Frequently asked questions about window measurements

Introduction

Accurate window measurements are a crucial step when ordering PVC windows and blinds. Incorrect sizes lead to delays, rework and extra costs. This guide answers common questions about measurements, explains which dimensions manufacturers need and when to call a professional measurer.

What is measured during an inspection

• Width and height of the opening measured on the inner reveal.
• Depth of the window sill if it affects installation.
• Distance to nearby obstacles (sockets, structural elements).
• Presence of ledges, niches or irregular surfaces.

Note: For production, manufacturers typically need three main measurements: width, height and installation depth, but an on-site inspection reveals specifics.

How to measure correctly — step by step

1. Prepare a tape measure, spirit level and a notepad.
2. Measure the width in three places: top, middle, bottom — use the smallest value for the order.
3. Measure the height in three places: left, center, right — again take the minimum.
4. Check the diagonals of the opening to detect skew or deformation.
5. Measure the reveal depth and distance to obstacles.
6. Record all values and take photos of the opening.

Common mistakes when measuring yourself

• Taking only a single measurement instead of three — leads to inaccuracies.
• Ignoring wall and reveal irregularities.
• Incorrectly measuring sill depth.
• Not checking diagonals — an opening may be trapezoidal.

If you are unsure about accuracy, call a specialist: a professional measurer considers thermal bridges, ventilation and required installation gaps.

Measurements for different window types

• Balcony and loggia blocks: consider the threshold and finishing details.
• Arched or non-standard shapes: a measurer creates a template and captures extra dimensions.
• Cassette and panoramic windows: measures include load and fixing method.

When to call a professional measurer?

• For non-standard openings, curved walls or older buildings.
• If you plan insulation or interior finishing after installation.
• When ordering blinds or roller shades that require precise fabric dimensions.

Frequently asked questions (FAQ)

Should I measure the window myself?

If the opening is simple and rectangular you can take preliminary measurements. For a final order we recommend a professional measurement.

What installation clearance should I leave?

Manufacturers usually allow a 10–20 mm installation gap in width and height for foam and alignment.

What if the diagonals differ?

This indicates an uneven opening. In such cases, the window is made smaller and adjusted on site.

How to account for a sill and trim?

Measure from the surface where the frame will be fixed. If the sill is part of the order, measure its depth separately.

Are photos necessary?

Yes, photos help spot complex areas and speed up coordination when ordering.

How long does a professional measurer take?

Typically 20–40 minutes for a standard window, up to an hour for complex or custom solutions.

Conclusion

Accurate measurement ensures proper installation and long service life. If you have any doubts, contact DK-Logi specialists: we will perform measurements, recommend profiles and advise on maintenance and finishing options.