Saint-Nom-de-Marie Church
Client / Collaborator
Nadeau Blondin Lortie Architectes
Sector
Architecture, Patrimoine, Culturel, Religieux
Location
Marieville
Services
Relevé LiDAR, Relevé par drone, Photogrammetrie, Dessins CAD
Mandate
As part of the digitization project for the Saint-Nom-de-Marie Church in Marieville, the architects needed accurate documentation of the building's current condition to better understand the visible deformations, cracks in the masonry and the building's overall geometry. DGTL conducted a detailed survey to obtain a comprehensive overview of the building using a point cloud, while also producing high resolution orthoimages to facilitate the analysis of the façades, the identification of sensitive areas and the planning of interventions.
Mandate
As part of the digitization project for the Saint-Nom-de-Marie Church in Marieville, the architects needed accurate documentation of the building's current condition to better understand the visible deformations, cracks in the masonry and the building's overall geometry. DGTL conducted a detailed survey to obtain a comprehensive overview of the building using a point cloud, while also producing high resolution orthoimages to facilitate the analysis of the façades, the identification of sensitive areas and the planning of interventions.
Proposition
Control Network and Coordinate System
A control network is established to provide a robust geometric reference at the site-wide scale. Distributed throughout the exterior areas, the control points ensure spatial consistency, the alignment of different data collection campaigns, and the reliability of the data used for 3D scanning and CAD drawings.
High-Density Terrestrial LiDAR
A high-density terrestrial LiDAR survey of the building envelope is then conducted to capture the fine details of the historic facades, openings, volumes, and visible architectural elements. This step supports an accurate interpretation of the existing structure and helps preserve the geometric richness of the historic building.
Photogrammetry
A planned drone mission was carried out to capture all facades from multiple angles. The images were registered to the primary control network to produce a detailed, consistent, and usable 3D reconstruction.
Terrestrial LiDAR and Photogrammetry Hybrid
A combination of the terrestrial LiDAR survey and the photogrammetric survey was produced to create a completed, detailed and accurate point cloud.
Deliverables
High-density, High-precision and Accurate Coloured Point Cloud
Delivery of a high-density colour point cloud, generated through hybrid processing of LiDAR survey data and drone-based photogrammetric survey data, and constrained by the control network and LiDAR reference to ensure reliable geometry. This format is particularly effective for 3D documentation of historic buildings.
Façade Orthophotos at 1 mm per pixel
Facade orthophotos at 1 mm per pixel accompany the survey and allow for clear visualization of cracks, defects, joints, and stone details.
CAD Elevations
We produced detailed CAD elevations based on the digital twin, with geometry suitable for coordination and documentation. The deliverables are structured to facilitate reading, verification, and integration into workflows.
