How 3D Scan to Revit Can Solve As-Built Modeling Challenges

Scan to Revit BIM models transform As-Built modeling by documenting precise real-world conditions. This removes inaccuracies caused by traditional methods and enables effective renovations, retrofits and facility management. Seamless clash detection and Quantity Takeoffs (QTOs) save costs and time to enhance project results.

As-Built modeling plays a significant role in construction and renovation by providing precise and information-rich documentation of existing buildings. This supports renovation planning, retrofits, and facilities management efficiently. Accurate As-Built models help architects, contractors, engineers, facilities managers, surveyors, and laser scanning companies plan effectively and reduce costly errors during construction and renovation. However, legacy methods of creating these models lead to inaccuracies, missing data, and slow manual work.

When integrated with Revit, 3D scanning technology, particularly through point cloud to BIM conversion, provides a robust solution to resolve these obstacles. This article explores the capabilities of 3D scanning and Point Cloud to BIM workflows to enhance the accuracy and efficiency of As-Built modeling, transforming processes for surveyors, laser scanning firms, and construction professionals for improved project planning and execution.

The Importance of Accurate As-built Modeling

Precise As-Built models are the foundation of successful construction and renovation. They provide a detailed depiction of the existing state of a building or structure, which is important for multiple reasons:

• Project Cost and Timeline: Errors within As-Built models create issues during construction and renovation, which lead to schedule and cost overruns. Accurate As-Built models ensure everything within the project is planned from the start.
• Compliance and Safety: Adherence to building codes and safety rules within As-Built models ensures occupant safety and the better performance of various building systems and equipment. Issues within these models result in violations that are costly to fix and compromise building safety.
• Renovation and Retrofits: Renovation projects rely on a thorough understanding of existing structures. Precise and data-rich As-Built models aid architects and engineers in making seamless changes within the current building.
• Facility Management: As-Built models are important deliverables for ongoing facility management, serving as a roadmap for maintenance activities, renovations and necessary upgrades.

Though important, legacy As-Built modeling methods fall short of delivering the required accuracy. That’s where 3D scanning provides a robust solution that is precise and timesaving.

What is 3D Scanning?

3D scanning is a technique that utilizes specialized devices to document the physical features of a space or object to create precise 3D models called point clouds. These point clouds are made up of millions of data points that accurately depict the size, shape and arrangement of building elements within the scanned space.

Types of 3D Scanners

• LiDAR (Light Detection and Ranging) Scanners: LiDAR scanners employ laser beams to measure the distance between the surrounding objects and the scanner. These scanners are precise and gather data from vast spaces, which makes them suitable for scanning indoor and outdoor spaces in complex projects.
• Photogrammetry: Photogrammetry generates 3D models through the use of images taken from multiple perspectives. Although not as accurate as LiDAR, it’s a cost-friendly option for objects and projects on a smaller scale. Photogrammetry is easier to access, since it can be performed with drones and digital cameras.
• Terrestrial and Mobile Scanners: Terrestrial scanners are used to scan larger areas, while mobile scanners are attached to vehicles or handheld to capture data while moving. The choice between the two depends on the specific requirements of the project.

Advantages of 3D Scanning over Traditional Methods

• Higher Accuracy and Precision: 3D scanners collect large amounts of data with high accuracy, surpassing the precision achieved through manual measurements.
• Speed and Efficiency: Scanning is considerably quicker than manual measurements, leading to expedited project completion.
• Complex Geometries and Hard-to-Reach Areas: 3D scanners can document minute details and measure areas that legacy tools struggle with or fail to reach, such as complex building facades and high ceilings.

How 3D Scanning Integrates with Revit for As-built Modeling

Combining 3D scan data with Revit has transformed the process of As-Built modeling to create a smoother transition from data capture to the generation of a 3D model.

Overview of the 3D Scan to Revit Process

• Capturing Data: The process starts by scanning the building or site using a 3D scanner. Based on the project’s needs, several scans are taken from multiple perspectives to capture the necessary details.
• Processing Scan Data: The unprocessed scan data is converted into a point cloud. This involves connecting multiple scans, removing errors and ensuring the data reflects real-world conditions.
• Importing Point Clouds into Revit: After preparing the point cloud, it is imported into Revit. Using Revit’s tools, the point cloud is scaled and oriented accurately to mirror real-world conditions.

Working with Point Clouds in Revit

Scan Model

3D BIM Revit Model

• Conversion to 3D Models: Within Revit, point cloud data is transformed into detailed 3D models. Revit’s Point Cloud tools help with the creation of precise geometry by tracing the point cloud and extracting elements like floors, walls, ceilings and structural members.
• Creating Accurate As-built Models: Revit allows for the creation of accurate As-Built models by letting designers overlay designs on top of the point cloud, which ensures that every detail is documented perfectly. This is helpful for creating intricate shapes that would be difficult to model using manual techniques.
• Using Revit’s BIM Features with Scan Data: Revit’s BIM capabilities enable the combination of scan data with a holistic project model. This point cloud to BIM model can be used to identify clashes, coordinate the model and generate thorough construction documents.

