How to measure correctly

How to measure window frames correctly

To ensure your moldings fit perfectly, we need the inner dimensions of your window frame. Simply follow these 4 steps.

Step 1: Where to measure?

The moldings are attached to the inner frame of the window, directly in front of the so-called stop edge.

  • Open the window and locate the edge where the sash rests when closed.
  • Place your tape measure exactly in front of it on the inner frame (see yellow markings in the image).
  • Important: Measure each sash individually, as old windows are often not perfectly square.
Window frame with yellow marking
Folding rule measurement on the frame

Step 2: Measuring the height (The trick)

To determine the exact inner dimension without the folding rule getting in the way, we use a trick:

  1. Measure from the top corner to approx. the middle and make a small mark at a round number (e.g., 40 cm).
  2. Then measure from the bottom corner to this mark.
  3. Add both values (e.g., 40 cm + measured lower value).

This is your exact height measurement. Repeat this on the opposite side.

Step 3: Measuring width & minding the meeting stile

With double windows, two sashes often meet in the middle (meeting stile). Since the molding cannot run continuously here, this area must be left out.

  • Close the sash and mark with a pencil at the top and bottom where the meeting stile begins and ends.
  • Now measure from the left inner frame to your pencil mark.
  • Repeat this for the right side (from the right frame to the mark).
Measuring the width on the window frame
Enter values into form

Step 4: Enter values

You have now collected 6 measurements (3 for the left, 3 for the right).

After your order, you will automatically receive a form from us via email. There you can enter these values and name each window (e.g., "Kitchen") so you know exactly which molding belongs where during installation.