What is Scan to BIM?

Scan to BIM involves digitizing the physical condition of existing buildings or parts of buildings, and then creating a BIM model from it. During this process, civil engineers and surveyors use laser scanners, drones, and other 3D survey tools to create an accurate digital replica of the building.

The resulting point cloud data is used in BIM software to create an accurate and detailed 3D model, which is highly useful for planning renovations, modifications, and maintenance.

Table of contents

What are the steps involved in Scan to BIM?

1. Survey

A laser beam scans all visible surfaces, creating three-dimensional coordinate points.

Ideally, starting from the bottom (e.g., the basement), we measure and “connect” the building’s corners and stairwells, establishing a fixed reference point to distribute measurement errors that inevitably arise during the process. As a result, the deviations are minimal—only a few millimeters across the entire building, regardless of square footage.

The device also takes digital photographs, allowing us to assign real colors to each point, bringing “field reality” into the office and making the task easier for processing engineers.

The scanner typically generates two types of data:

Point Cloud

The collection of points recorded during the survey, which allows the recognition of measured elements like walls, furniture, ceiling planes, mechanical elements, etc.

2. Color Images

Color images captured in 180-360 degrees from measurement positions help engineers identify elements during processing and enable “virtual tours.”

2. Processing

For static scanning, raw data is always imported into processing software, which, after a lengthy conversion, makes it ready for further processing. Steps include:

It’s important to document the entire survey process to track where we’ve been. Surveys often occur during the day when buildings are “alive,” so the survey order may need to be adjusted due to meetings, misplaced keys, or incorrectly parked cars. Without notes, identifying where the survey took place would require additional work later.

For handheld mobile scanning, this stage (due to continuous movement during the survey) is much shorter—if the building was surveyed in a single walk-through, the BIM modelers can start working with it right after export.

3. Model Building

The point cloud alone is often not sufficient for certain purposes, so a building information model must be built from it.

The point cloud, which can consist of billions of points, is imported into modeling software (e.g., Revit), where BIM modelers process it and build a precise virtual replica of the surveyed area, known as the as-built model. AI-based automation assists with this process, but the expertise of architects is still essential for achieving good results.

The modelers then assign information to the elements (e.g., for operation purposes) and deliver it for use.

overall point cloud

BIM model

section of the point cloud

section of the BIM model

What is Scan to BIM used for?

Here are a few typical construction projects where Scan to BIM delivers excellent results:

Construction monitoring and verification

The actual built structure always differs from the plan, which can cause safety risks, rework, redesign during supervision, ongoing problems, and hidden costs.

However, by measuring multiple times during construction, you can see how and when progress is made, even capturing elements that will be hidden later. This helps to decide whether errors can be corrected or if something needs to be torn down.

Technology upgrades and brownfield investments

Brownfield projects always raise many questions: How do we move the new equipment through the existing technology? How do we route the ventilation through the wall safely, without halting operations, while keeping the next expansion in mind? What pipes run along the wall, and what pipe diameters and clearance spaces should we consider?

It’s worth documenting the exact locations of concealed structures during construction to avoid unexpected costs and frustration later.

Heritage building restoration

In these cases, right angles are not exactly 90 degrees, parallels don’t meet at infinity, and door and window frames certainly weren’t made to modern standards.

For heritage buildings, capturing the original condition with millimeter accuracy is valuable in itself, and detailed documentation and visualizations are essential for high-quality restoration.

Surveying large, complex buildings, structures, systems

In industrial environments, the mechanical system is often a tangled web of pipes, some concealed, or packed so tightly into narrow spaces that traditional measurement is impossible.

The same goes for tall, uniquely structured or shaped facilities and elements. How do we measure and model a continuously winding, multi-story, narrow spiral staircase? Without measurement, later planning becomes very risky.

Of course, there are also non-typical projects, such as:

• Deformation analysis (e.g., measuring a tank before and after a pressure test),
• Accident scene surveying to capture conditions with centimeter accuracy,
• Archaeological site documentation during excavation.

What measuring tools are used?

Indoor mobile scanner

Used for detailed surveys of very (really, very) large facilities (e.g., warehouses, office buildings, public institutions).

• Millimeter-accuracy measurement
• Placed on a wheeled, pushable structure that “looks around” room by room
• 10,000-20,000 m²/day can be surveyed
• Records up to 1 million points per second

Static laser scanner

Used for detailed surveys of large facilities, complex building complexes, heritage buildings, intricate mechanical systems, etc., where high precision and detail are required.

• Millimeter-accuracy measurement
• The device is placed on a tripod and “looks around” room by room
• 2-3 minutes per position for the survey
• Records up to 2 million points per second

Handheld mobile scanner

Frequently used for concept creation or interior design when the client expects a quickly visualized, well-founded idea for implementation, or where there’s no space for static scanning.

• 5-8 mm accuracy per room
• Carried in hand, measures while moving, route tracked via smartphone
• Thousands of m²/day can be surveyed (continuous measurement)
• Records 100,000-200,000 points per second

Drone-mounted scanner

Used to survey large areas, building complexes, or structures that are difficult or risky to reach.

• Centimeter-accuracy measurement
• The scanner is mounted on a drone, which flies over and scans the target area
• Covers several km² in a single flight
• Records several hundred thousand points per second

Photogrammetry (not a scanner)

• Centimeter-accuracy measurement
• Measurement is done via photos
• Covers several hectares in a single flight
• Offers resolution greater than 1 cm

This is the fastest data collection method and is used in similar areas as drone scanners, but with lower investment needs. It can produce digital orthophotos and point clouds for calculating earth volumes, creating concepts, roof surveys, and surface modeling for visualizations.

What are the advantages of Scan to BIM?

In one sentence: We can create plans that are almost as accurate as those for greenfield projects, even after construction is complete.

The technology allows us to bring the (built) reality into the digital space and enrich it with building information, paving the way for a BIM model-based operational system.

Compared to traditional survey methods:

Many say that scan to BIM technology has given BIM a new lease of life, because laser scanning has brought reality to what was previously more of a theory – and there is something to that!