Advantages of Using Revit with 3D Scans

• Seamless BIM Integration: Revit’s BIM tools offer a unified platform to track every project phase, from the initial design to the finished construction. 3D scan data becomes a part of this process that assures absolute precision.
• Enhanced Accuracy and Detail: Integrating 3D scanning with Revit results in As-Built models that are accurate and detailed, reducing the chances of errors during construction or renovation.
• Improved Project Collaboration: Revit’s features that enable collaboration, such as cloud storage and shared models, improve communication and teamwork between project teams. This ensures every project participant is aligned with project needs.

Key Challenges in As-built Modeling Solved by 3D Scan to Revit

Combining 3D scanning with Revit addresses major issues within as-built modeling. It offers effective and streamlined solutions.

Success Stories of 3D Scan to Revit in As-built Modeling

Scan to BIM modeling for a 16th monument in the UK leads to precise renovation timelines.

A laser scanning services provider from the UK approached Hitech CADD Services for the Scan-to-BIM conversion of a monument building. Using 3D survey measurements and survey images, the team at Hitech CADD Services generated a Scan-to-BIM Revit As-Built model at LOD 400. The final deliverables helped the client to:

• Obtain a documented and digitized copy of the heritage structure
• Gain insights into manpower costs and accurate material quantities
• Accelerate renovation timelines

Scan to BIM Conversion

BIM Revit Model

Point Cloud to Revit

3D View

Point cloud to BIM modeling for a retail coffee outlet in the US helped the client with improved facilities management.

Hitech CADD Services were contacted by a surveying firm from the US regarding a retail coffee outlet. Point cloud to As-Built Revit modeling services were required to create an As-Built Revit model for better facility management. Using Point cloud data drawings, scans and 360-degree photos provided by the client, the team at Hitech CADD Services created an As-Built 3D Revit model with 10 mm accuracy. The final deliverables, including building sections, floor plans, site plans, and roof plans, led to:

• The creation of the Revit model and As-Built drawings was handed over ahead of schedule.
• Improvements in building assessment with an accuracy of +-10 mm.

Exterior Details

Revit 3D Model Converted from Scan Data

Future Trends: The Evolution of As-built Modeling with 3D Scanning and Revit

The future of As-Built modeling shows substantial progress, driven by developments in 3D scanning tools and improvements in Revit features.

Advancements in 3D Scanning Technology

• Increased Accuracy and Speed: Upcoming 3D scanners are poised to deliver higher accuracy and accelerated data collection, which makes them more suitable and efficient for larger projects.
• Miniaturization of Scanning Devices: Building smaller portable scanners would make it easier to access hard-to-reach areas and challenging environments, thus extending the scope of 3D scanning.

Revit’s Future Capabilities

• Enhanced Tools for Handling Large Point Cloud Datasets: Revit is anticipated to become more efficient at handling and working with vast datasets, which would simplify the process of working with detailed point clouds.
• Improved Collaboration Features: With the increasing popularity of cloud-based model sharing, Revit is expected to enhance its collaboration features, enabling real-time model updates and more effective teamwork.
• Real-time Scanning and Modeling Integration: Integrating live scanning directly with Revit would enable model updates in real time as modifications occur on the construction site, making the process even more accurate.

The Role of AI and Machine Learning

• AI-assisted Object Recognition: AI has the potential to significantly expedite the modeling process by identifying and classifying objects within point clouds, thus mitigating the need for manual intervention.
• Automated Clash Detection and Resolution: Machine learning algorithms could automate the process of identifying and resolving clashes within models to assure that As-Built models are error free.
• Predictive Modeling for Maintenance and Future Renovations: AI has the potential to analyze As-Built models and predict potential maintenance needs and future renovations, leaning toward a more proactive building management approach.

Conclusion

Combining 3D scanning with Revit has transformed As-Built modelling, bringing significant benefits for surveyors and the construction industry alike. By identifying and resolving issues like inaccurate measurements, time-consuming processes, and the challenges of capturing complex shapes, these technologies ensure accurate, comprehensive, and efficient 3D modeling. As technology advances, we can anticipate even more precise and powerful As-Built modeling, which will benefit construction and renovation. Embracing these technologies will boost project success, mitigate errors, and ensure high-quality As-Built models.

FAQs

Nirav Vyas is a BIM Manager at Hitech CADD Services and has over 14 years of experience in the AEC sector. His innovative approach to Revit Dynamo automation has led to successful completion of various commercial and residential projects in Netherlands, Belgium, Turkey, US, Germany, Dubai and Oman. Nirav’s primary focus is to automate client workflows and processes, while looking for ways to enhance business productivity through BIM automation.