How to measure for blinds


Lynne Whitteker
Written by Lynne Whitteker
Russells Consultant
Explore more advice and tips
Related posts
Join our style club

Sign up and create a home you love with expert décor tips, seasonal solutions, the latest trend inspiration, exclusive offers and more

If you’ve decided on blinds, and decided to investigate ready-made or an online supplier, you’ll need to take your own measurements. Here’s a quick guide to getting it right.

Inside or outside mount

  • Do you want your blinds mounted on the inside or outside of the window frame? This is the first decision to be made before any measuring begins.
  • An inside mount offers a streamlined, more minimalist look. With an inside mount the headrail sits back in the window frame, accentuating the size of the window and the frame itself. If you have decorative window surrounds, show them off with an inside mount. To allow the blind to fit flush with the frame make sure it’s deep enough to accommodate the width of the headrail; this will vary depending on the style of blind but as a guide, you will need 2.5 to 10cm room, and even more for vertical blinds to allow enough room to open the slats. It also requires a small amount of space on either side to ensure the upward and downward movement of the blind isn’t hindered.
  • With an outside mount, the blind is mounted either at the top of the actual window frame or on the wall above, outside the frame completely. You can add a style element in the form of a decorative pelmet to hide the fittings. An outside mount looks simple and is easy to operate. It also offers more style flexibility because you’re not as restricted by the size of the blind as you are with an inside mount. An outside mount gives the illusion of a longer and/or wider window.

Russells blinds

Venetian blinds

Inside mount

  1. Measure the depth of the window casing to ensure it’s big enough.
  2. Measure exact window width in three places (from frame to frame) – at the top, middle, and bottom. Use the narrowest width.
  3. Measure exact window height in three places (from the top of the frame to the sill) – in the middle and to the left and right. Use longest height*.

Outside mount

  1. Measure exact width where the blind headrail is to be placed.
  2. Add at least 10cm for overlap (5cm per side) for good light control and privacy.
  3. Measure exact height from the top of the proposed headrail location to the base of the sill or where you want the blind to reach to when fully extended. Add about 3cm for good light control.

Vertical blinds

Inside mount

To hang vertical blinds inside the window casing you need it to be at least 7cm deep for flush track mount (this is where the headrail lines up with the window frame and the blind slats jut out slightly) or 9.5cm deep for a flush slat mount (where the slats line up flush with the window frame)

  1. Measure the depth of the window casing to ensure it’s big enough.
  2. Measure exact window width in three places (from frame to frame) – at the top, middle, and bottom. Use the narrowest width.
  3. Measure exact window height in three places (from the top of the frame to the sill) – in the middle and to the left and right. Use longest height.
  4. Measure the window diagonally in two places from top left to bottom right corner and top right corner to bottom left. If the two are not equal you will need to go for an outside mount.

Outside mount

  1. Measure the exact width of window including the frame and add about 7.5cm to each side for light control and privacy.
  2. Measure the exact height of window from the top edge of the frame to the bottom edge, or to top of sill if there is one. Add about 7-8cm above the window to allow for mounting area.
  3. If the vertical blinds are to be floor length measure as in step two but deduct a cm or two so the slats don’t touch the floor.

Vertical blinds stack options

One-way draw (when all the slats pull to one side) – measure the width of the window including the frame and add 7-8cm

Russells blinds

Roller blinds

Inside mount

  1. Measure the depth of the window casing to ensure it’s big enough.
  2. Measure exact window width in three places (from frame to frame) – at the top, middle, and bottom. Use the narrowest width.
  3. Measure exact window height in three places (from the top of the frame to the sill) – in the middle and to the left and right. Use longest height.
  4. Measure the window diagonally in two places from top left to bottom right corner and top right corner to bottom left. If the two are not equal you will need to go for an outside mount.

Outside mount

  1. Measure the exact width of window including the frame and add about 7.5cm to each side for light control and privacy.
  2. Measure the exact height of window from the top edge of the frame to the bottom edge, or to top of sill if there is one. Add about 7-8cm above the window to allow for mounting area.

Be cautious and precise

We cannot stress enough how important it is to be extremely precise with your measurements. Even the smallest miscalculation could have quite noticeably negative results. With Russells, our style consultants know exactly how to take measurements and have a lot of experience doing so. They will take correct measurements of your window when they visit you for you in-home consultation.

Everything you need to know to make the right choice for your home

GET YOUR FREE COPY NOW
Join our Style Club

Sign up and create a home you love with expert decor tips, seasonal solutions, the latest trend inspiration, exclusive offers and more.