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 Outdated schemas are automatically flagged by the validator.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 an MP4 be placed inside a Three.js IFC scene?

Yes. An HTMLVideoElement can drive a VideoTexture applied to a plane in the same scene as the IFC model. The application must own and dispose the media element, texture, material and geometry.

Which video placement mode works best at a trade fair?

A camera-facing billboard is the most robust first view because it remains legible as the presenter moves the camera. Ground overlays provide stronger spatial context but require careful placement and opacity.

Is the Operations Pavilion clip real construction footage?

No. It is a clearly labelled synthetic eight-second loop authored with the matching IFC solely to make the offline exhibition workflow reproducible.

Back to the BIM & IFC blog

Digital Twins · 2026-08-21 · 10 min

IFC + Video on 3D Terrain: Interactive Construction Demo

See the actual viewer place video beside IFC as a screen, terrain overlay or billboard, then try metric position and opacity in the browser demo.

IFC + Video on 3D Terrain: Interactive Construction Demo — IFC Viewer Online

A normal video player explains time but loses space. A normal IFC viewer explains space but often loses the visual evidence captured on site. Putting the two resources in one 3D frame lets a presenter point at the designed element, the terrain context and the recorded condition without switching applications.

The goal is not to drape video everywhere. It is to choose a placement mode that answers a user question: What did this camera see? Where does this progress evidence belong? Which surface or work area is being discussed?

Watch the Offline Example Clip

Operations Pavilion construction progress loop

Synthetic eight-second loop paired with the bundled IFC4 pavilion.

Try IFC + 3D Video Live

Start the live example to load the exact IFC companion, create one video texture and frame both resources together. The clip begins muted and loops locally, so the demo does not depend on a streaming service or exhibition Wi-Fi.

Operations Pavilion — IFC + video texture

Interactive WebGL example using a bundled IFC4 model and its matching synthetic progress loop as a camera-facing 3D resource.

Actual IFC Viewer Online interface showing the pavilion, the video billboard and metric position, size and opacity controls — IFC and video are ready — drag to orbit

IFC Viewer Online showing the Operations Pavilion, a video billboard and controls for screen, terrain, position, width and opacity — Actual product capture: the bundled IFC and MP4 are loaded together and the video surface can be positioned, resized and made transparent.

Three Placement Modes, Three Different Jobs

Comparison of a construction video placed as a vertical screen, a ground-aligned terrain overlay and a camera-facing billboard beside an IFC pavilion — Screen, ground overlay and billboard are presentation choices, not interchangeable visual effects.

Mode	Best use	Main risk
Screen	Inspection station, façade or equipment camera	Looks detached if its 3D position is arbitrary
Ground / terrain	Progress area, drone context, excavation evidence	Z-fighting or false precision on uneven terrain
Billboard	Fairs, guided tours and quick storytelling	Less spatially authoritative because it follows the camera

Opacity and Terrain Are Product Controls

Opacity is useful when the audience needs to see designed geometry through recorded pixels. It is not a decoration slider: at low opacity the video may become impossible to interpret, while at full opacity it can hide the IFC evidence being discussed. A useful default keeps the media legible and offers a one-click comparison state.

A ground video also needs a metric width, local position, yaw and a small surface offset. If the application can sample the visible terrain or scene meshes, it can snap the plane onto the surface. The UI should still expose the resulting placement; an automatic snap is a convenience, not a surveyed transform.

Operations Pavilion IFC model shown with a warm construction progress video frame prepared for placement as a 3D texture — The stable poster is used by the player, social metadata and video search markup.

Performance and Lifecycle Rules

Create the HTMLVideoElement and WebGL VideoTexture only after a user opens the example or the resource enters the viewport.
Reuse one texture while changing opacity or placement; do not recreate the decoder for every slider movement.
Pause video when hidden, and dispose the media element, texture, material, geometry and object URL when removed.
Keep a static poster in the page so users and crawlers have useful content before WebGL starts.
Prefer a small local MP4/WebM loop for fairs, then add WebRTC camera or screen capture as an explicitly live source.

A Five-Minute Fair Narrative

Open the IFC alone and frame the pavilion.
Load the matching clip as a billboard so every attendee can see it immediately.
Switch to ground mode and adjust opacity to reveal the spatial relationship.
Move the camera while the clip continues, demonstrating that it is part of the 3D scene rather than an overlay on the webpage.
End by loading the same pair offline again and explain how a real camera, shared screen or recorded inspection could replace the synthetic source.

If the evidence must remain inspectable as XYZ points rather than pixels, use the temporal LiDAR and MCAP architecture. If the comparison is static and measured, start with IFC + point-cloud Scan-to-BIM alignment.

IFC + Video on 3D Terrain: Interactive Construction Demo