how to measure for angled window shutters

Measuring for angled window shutters requires precision because the panels must fit the slope or irregular shape perfectly. Here’s a clear step-by-step guide for Shutter World customers or anyone planning angled or “trapezoid” shutters:

Step 1: Gather Your Tools

  • Tape measure (metal, at least 3–5m long)

  • Pencil

  • Notepad

  • Spirit level (optional, for checking squareness)

  • Paper to sketch

Step 2: Decide Mount Type

Shutters can be inside-mounted (fitted within the window recess) or outside-mounted (fitted on the wall around the window).

  • Inside-mounted: More precise measurement needed; highlights the exact window shape.

  • Outside-mounted: Less critical to get every detail, can cover imperfections.

Step 3: Measure Width

  1. Measure the top width of the window recess from left to right.

  2. Measure the bottom width.

  3. Note if top and bottom widths differ—this indicates a sloping angle.

Tip: Take measurements in three places (top, middle, bottom) and use the smallest width for the shutter panel.

Step 4: Measure Height

  1. Measure from the base of the window recess to the top at three points: left, centre, right.

  2. Record all three heights.

  3. For angled tops, the left and right heights will differ. This helps the shutter be cut to the slope.

Step 5: Determine Angle

  • If the window top slopes, measure the height difference between the left and right sides.

  • Sketch the window, clearly marking these measurements.

Step 6: Measure Recess Depth

  • For inside-mounted shutters, measure the depth of the window recess to ensure the shutter frame will fit flush.

  • Minimum depth typically 40–50mm for plantation shutters.

Step 7: Make a Simple Sketch

  • Draw the window shape with the sloping top.

  • Label top width, bottom width, and both heights.

  • Note any obstructions (handles, vents, radiators).

Step 8: Double-Check All Measurements

  • Re-measure each dimension to avoid errors.

  • Slight inaccuracies can cause shutters to misfit, especially on angled shapes.

Step 9: Share With Supplier

  • Give your sketches and measurements to your shutter company.

  • They will usually make templates or custom-cut panels for angled windows.

Extra Tips

  • If you’re unsure, take photos of the window from front-on and side-on with measurements labelled.

  • Avoid rounding up too much—shutters need precise cuts for angles.

  • For tricky shapes (triangles, trapezoids), professional measuring is often recommended.

How to measure for angled window shutters
Angled window shutters