3D Laser Scanning and CAD Reconstruction of a Sawmill – Digital Basis for a Retrofit Project
Initial Situation
For the planning of a comprehensive retrofit project in an existing sawmill operation, a reliable digital as-built basis was required.
The existing building structures had evolved over time and were not available in up-to-date technical documentation.
For planned modifications, extensions, and the integration of new plant equipment, geometric information was needed—particularly for load-bearing structures, roof geometries, traffic areas, and machine environments.
Conventional survey methods are of limited use in such facilities: complex geometries, restricted access areas, and large spatial dimensions make manual measurement time-consuming and error-prone.
For this reason, a complete 3D laser scan of the facility was commissioned, including the digital reconstruction of all relevant building elements.
Scope of Services
The project consisted of several coordinated work phases:
On-Site Laser Scanning
The on-site scanning was completed within two days. The following areas were captured:
- Building envelope
- Roof structures
- Production halls
- Traffic and storage areas
- Structurally or functionally relevant interior zones
The scan data was provided as a point cloud in E57 format, supplemented by a viewer for direct visual inspection.
Data Processing and Cleaning
The point cloud was cleaned, filtered and segmented for further processing and modelling within the agreed project requirements.
CAD Reconstruction in HiCAD / HELiOS
Based strictly on the scan data, the following elements were reconstructed:
- Main building geometry
- Roof landscapes
- Concrete and foundation areas
- Relevant geometries in proximity to machinery
- Section planes, reference levels, and planning axes
The modeling process was carried out with iterative coordination with the client’s project team.
Data Exchange and Project Integration
Collaboration was handled via a shared cloud workspace. The delivered data included:
- STEP files
- PDF views
- Updated CAD models reflecting design changes
- Supplementary screenshots and technical evaluations
Feedback cycles were managed through written markups, phone calls, and online meetings, allowing changes to be implemented efficiently.
Final Deliverables
The final project output included:
- A fully usable STEP model (~182 MB)
- Point-cloud datasets for the surveyed areas
- Viewer files
- Structured project documentation
These datasets now form the basis for retrofit planning, interface construction, and subsequent plant integration.
Project Challenges
- Large and complex building structures
- Varying ceiling and roof heights
- Highly confined and difficult-to-access areas
- Lack of existing as-built documentation
- Tight geometric tolerances required for selected steel-construction and plant-engineering tasks
According to the project record, scanning captured the areas included in the agreed scope and was completed without significant disruption to ongoing operations.
Client Benefits
- Precise geometric data as a reliable planning foundation
- Significant time savings compared to manual surveying
- Reduced risk through planning based on verified as-built data
- Direct usability in CAD, 3D engineering, and BIM workflows
- Structured digital documentation for future planning
Conclusion
By combining 3D laser scanning, point-cloud processing and CAD reconstruction, the project produced digital reference data for retrofit planning at an operating sawmill.
The delivered data supported planning and coordination between project disciplines. Further design and construction decisions remain subject to project-specific checks and site conditions.
The survey and model provided a reference for the planned retrofit work.