How Ressort Wonen commissions hybrid NEN2767 inspections to increase quality

In this customer case, we focus both on a specific project that we carried out for Ressort Wonen and the long-term cooperation between Ressort and supRmen. Here we elaborate on the challenges around implementation at the organizational level, the impact of using 3D models on daily processes and future cooperation.

‍

We zoom in on a maintenance inspection of two complexes on the Essendaal (shaded green) in Rozenburg. After previously completed projects, Edmond Boumeester, coordinator of planned maintenance and projects at Ressort Wonen, saw many opportunities for these complexes to use a digital photorealistic 3D model for inspection. This project served as a pilot of the collaboration between supRmen and Raderadvies.

‍

This high-rise complex with over 100 homes is difficult to inspect in the traditional way. Because of the height and the fact that the complex borders water, parts of the exterior facade are difficult to reach. Even with the use of an aerial platform, the back side would be inaccessible for further inspection at height due to vegetation and water. This ensures that with a traditional inspection, large parts cannot be inspected, making the NEN2767 report and the MJOB less complete than desired. Edmond Boumeester wanted more control over this. The question to supRmen was therefore: "Can you offer a solution with which we can determine the quantities, dimensions and condition measurements of this complex, which is difficult to inspect, accurately by means of a 3D model as a basis for the budget?

Our solution consisted of four phases:

1. Gathering all images of the complex;
2. Visualizing these images into a photorealistic 3D model;
3. Quantifying numbers, dimensions and defects;
4. Conducting an inspection

Gather

Informing residents and neighbors

We have started informing all residents and neighbors within a 50-meter radius of the building by means of a comprehensive letter about the work to be performed using drones. People and car license plates are automatically blurred by our algorithm, so there is no invasion of privacy. This can be compared to Google Streetview.

‍

Implementation on site

Implementation starts with measuring base points. These are crucial to accurately determine dimensions and deviations. Next, we took about 3,000 photos of the complex. These photos were taken with high resolution cameras (100MP) from the air as well as from street level. In this way, even undersides of balconies were captured razor-sharp and accurate. Areas such as roofs and high facades that would normally only be reachable with an aerial platform were also accurately captured.

Gathering all the images took a day and a half. The images were taken with a detail level of no more than 2 millimeters deviation, so that the elements and quantities could be accurately determined and there was so much detail in the model that the condition could also be determined.

‍

Visualize

All photos taken by the drone and at the street level were stitched together into a complete online photorealistic 3D model in our cloud-based platform, in which all details were visible in 2D and 3D.

We collected all appointments, execution activities, documents and other information in a central place in our customer portal. This made all information centrally visible in one place and everyone was always up-to-date on the progress of the project.

‍

Quantify

All data of the complex were extracted from the 3D model and converted to directly applicable information. This includes elements and quantities, as well as dimensions and defects that are visually visible.

Inspect

When determining the conditions of the roof and facades, desk condition scans are performed by one of our partners on the photos and 3D models taken. These desk condition scans are combined with a site visit. Before this desk condition scan is performed, supRmen names all roof surfaces and elements for the purpose of traceability. With this, all numbers and dimensions are also known.

Desk condition scan reports cover the main defects and accompany them with relevant photographs. In this project, the condition scans were performed by Raderadvies.

This hybrid form of inspection offered the best of both worlds. As mentioned earlier, the 3D model allows otherwise inaccessible places to be inspected, increasing the inspector's sample size. This allows the extent of the defect to be better determined and also reveals defects that otherwise would not have been noticed. An example of this is the floor finish of the balconies. These were found to be good on site, but drone images and the 3D model showed that they were in worse condition at other balconies.

‍

Beyond the advantages offered by the hybrid form of inspection, all data obtained is more widely applicable. The result of the solution provided;

A NEN2767 report based on a hybrid recording (physically on site and from the 3D model) which makes the sample of inspected parts much larger.

Access to accurate data; smallest details and precise conditions were visible.

Short term large amount of photos and 3D images of the roofs and facades to be used as archives and reference work.

Added value for the inspector to increase the quality condition measurement of hard to reach areas. This can be done prior to the site visit which makes the visit more focused and thus more efficient. The additional benefits

‍

In addition to the results that directly address the problem Ressort Wonen had, there are additional benefits, namely;

Overview of numbers and dimensions of all building elements including high-quality images of these elements.

Reducing visits to residents, such as to look on the balcony.

Possibility of periodic recordings and trend monitoring, allowing insight into degradation.Integral solution; models can be used for multiple purposes.