Deck the Halls With DIY Shutters!

How to Measure for an Inside Mount Shutter

Do I have the right style of window for an inside mount?

To measure and fit inside mount shutters, your window will need to sit within a recess. Also known as a reveal, the recess is the distance between the windowpane and the edge of the wall which the window sits within.

You should have at least 60mm of clearance between any protruding window furniture and the front edge of the recess opening. 

Which frame should I choose?

You can choose and L frame or a Z frame for an inside mount: 



Important: Measure the recess where you plan to fit the frame. You should also measure the front of the opening to ensure the assembled frame can fit through.

The L Frame can be fitted anywhere within the recess, as long as there is enough clearance for the slats to tilt without fouling the window or any window furniture (e.g. handles, locks or vents). 



The Z Frame must be fitted at the front of the recess. The Z frame is a great option which allows the panels to fold back 180 degrees against the interior wall. It also has a lip which can cover gaps caused by uneven walls.

Important: Our Z frames come pre-adapted to allow for protruding window sills

What do I need?

  • A good quality steel tape measure
  • A spirit level
  • Pen and paper

How do I measure?

Step 1: Measure the width
Measure the width at the top, middle, and bottom of the recess then select the smallest measurement.

Step 2: Measure the height
Measure the height on the left, middle and right of the recess then select the smallest measurement. To measure the height for a café style shutter, measure from the bottom up to where you’d like the finished height of the shutter to be.

Step 3: Apply deductions 
Reduce the smallest width and height measurement by 4mm, these are the sizes to use when you order. 


If there are picture rails, skirting boards, or a kitchen upstand within the recess, you may remove them. Or, if left in place, remember to measure in between these items to find your smallest recess width.
If you have an inwards opening window, please check this page for advice on how to measure shutters for this style of window.
For extra help with measuring, our frame templates can be downloaded Here

How Do I Design My Shutters?

Once you have your measurements, it is time to consider the design options for your shutters. Keep your tape measure handy as this may be needed when choosing your design.

Full Height – Style Guide
Café Style – Style Guide
Tier on Tier – Style Guide
Ready to start configuring your shutter? Click here to shop our window shutter styles.
Our team are always happy to offer design advice and measuring tips. Simply email a photo of your window to and we will get back to you with our helpful suggestions!