How to Measure a Caravan Window Cut-Out

Replacing or fitting caravan windows isn’t difficult, but it starts with one step you can’t overlook: getting the cut-out size right. A mis-measured window can lead to leaks, rattles, or ordering the wrong product. This guide shows exactly how to measure a caravan window cut-out so you can order with confidence.

What is a Caravan Window Cut-Out?

The cut-out is the raw opening in the caravan wall where the window frame sits. Unlike the overall frame size, the cut-out measurement is the true size of the hole in the wall. Suppliers base their sizing on this cut-out, so it’s the number you must get right.

Step 1: Expose the Opening

Remove the inner frame screws from the existing window.
Gently push the window unit out from the inside.
Clean off any sealant or butyl tape around the opening.

You should now see the raw cut-out in the panel.

Step 2: Measure the Opening, Not the Frame

Measure the width across the top, middle, and bottom.
Measure the height on the left, centre, and right.
Caravan walls aren’t always perfectly square, so take multiple points.
Record the smallest width and height as your true cut-out size.

Step 3: Record in Millimetres

Caravan window sizing is in millimetres.
A “550 × 700” window means a 550 mm high × 700 mm wide cut-out.
The overall frame will be larger, but the cut-out is what matters for ordering.

Step 4: Check Wall Thickness

Measure the wall depth at the cut-out. Common sizes are 25 mm, 30 mm, or 45 mm.
Choose a window kit that matches the wall thickness so the inner frame clamps correctly.

Step 5: Confirm Before Ordering

Measure twice and write the numbers down.
If you’re between sizes, ask your supplier about trims, fillers, or custom options.
Ordering slightly too small is usually easier to manage than too large.

Tips & Common Mistakes

Don’t measure the glass or acrylic pane.
Don’t round off your measurements.
Take a clear photo of the opening with a tape measure visible.
Check for obstructions behind the wall before enlarging any opening.

Why Accurate Measurement Matters

A correct cut-out means a clean, watertight fit, less chance of rattles, and no headaches with returns or freight back-and-forth. It’s the quickest way to a pro finish.

Next step
Once you’ve confirmed your cut-out size and wall thickness, choose a window that matches. We stock a wide range of caravan windows with integrated blinds and flyscreens in multiple sizes, designed for easy installation and Australian conditions.

Shop caravan windows with blinds & flyscreens at VanDIY