetres to both width and height.
Write your measurements down clearly and double-check before ordering. For detailed step-by-step instructions, see the Bunnings guide to measuring for inside-mounted blinds.
Common Measuring Mistakes That Cause Poor Fit
Rounding measurements up or down is a common mistake that leads to gaps or tight fits. Always write down the exact millimetres to avoid guesswork. Using a cloth tape can stretch and give inaccurate readings; use a steel tape instead.
Measure every window because even identical-looking frames can vary. Check the frame depth to ensure inside mounts have enough room for brackets. Never estimate allowances for outside mounts; add generous coverage to block light and improve privacy.
When to Book a Professional Measure
If your windows are high, wide or unusually shaped, consider booking a professional measure. Tricky bay windows, corner windows or sliding doors need precise calculations to avoid gaps. Professionals can also advise on bracket placement and hardware. If you suspect hazardous materials like asbestos, or if you need to use a ladder, play it safe and call a trained installer. Following home ladder safety tips will help you avoid injury.
A professional measure and quote is often complimentary and takes the stress out of ordering. You’ll get the right advice on style and fit, saving you time and cost.
Conclusion
Measuring correctly is the key to perfect-fit blinds. Decide on the mount, follow the checklist and double-check your numbers. Use our roller, roman or venetian products as inspiration for each room.
When in doubt, book a Free measure & quote to enjoy effortless installation and peace of mind.