Improved Roof Surfaces

The Actueel Hoogtebestand Nederland (AHN) is a dataset containing detailed and highly accurate height information for the entire Netherlands. Using laser technology, 3D elevation data has been collected from helicopters and airplanes. This means the ground elevation of every square meter in the Netherlands is known with an accuracy of up to 5 centimeters. The AHN also includes information about buildings, obstacles, and vegetation.

In the new year, Quickr Scan and the Design App will start using updated AHN4 data, allowing you to benefit immediately from the higher accuracy and freshness of this data. We have also improved our algorithms to further enhance your experience.

Previously, the system relied on AHN3 data, but starting now, AHN4 will be used. Below are the main differences between AHN3 and AHN4:

Shorter data collection period:

• Measurements for AHN4 were carried out between 2020–2022, compared to AHN3’s period of 2014–2019, making the data more up-to-date.

Higher point density:

• In most areas of the Netherlands, AHN4 has a point density of 10–15 points per square meter and in urban areas (like the Randstad), this increases to 20–25 points per square meter. In comparison, AHN3 had 6–8 points per square meter. This higher density makes smaller details more visible.

Minor changes in point cloud classifications:

• These changes are mainly noticeable for users working directly with the point clouds (LAZ files). If you work with the grids (DTM or DSM), this change is minimal or barely noticeable.
  The primary benefit of AHN4 is the improved accuracy of roof surface measurements, which means layout plans will be more precise. This is because AHN4 uses a source with double the resolution —increasing from 50 cm resolution in AHN3 to 25 cm in AHN4.

Another benefit is that roof surfaces will now align much better with the 2020/2021 aerial photography in many cases. This improvement is possible thanks to the updates we’ve made to our algorithms.

In the image below, you’ll see three colored areas. The data for the green and blue areas is already available in AHN4. The black area, however, will still use AHN3 until mid-April, when AHN4 data will become available.

Request a Demo
See these features in action! Request a demo today, completely free of charge and with no obligations.