Scan to BIM: Ultimate Guide for Point Cloud to BIM Modeling

Reconstruction or renovation projects usually present surveyors and laser scanning companies with multiple challenges related to information availability and as-built representation. Typically, in these cases, structural elements are damaged or missing, concealed or hard-to-reach, and available design records do not match the actuals. In architectural heritage monuments, slightest mistakes could mean courting a public backlash.

Adopting Scan to BIM or Point Cloud to BIM eliminates the risks that surveyors often face, including incorrect spatial analysis, design risks, and lack of visualization. Scan to BIM allows surveyors to easily navigate around architectural and structural complexities, and hard-to-reach MEP equipment.

Point cloud scans correctly depict all structures, spatial layout of elements, and as-built conditions to enable detection and diagnosis of every issue. With 3D Revit models reconstructed from point cloud data, architects and surveyors can easily resolve design clashes to ensure the sanctity of earlier architecture and project needs. But converting laser scan data to 3D models has its own challenges regarding the use of technology. Using specialized point cloud scan to BIM services ensures accuracy, data compatibility, and compliance.

What is Scan to BIM?

Scan to BIM is a process where laser scanning technology captures the exact dimensions and conditions of a physical structure, producing a point cloud with millions of data points. These point clouds are then transformed into precise and comprehensive 3D BIM models using software such as Revit. These digital models are invaluable for tasks like renovations, remodeling, and facilities management, providing a highly accurate representation of the existing structure.

Addressing Scan to BIM Challenges for Surveyors and Laser Scanning Companies

Surveyors and laser scanning companies face numerous challenges due to the lack of drawings, records, and visibility of structural elements in existing buildings. Some common challenges faced by these professionals include:

• Inaccurate spatial analysis
• Unreliable cost estimates
• Absence of visualization
• Lower estimation accuracy
• Greater design risks
• Reduction in operational efficiencies

How Surveyors Benefit from Scan to BIM Services

Scan to BIM provides an effective solution to challenges posed by legacy surveying and reconstruction methods. It offers many high-impact advantages to surveyors and laser scanning companies.

Some advantages of Scan to BIM include:

Applications of Scan to BIM across Building Phases

Tips and Tricks for Accurate Scan to BIM Modeling

Scan-to-BIM Modeling is a powerful tool to support a wide range of applications, including renovation, remodeling, and facility management of buildings. But it needs to be done accurately to achieve the required results and deliverables.

Interpreting the Point Cloud Data

Defining the point cloud file format with the right set of coordinates

• Review the point cloud scan data to resolve coordination issues
• Insert coordinates equivalent to the scan with a new point cloud position
• Set the base point based on shared coordinates
• Move the base point around the project coordinates to continue working in the original coordinate system
• Required graphical behaviours and precise Point Cloud displays can be achieved with coordinate accuracy

Align the point cloud to achieve improved mapping and consistency

• Collect multiple points to integrate scans
• Check the orientation of the scans in the local coordinate system
• Alignment and registration issues can be reduced by complementing the standard and scanned point cloud
• Extrapolate each point to retain density and direction to achieve rotational alignment
• Perform horizontal and vertical alignment after the rotational alignment is complete

Remove unwanted data from the scans to enhance scan-to-BIM performance

• Clean the noise of unwanted data from laser scans to reveal the required scan data or area
• Denoising the Point Cloud in the Recap and performing a Revit Export can help preserve the required features of the scans
• Accurate surface optimization can be achieved, and surface degradation can be removed through denoising

Compare scanned datasets with 2D plans and photos to enhance consistency, reduce RFIs, and lower rework

• Use 2D plans or 360-degree photos for comparison with the scanned dataset
• Comparison of 2D plans and 3D Point Cloud to BIM models with scan data can be used to create elevation views in the As-Built Cloud
• Integrated model concept removes errors, reduces budget and time overruns, and enhances model manipulation

Reduce large point cloud size to speed-up model processing

• Denoise the scans to remove unwanted data before running an import into Revit
• Place point cloud groups on worksets to improve file handling, visibility, and graphical override
• Break datasets into clusters and keep a copy to manipulate scanned file
• Setup a control model to define grids, coordinates, and levels for real-time modifications

Resolve building orientation to improve model accuracy and lower project duration

• Resolve orientation problems by setting accurate location based on Google Maps and True North
• Identify topographic elements through Google Earth for review and identification
• Create and identify component libraries for windows, doors, etc. to improve 3D model consistency

What are the different kinds of software used for Point Cloud to BIM Modeling?

