How to Measure Windows Correctly for Custom Blackout Curtains

Measuring windows for Custom Blackout Curtains is not complicated, but it does need attention to detail. Small mistakes in measurement can lead to gaps, uneven length, or curtains that simply don’t work as expected. Taking a few extra minutes at the beginning usually makes the final result much better.

Why accurate measurements matter

Curtains are one of those home items where size really affects performance. If the fit is off, even by a few centimeters, light can leak in from the sides or top. This is especially noticeable with blackout curtains, where the goal is usually a darker and more controlled space.

Getting the measurements right helps the curtains look cleaner and work more effectively.

What you need before starting

You don’t need many tools. A simple metal tape measure, a pencil, and a notepad are usually enough. If the window is tall, a small step ladder can help you reach the top safely.

The key is to measure carefully and avoid guessing or rounding too early.

Inside mount vs outside mount

Before measuring, it helps to decide how the curtains will be installed.

Inside mount means the curtains sit inside the window frame. This gives a neat and minimal look, but it requires very precise measurements.

Outside mount means the curtains cover the area outside the frame. This is more common for blackout curtains because it helps block more light and gives better coverage overall.

How to measure width

Start by measuring the full width of the window frame. For inside mount, you usually stick closely to the exact measurement.

For outside mount, it’s better to extend the width slightly on both sides. This helps reduce light gaps and improves privacy. Many people prefer a little extra width rather than a tight fit.

How to measure height

For height, measure from the top of the window frame down to the point where you want the curtain to end.

If you are using an outside mount, include the space where the curtain rod will sit. Some people also choose to mount the rod slightly higher than the window to make the room feel taller and reduce light entering from the top.

Don’t forget the rod and fabric space

One common mistake is forgetting that curtains need space to hang and fold. The rod position and fabric fullness can slightly change how the curtain falls once installed.

Taking this into account helps avoid curtains that end up shorter or narrower than expected.

Measuring windows correctly is a small step, but it makes a big difference in how custom blackout curtains perform. When the fit is right, the curtains look more natural and do a better job controlling light and privacy without any extra effort.

There is also a seasonal offer available:
Summer Blackout Sale - Code: BLACKOUT6
Free Shipping Over $100
Custom Curtains 20% OFF: SUMMER20

If you want to explore more options or learn about custom sizing and materials, you can visit https://dwcnhome.com/.