Is my IFC file uploaded anywhere?

No. Files are parsed entirely in your browser via web-ifc, a WebAssembly build of the open-source IFC parser. Nothing leaves your machine. The app works completely offline once loaded.

Can I use it with confidential models under NDA?

Yes. Because all processing happens in your browser and no data is ever transmitted to any server, you can safely use it with confidential project models under NDA. There is no service agreement to review with your client — no data changes hands.

Can I share the validation results with my team or client?

Yes. After running validation, click Share Report to copy a link that encodes the full Health Score and issue list directly in the URL — no file upload, no server, no account required. You can also export results as JSON, CSV, or a Validation Certificate. The IFC file itself never leaves your browser.

Yes, fully. IFC Viewer Online works on any modern browser — Chrome, Edge, Firefox, and Safari on both Mac and Windows. No plugin, no installation, no operating system restriction.

What happens if my IFC file is very large?

The app handles files up to 2 GB. Performance depends on your device — files under 200 MB load well on most modern hardware. Once parsed, geometry is cached in OPFS so every subsequent load of the same file is instant, even offline.

How does the validation work?

The validator runs 44 built-in rules in a background Web Worker so the UI stays responsive. Rules cover GUID duplicates, spatial hierarchy, orphan elements, naming conventions, missing type assignments, ISO 19650 property sets, LOD completeness, clash detection, proxy overuse, coordinate offset, storey-elevation integrity, unit consistency, and more. You can also run a buildingSMART IDS specification against the model. Every model receives a Health Score from 0 to 100. Results stream in as each rule completes.

Can I fix errors and re-export a corrected IFC?

Yes. All edits (GUID fixes, renames, property value changes) are held as non-destructive diffs with full undo/redo. Clicking Export IFC applies all diffs to the original binary in a Web Worker and downloads the corrected file — no server involved.

What IFC versions are supported?

IFC2x3, IFC4, IFC4x1, and IFC4x3. The viewer uses the open-source web-ifc parser — the same engine used by most modern BIM tools and @thatopen/components. Outdated schemas are automatically flagged by the validator.

What measurement tools are available?

You can measure lengths between any two points, areas of surfaces, volumes of enclosed elements, and individual edge lengths — all directly in the 3D viewport. Measurements persist as labelled annotations and can be exported alongside your model.

Can I load multiple IFC files at once?

Yes. Load as many IFC files as your device memory allows. Each model has independent visibility, transforms, validation, quantity takeoff, and export. Use the Scene panel to manage, reorder, or remove models at any time.

Does it work offline?

Yes, once the page is loaded. The WebAssembly parser and WebGL renderer run entirely in the browser. Parsed geometry is cached in OPFS so repeat loads are instant even without a network connection.

What are the file size limits?

There is no enforced limit — performance depends on your device. Files up to ~200 MB typically load well on modern hardware. The OPFS geometry cache means you only pay the parse cost once per file.

Is it free? Can I use it for commercial projects?

Yes, completely free. The source code is MIT-licensed. You can use the live app or fork the repository for your own projects, including commercial ones.

Can a browser display IFC and a point cloud together?

Yes. A WebGL viewer can parse IFC geometry and point-cloud formats such as LAS, LAZ, COPC, PLY, PCD or XYZ, then render both in one local coordinate frame. The difficult part is not drawing them; it is proving units, axes and alignment.

Does matching bounding boxes prove Scan-to-BIM alignment?

No. Similar bounds are only evidence for an initial placement. Trustworthy alignment comes from a shared CRS or a documented transform validated against control points or model surfaces.

Is the live example a measured survey?

The inline live example uses a synthetic, georeferenced Poblenou site scan so it loads quickly and deterministically. The article screenshots also show the real CRAS Labs Scan-vs-BIM dataset and identify its source.

Back to the BIM & IFC blog

Digital Twins · 2026-08-21 · 11 min

IFC Point Cloud Viewer: Real Scan-to-BIM Case + Browser Demo

See a real CRAS TLS-to-IFC alignment, inspect sections and launch an interactive IFC + LAS browser demo with no model upload.