Some popular and industry-recognized software used for Point Cloud to BIM are:

• Autodesk Revit®
• Navisworks®
• Autodesk Recap®
• Autodesk AutoCAD®
• Geomensura

Why is Revit the most preferred software to create Scan to BIM models?

Autodesk Revit is one of the most preferred tools in the AEC industry for creating scan to BIM models. It can be attributed to the various features of Revit, such as:

• Improved visualization: 360-degree visualization allows modelers to get exact information about building elements from scan data for creating BIM models.
• Multiple prototypes: Architects can directly use the model created using Revit as a base model to plan for alteration and renovation activities.
• Analysis and simulation: The Revit model can be used for further analysis and simulations of other aspects, such as energy consumption or accessibility. It can also produce 2D construction drawings and 4D construction deliverables, among others.
• Better collaboration: Revit collaboration tools help team members work in a collaborative shared model. This reduces clashes and improves coordination between stakeholders and various building disciplines.
• Precise dimensions and documentation: The scan to BIM model made using Revit is bi-directional. Even the tiniest edit anywhere in the model triggers automatic updates of every related component dimension and documentation.

How do you convert Point Cloud Data to Revit 3D models?

Point cloud data can be converted to 3D models in Revit using a sequential step by step process. Check out the video to see how to convert point cloud data to a 3D BIM Revit model.

Best Practices for Converting Point cloud Scan to BIM

Here are a few tips for improving model accuracy, enhance project visualization, gain better mapping, and reduce project time.

• Use a rational coordinate system with a base point
• Ensure precise point cloud alignment or registration
• Remove unwanted data from the scanned data
• Always compare the scanned datasets with images, pictures, or drawings
• Avoid the use of large point cloud datasets
• Check resolution of building orientation

3 Quality Check Phases for Ensuring Accurate Scan to BIM Models

Step 1

• Understanding and identification of the required BIM application to gather and analyze information. This includes the required components to be modeled, specific Level of Development (LOD), and non-geometric attributes.
• After the BIM has been built from the scanned data, it is sent for approval through a quality check.
• The quality check identifies all the required scan information and attributes are included, LOD levels are met, and all the elements are modeled to specification.

Step 2

• BIM modelers analyze various building elements in the scanned data to model accurate Scan-to-BIM deliverables.
• Recognizing and categorizing various components such as floors, walls, ceilings, etc. helps generate an accurate and clean Scan-to-BIM model.
• Various building and component geometry are checked as per BIM model requirements.
• The placement and location of building elements based on actual scans and geometry are checked and matched for greater Scan-to-BIM accuracy.

Step 3

• Dimensional accuracies based on tolerances of building components built to regulations and codes play are checked for “As-Is” BIM quality.
• Tolerance deviation is checked and minimized. For example, if dimensional tolerances are set to 10mm, it is ensured that the scanned data does not allow over 10mm tolerance deviation in a modeled element.
• If elements cannot be modeled in the required tolerances, then a non-graphical mention needs to be included for clarity and further decision making.

Structured Scan to BIM Workflows for As-built Automation

As the construction industry experiences digital transformation, embracing new tools, approaches, and data-centric workflows ensures smooth and improved project outcomes. Digital workflows and technology used for point cloud geometry extraction can enhance productivity, eliminate risks, and cut costs.

The road to complete digitization for as-built automation is a connected approach through multiple technology sequences. The information generated from recorded data is used to automate Scan to BIM projects and allow stakeholders to perform jobs efficiently and quickly. The following infographic demonstrates how Scan to BIM workflow can be optimized from initial scanning to a digital inventory of as-built deliverables.

Top Advantages of Outsourcing Scan to BIM Services for Surveying Firms

Surveying firms can unlock significant advantages by outsourcing their Scan-to-BIM needs, such as:

• Assured and reliable quality of renovation design and construction.
• Faster planning processes and low project risks.
• Minimal errors in quick decision-making and project modifications.
• Higher project sustainability.
• Greater long-term cost savings.
• Quick communication, clarity, and collaboration in a Common Data Environment (CDE).

Conclusion

Scan to BIM will extend its horizon through the integration of various processes and tools. It is changing the way contractors, surveyors, architects, and other professionals, approach design, construction, and renovation. Connecting processes, people, data, and tools, Point Cloud to BIM will transform existing workflows to eliminate higher costs, and lengthy schedules, and deliver quality. AI and ML will continue to enrich the point cloud scan to BIM process by identifying scanned datasets to create high-performance 3D models.