When ordering a new window or door, it is very important that you enter the correct measurements at the very beginning, meaning the exterior measurements of the window/door frame (width x height). First, measure the width and height of the intended opening for the product, measure the width from reveal to reveal and the height from the windowsill/lower reveal to the upper reveal (a windowsill profile with a height of 30 mm is added to the edge beneath the PVC windows and balcony doors).
Once you have obtained the measurements for the opening, subtract 30 mm from both results, this will leave the necessary installation and insulation space of 15 mm around the product. In case the window or door is non-opening, then measure the division of the product into parts, measuring from the outside edge of the frame to the middle of the dividing pillar.
