How to Measure Your Window Opening for Hassle-Free Installation

Accurate window measurements are key to ensuring a smooth and cost-effective installation process. While initial dimensions can be provided by the client, only a professional measurer can determine the precise scope of work. This guide provides step-by-step instructions for making initial measurements of your window opening, whether it features a quarter or not.

General Measurement Tips

  • Measure both inside and outside the building to account for variations in wall depth.
  • Walls are often uneven, so take measurements at the top, middle, and bottom. Use the smallest measurement for accuracy.
  • Account for the installation gap, which ensures easy fitting and compensates for extreme temperatures.
  • Draw a simple sketch of the window and label the dimensions for clarity.

Measuring a Window Opening Without a Quarter

  1. Width: Measure the distance between the left and right sides of the opening at three points. Use the smallest value and subtract 20-40 mm for the installation gap.
  2. Height: Measure the vertical distance at three points. Subtract 15-20 mm for the top installation gap and 30 mm for the base profile.
  3. Sill & Drip Edge:
    • The windowsill width should fit without obstructing the radiator.
    • The drip edge should extend 30-50 mm beyond the wall.

Measuring a Window Opening With a Quarter

  1. Width: Add 40-60 mm to the width of the external opening to allow the frame to extend behind the quarters. Ensure this does not exceed the internal slope width.
  2. Height: Measure from the base to the top slope. Subtract 10-20 mm for the bottom gap, 30 mm for the subframe profile, and add 20 mm for the frameโ€™s extension over the top quarter.
  3. Sill & Drip Edge: Measure similarly to non-quarter openings, considering the projection and attachment points.

Why Accurate Measurements Matter

Professional measurements prevent costly adjustments and ensure your window fits perfectly. While this guide helps with initial sizing, consulting an expert is essential for flawless installation.