Use case
Scan to BIM for renovation and retrofit
Renovation design is only as good as its existing-conditions survey. Scan to BIM gives architects and engineers a measured starting point. Here is how to use it from feasibility to handover.
Why scan before you renovate
Old buildings are rarely as drawn. Walls are out of plumb, floors are not level, and decades of alterations have moved things around. Designing against drawings that are wrong leads to redesign, variations and delays. A measured model removes the guesswork, and becomes the base for the design, the planning drawings and the record of the finished work.
When to scan
- Feasibility: a quick, lower-LOD model to test options. Even a phone scan can help for small spaces (see Scan to BIM with an iPhone).
- Design: a full existing-conditions model at LOD 300.
- After strip-out: a second scan once finishes are removed reveals structure and services hidden before.
- Completion: an as-built scan to verify and record the finished work.
What to model
| Element | Suggested LOD | Notes |
|---|---|---|
| Walls, floors, roofs | 300 | Model real thickness and out-of-plumb where it matters |
| Doors, windows, openings | 300 | Sizes, sill and head heights |
| Structure | 300 | Visible members; flag inferred ones |
| Services | 300 to 350 | See Scan to BIM for MEP |
| Heritage features | Mesh or 400 | Mouldings and ornament as measured meshes, not families |
Existing and new in one model
In Revit, put the scanned elements on an "Existing" phase and design on a "New Construction" phase. Demolition is shown by setting elements to be demolished in the new phase. This keeps the survey intact and produces existing, demolition and proposed drawings from one model. Ask for this in the specification (see how to write a Scan to BIM specification).
Irregular geometry
Should a wall that leans 20 mm be modeled leaning? Usually no for design work, yes where fit matters. Decide per element and set the LOA accordingly. The deviation analysis (see QA against the point cloud) will show where the simplification exceeds tolerance.
Historic buildings
Scans are an excellent record of historic fabric. Ornamental elements are best kept as measured meshes linked to simple BIM elements, so the model stays light while the record stays accurate.
Energy retrofits
For envelope upgrades, the scan gives exact facade areas, window sizes and roof geometry for energy models and for ordering insulation and glazing. Pairing the model with thermal imaging helps locate weak spots.
Getting the model fast
Renovation programmes are tight. With Moving Atoms you upload a scan and receive a separated Revit and IFC model within 48 hours, so design can start the same week. For pricing context see the Scan to BIM cost guide.
Have a scan? Send it to us and get separated, editable Revit and IFC objects back within 48 hours.
Frequently asked questions
Why use Scan to BIM for renovation?
Existing buildings are rarely as drawn. A measured model avoids designing against wrong drawings, reducing redesign and site variations.
How do I show existing and new in Revit?
Model the scanned elements on an Existing phase and the design on a New Construction phase, using phase filters for existing, demolition and proposed views.