Wooden Blinds Measurement Guide

Measuring your windows to decide which size of wooden blind, whether it is a horizontal or vertical blinds for your bay windows, to order is easy. Just follow these simple step to find out how to measure your bay windows for blinds. With this measurement guide you will be able to get the correct size of bay window blinds and curtains.

Please use a metal tape measure to take measurements and use centimetres to the nearest 0.1cm.

Recess Fit Take 3 measurements for the width of the window recess as shown in the picture. Take the smallest of these measurements. Do the same for the drop, again taking the smallest measurement. Deduct at least 1.5cm from the width measurement to allow for clearance. You do not need to deduct anything from the drop measurement for Venetian, Roman or Roller Blinds. For Vertical blinds we recommend deducting 2cm. The measurements used on our site are the exact blind measurements. The drop includes any pelmets or valances at the top of the blind.

Outer Fit

• Just measure the exact area you would like the blind to cover, as shown in the picture below.
• For Vertical blinds we recommend deducting approximately 2cm from the drop to allow for clearance.

All our blinds come with all the fittings you'll need, along with instructions for easy installation.

You may also like to see our wooden blinds installation guides.

If you have any other queries about installation or measurements, please feel free to contact us.

Measuring for Bay Windows Blinds

1. Determine the depth of the blinds you are mounting and use this for the width of your cardboard:
   • 25mm slats = 40mm depth
   • 35mm slats = 60mm depth
   • 50mm slats = 80mm depth
2. Cut two pieces of cardboard (depth determined from 1 above) wide by 30cm (12") long.
   Important: If spacer blocks or extension brackets will be used for extra clearance on outside mounts, add the amount of extra clearance to the width dimension of the cardboard before measuring.
3. Place the strips in the left angle first, and bring them together until the front corners of the cardboard meet. Mark points "A" and "B".
4. Repeat this step for the right side angle, marking points "C" and "D".
5. Measure between points "B" and "C" to obtain the width measurement of the center window treatment.
6. Measure from point "A" outward to the desired width to obtain the width measurement of the left window treatment.
7. Measure from point "D" outward to the desired width to obtain the width measurement of the right window treatment.
8. Deduct about ¾cm (7.5mm) from each of your measurements to allow for clearance.

Square Bay Windows

• Type A



Use this method to cover the front window more effectively. The best method if you want to stop direct light from the front or to stop people looking in directly from the front. There may be a small gap where the side blinds meet the front blinds but this is usually obscured by the window frame at the corners.

Taking measurements

Front blind
Measure the width of the recess where the front blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct 1.5 cm for clearance.
Side blinds
Measure the width of the recess where the first side blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct the depth (projection from window) of the bay window blind you are going to order. See depth of blinds guide. Deduct 1.5 cm for clearance. Repeat this for the other side bay window blind.

E.G. for 25mm Express blinds - depth 4cm (projection from window)

Front bay window recess width 200cm.
Deduct 1.5cm for clearance 200cm - 1.5cm = 198.5cm.
You should order the front blind at 198.5cm.

Side bay window recess width 95cm.
Deduct depth (4cm) 95cm - 4cm = 91cm.
Then deduct 1.5cm for clearance 91cm - 1.5cm = 89.5cm.
You should order the side blind at 89.5cm.



• Type B



Use this method to cover the side windows more effectively. The best method if you want to stop direct light from the sides or to stop people looking in directly from the sides. There may be a small gap where the front blinds meet the side blinds but this is usually obscured by the window frame at the corners.

Taking measurements

Front blind
Measure the width of the recess where the front blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct two times the depth (projection from window) of the bay window blind you are going to order. See depth of blinds guide. Deduct 1.5 cm for clearance.
Side blinds
Measure the width of the recess where the first side blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct 1.5 cm for clearance. Repeat this for the other side bay window blind.

E.G. for 25mm Express wooden blinds - depth 4cm (projection from window)

Front bay window recess width 200cm.
Deduct two times the depth (8cm) 200cm - 8cm = 192cm.
Then deduct 1.5cm for clearance 192cm - 1.5cm = 190.5cm.
You should order the front blind at 190.5cm.

Side bay window recess width 95cm.
Deduct 1.5cm for clearance 95cm - 1.5cm = 93.5cm.
You should order the side blind at 93.5cm.


• Type C



Use this method if you do not want the wooden blinds to overlap at the corners or if you require a more symmetrical look. There may be a small gap where the front and side blinds meet but this is usually obscured by the window frame at the corners.

Taking measurements

Front blind
Measure the width of the recess where the front blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct two times the depth (projection from window) of the bay window blind you are going to order. See depth of wooden blinds guide. Deduct 1.5 cm for clearance.
Side blinds
Measure the width of the recess where the first side blind will go. Make sure you take the smallest measurement if the recess or frame varies from top to bottom. Deduct the depth (projection from window) of the bay window blind you are going to order. See depth of blinds guide. Deduct 1.5 cm for clearance. Repeat this for the other side bay window blind.

E.G. for 25mm Express wooden blinds - depth 4cm (projection from window)

Front bay window recess width 200cm.
Deduct two times the depth (8cm) 200cm - 8cm = 192cm
Then deduct 1.5cm for clearance 192cm - 1.5cm = 190.5cm
You should order the front blind at 190.5cm.

Side bay window recess width 95cm.
Deduct depth (4cm) 95cm - 4cm = 91cm
Then deduct 1.5cm for clearance 91cm - 1.5cm = 89.5cm.
You should order the side blind at 89.5cm.
Check the measurements of any other side blinds separately as they may be different