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How to measure for window shutters

Whether you’re measuring shutters for bay windows, patio doors, or standard windows, it can seem a bit daunting. Luckily, our friends at California Shutters have got you covered. Below, they’ve given us a quick run through on how to fit your own shutters, but if you’d like more in-depth instructions, check out the measuring guides on their website.

Tools for the job

Do you have a bay window or a standard window?

The type of window you have will impact how you measure for your shutters. It’s important to clarify this first before you begin. A bay window will usually consist of a central ‘picture window’, with windows at either side. The most common types are curved bay windows, box bay windows, and canted bay windows.

Made-to-measure window shutters installed in a bay window with three panes of glass, set in a bright and airy living room space.Made-to-measure window shutters installed in a bay window with three panes of glass, set in a bright and airy living room space.Made-to-measure window shutters installed in a bay window with three panes of glass, set in a bright and airy living room space.Made-to-measure window shutters installed in a bay window with three panes of glass, set in a bright and airy living room space.

What is a window recess?

The recess is the space created when a window or door is set back from the interior wall in the room. It’s recommended that you fit wooden shutters inside this recess (if available) as it is the simplest to both measure and install.

Once you know what window type you have and whether you want your window shutters fitted inside or outside the recess (this is called an inside mount or outside mount) then you’re ready to start measuring for window shutters.

How to measure for interior shutters

Step 1: Choose your frame

There are 2 frame options to choose from. You can either choose an L frame, which can sit at the front, in the middle, or at the back of your window recess. Or you can choose a Z frame that sits at the front of your recess and wraps around the edge. If you are measuring for a bay window, please download the frame templates here to see how to choose the correct frame and depth.

Two different made-to-measure shutter types. One side is labelled "L Frame" and shows an L frame shutter sitting in front of a window recess. The other side is labelled "Z Frame" and shows a Z frame shutter sitting in front of the recess, wrapping around the edge for a seamless look.Two different made-to-measure shutter types. One side is labelled "L Frame" and shows an L frame shutter sitting in front of a window recess. The other side is labelled "Z Frame" and shows a Z frame shutter sitting in front of the recess, wrapping around the edge for a seamless look.Two different made-to-measure shutter types. One side is labelled "L Frame" and shows an L frame shutter sitting in front of a window recess. The other side is labelled "Z Frame" and shows a Z frame shutter sitting in front of the recess, wrapping around the edge for a seamless look.Two different made-to-measure shutter types. One side is labelled "L Frame" and shows an L frame shutter sitting in front of a window recess. The other side is labelled "Z Frame" and shows a Z frame shutter sitting in front of the recess, wrapping around the edge for a seamless look.

Step 2: Measure your recess

Simply measure the width and height of your window in 3 separate places. Then, note the smallest measurement of both the width and height. If you have tiles or a skirting board around the recess, these will have to be removed prior to installation, so this needs to be taken into consideration.

If you’d like a mid-rail, measure from the bottom of the recess to the point where you’d like the centre of the mid-rail to sit.

Similarly, if you’ve chosen café style shutters or tier-on-tier shutters, measure from the bottom to where you would like the café style or lower tier-on-tier panel to finish.

A window in a bedroom with lines illustrating where the window needs to be measured. Three vertical lines are spaced equally across the window and frame, and three horizontal lines are equally spaced across the width of the window and frame.A window in a bedroom with lines illustrating where the window needs to be measured. Three vertical lines are spaced equally across the window and frame, and three horizontal lines are equally spaced across the width of the window and frame.A window in a bedroom with lines illustrating where the window needs to be measured. Three vertical lines are spaced equally across the window and frame, and three horizontal lines are equally spaced across the width of the window and frame.A window in a bedroom with lines illustrating where the window needs to be measured. Three vertical lines are spaced equally across the window and frame, and three horizontal lines are equally spaced across the width of the window and frame.

Step 3: Deductions

Once you’ve taken your measurements, you should deduct 4mm from your smallest width measurement and smallest height measurement. This allows for manufacturing tolerance and ensures some wiggle room. You’d be surprised at how many windows aren’t completely square!

That’s it! You’ve measured your window for interior shutters!

See? We said it was easy. As a final tip, we recommend double-checking all your measurements before placing your order.

Don’t forget that California Shutters have you covered on installation too. Check out their simple installation guide and be sure to follow each step when your new shutters arrive. You’ll have them up in no time. 

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