IFC Point Cloud Viewer: Real Scan-to-BIM Case + Browser Demo — IFC Viewer Online

Putting an IFC model and a point cloud in the same WebGL scene is visually impressive. Making the comparison defensible is a different job. A useful Scan-to-BIM viewer has to preserve source units, identify the up axis, resolve coordinate systems, expose any manual transform and keep enough points on screen to reveal deviations without exhausting the GPU.

This guide separates those concerns. The live example below uses a small synthetic pair for a fast exhibition experience; the validation images use a real terrestrial laser scanning dataset so that a concept illustration is never presented as survey evidence.

7 — supported point formats
999491 — points in the CRAS web sample
3 — alignment confidence levels
0 uploads — required for local files

Try IFC + a Point Cloud Live

Start the example to load a lightweight IFC4 pavilion and its matching LAS survey in the real viewer. Orbit the scene, inspect the overlay and open the full viewer if you want the complete point-cloud controls. This pair is synthetic and uses a shared ETRS89 / UTM 31N reference; it demonstrates the workflow, not the accuracy of a physical instrument.

Poblenou Pavilion — IFC + LAS overlay

Interactive browser example using a bundled IFC4 pavilion and a 150,000-point synthetic site survey with a shared projected CRS.

Real CRAS TLS point cloud aligned with its IFC model, used as the preview for the interactive workflow — IFC and LAS are ready — drag to orbit

What Alignment Actually Means

IFC can declare a projected coordinate reference through map conversion data. A point cloud may carry an EPSG code, local survey coordinates or no reference at all. When both sources declare the same CRS, placement can be exact in the mathematical sense. When they do not, the viewer needs a documented transform and must label its confidence. The buildingSMART IfcMapConversion definition describes the coordinate operation on the IFC side.

Alignment rung	Evidence	What the UI should say
Exact	Common declared CRS and valid map conversion	Aligned by shared coordinate reference
Inferred	Compatible units, axes and geometry bounds	Probable placement — verify against control
Manual	User translation, rotation and scale	Placed manually — not survey control

A confidence label prevents a convenient visual overlay from being mistaken for surveyed truth.

Perspective view of the CRAS Labs coloured point cloud aligned with translucent IFC walls, doors and windows — Real Scan-vs-BIM alignment: the CRAS Labs TLS web sample over the unmodified IFC model.

A Browser Pipeline That Survives Large Scans

The browser should never assume that file size equals resident GPU size. Headers are inspected before allocating. The parser applies a point budget, workers keep decoding off the UI thread, and the renderer stores only the attributes the current display mode needs. For spatially indexed COPC or 3D Tiles, the camera selects visible nodes instead of downloading the whole survey.

OGC describes 3D Tiles as a hierarchical standard for streaming massive geospatial content including BIM/CAD and point clouds. That hierarchy is the important idea: screen-space error and view selection decide what to load. See the official OGC 3D Tiles overview.

Keep a local origin

Global coordinates stay in Float64 metadata; GPU vertices remain small local values to avoid visible jitter.

Budget points, not files

A declared count and a resident count are different facts. Show both when sampling or truncation occurs.

Reuse GPU attributes

RGB, intensity, classification and deviation views should share buffers instead of cloning the cloud.

Stream indexed formats

COPC or tiled data lets the camera request spatial nodes while a plain LAS file remains a one-shot decode.

Section view cutting through an IFC model and its registered point cloud to compare wall and ceiling surfaces — A section makes offsets easier to inspect than an attractive perspective view.

How to Present It at a Fair

Begin with IFC only so the audience understands the designed geometry.
Reveal the scan at medium opacity and explain the alignment confidence before discussing deviations.
Switch to a section or deviation colour mode; do not rely only on a photogenic perspective.
Pick one point and show source coordinates, classification and distance to make the scene operational.
Finish by loading the offline bundled example again: a repeatable demo is more persuasive than venue Wi-Fi.

The same viewer can also handle time rather than only space. Continue with the real-time LiDAR architecture and MCAP replay guide, or add visual project evidence with IFC video placed on 3D terrain.

IFC Point Cloud Viewer: Real Scan-to-BIM Case + Browser Demo