From Bricks to Digital: Teleki-Bolyai Library's Scan to BIM Survey

5000 m2
2024

The importance of Teleki Téka

The Teleki Téka, also known as the Teleki-Bolyai Library, is one of the outstanding cultural heritages of Targu Mures. The library founded in 1802 by Count Sámuel Teleki preceded even the establishment of Budapest’s first public library. At the start, the collection had more than 40,000 volumes, which were further expanded over the years. The institution was taken over by the state after 1945, and in 1955 it was merged with the library of the Reformed College, thus enriching its previously unparalleled collection with more than 80,000 volumes. Due to the building’s history and cultural values, the library plays a key role in the preservation of both Transylvanian and Hungarian cultural heritage.

The history and architecture of the building

The building is from the 17th-18th century. It was built in the Baroque style at the turn of the century and evokes the atmosphere of small castles in Transylvania. Sámuel Teleki added the western wing, which was completed in 1802, thus acquiring the shape we know today. Over the years, the building has undergone many modifications, the wing facing Borsos Tamás street was especially affected by these modifications.

The challenges of architectural surveying

Our client, NM Studio, was tasked with the architectural design of certain areas of the building. Their workflow is based on BIM, that is why a scan to BIM approach was necessary for the architectural survey. The last survey was made more than twenty years ago, and until now no accurate LiDAR survey or BIM model of the listed monument building has been made. Before the scanning, our team also asked for an expert opinion from an art historian in order to better understand the cultural values of the building and to pay special attention to precision in the appropriate areas. This is how we found out for example that due to the repeated reconstruction of the aforementioned Borsos Tamás street wing, irregularities of a few centimeters in the wall thickness can have significance. As a result, we measured these areas even more carefully.

Precise survey with LiDAR technology

The millimeter precise scans resulted in a point cloud that was created in full color. We used both static and mobile scanners to effectively cover different types of spaces. The static scanner was used in areas needing the highest precision or tight spaces, such as the attic and basement, creating the frame or skeleton of the point cloud. The mobile scanner was used in larger, more accessible or more detail-rich areas. When scanning the attic, we deployed both devices and recorded the frame of the measurements with the Leica BLK360, while the BLK2GO recorded the details of the wooden roof structure from all angles faster.

During the project, we also created a walkable and VR compatible version of the point cloud that can be viewed by anyone with the free point cloud viewer software by Leica: TrueView – watch our presentation video for yourself!

Photogrammetry and value registry

In addition to the traditional LiDAR survey, we also used a photogrammetry solution, allowing anyone to view online the only remaining Baroque stove, the stone-carved mermaid door frame, and the walls of the frescoed hall. This method provides an interactive experience for visitors, who can study the details of the building more closely.

The use of advanced photogrammetry techniques allowed us to accurately position complex details within the model, ensuring a high level of precision and detail.

Creating a BIM model

The BIM model is a digital twin of the building that can contain all information related to the building. It is used throughout the entire lifecycle of the building, from design and execution to operation. During the project, we prepared a precise, detailed and trustworthy BIM model of the building, including the roof structure, with a margin of error of only a few centimeters in 3D space. The point cloud served as the basis for the model.

This approach provides greater precision than any other survey technique currently available, surpassing even topographic or geodetic approaches. The data imported in the model can be viewed as a 3D model, 2D drawings, or even lists of elements, such as a list of windows and doors, structural elements or any other elements.

Results and significance of the work

Our team is proud of the work done, which contributes to the preservation and the future renovation of the Teleki Téka library, an important part of our built heritage. The results of the project enable a more thorough study of the library and the building, its preservation, and the maintenance of the valued building throughout its whole lifecycle. The creation of the LiDAR survey and the BIM model not only helps the design process, but also plays an important role in preserving the historical and cultural values of the building, so many more of the coming generations will be able to experience it.

The survey and modeling of Teleki Téka is an example of how modern technology can be used to preserve and present our cultural heritage while enabling a wider audience to get to know them more deeply. This is one of Vertex Pavilions’ most important values: preservation through digitalization.