How to Measure for a Wall-Fixed Bay Window Curtain Track
For floor-length curtains hanging in front of the window sill
If you’re planning floor-length curtains that hang down in front of your bay window sill, the measuring position changes slightly.
This guide shows you exactly where to measure from and what sizes we need. Don’t worry if your bay window isn’t exactly the same shape as the examples below — the measuring method is the same for most bays.
Is this the right guide for you?
This page is for you if:
- your curtain track will be wall-fixed
- your curtains will hang in front of the bay
- your curtains will be floor-length
- your window sill is shallow or does not project out
If your curtains will stop at the sill and stay within the bay, you’ll want the sill-length guide instead.
Important: is your window sill shallow enough?
This type of setup only works properly if your window sill is shallow or sits neatly within the bay.
If your sill projects out more than a few cm’s from the wall, a wall-fixed track can cause the curtains to sit at an angle as they drop down.
This means the curtains won’t hang straight, and you may also find big gaps on the sides.
If your sill sticks out more than a few cm’s, then a ceiling-fixed track is usually the better option as it allows the curtains to hang straight down in front.
Different bay shapes, same measuring method
Every bay window is slightly different, but the measuring method is the same.
You are measuring the shape where the curtains will hang — not just the window itself.
How to measure your bay window in 3 simple steps
Once you know where to measure from, the process is straightforward.
Step 1: Measure each section along the front edge
Measure each straight section following the front edge of the sill.
You should measure the width of each wall section over the windows.
This is where the curtain track brackets will fit.
Step 2: Measure across the front of the bay
Measure across the full width of the bay at the front position.
This size is from the front corner of the bay on one side to the other front bay corner.
Step 3: Measure the diagonals
The diagonal measurements allow us to calculate the angles correctly.
Again these should be measure from the bay corners over the top of your windows.
So from the external corner to the opposite internal corner.
It’s simpler than it looks
Once you understand where to measure from, the process becomes very straightforward.
Take your time, measure in centimetres, and write each size down as you go.
Want to make it even easier?
You can use one of our printable measuring templates to guide you.
Example: 5 sided bay measuring template
Fill it in as you go, then either upload a photo or enter the sizes manually when ordering.
Still unsure? Just ask
If you’re unsure about anything, send a photo and I’ll take a look.