Specification template · no email gate
Scan-to-BIM LOD, LOI and tolerance matrix
Use this matrix before requesting prices. It separates geometric development, information requirements, modelling tolerance, visibility, quality checks, and acceptance so vendors quote the same outcome.
What should the reference matrix contain?
| Element class | Illustrative LOD/LOI | Tolerance discussion | QA and exceptions |
|---|---|---|---|
| Primary structure, slabs and cores | LOD 300-350; material and member identity where required | Often ±5-10 mm when the registered scan supports it | Check grids, levels, primary faces and critical interfaces |
| Architectural walls and openings | LOD 300; type, thickness and room/space data as specified | Often ±5-15 mm; critical openings may need full checks | Record concealed build-ups and obstructed areas |
| Main duct and pipe routes | LOD 300-350; system and size where visible/authorized | Define centreline or outside-surface measurement | Prioritize clearances, slopes, access and crossings |
| Small-bore, flexible and temporary services | LOD 200 or excluded unless operationally important | Avoid implying fabrication accuracy from sparse/noisy data | State size threshold and visibility rule |
| Equipment | LOD 300; identity and maintainable parameters by need | Verify connection and clearance-critical faces | Separate generic envelope from custom family detail |
| Field-verified record requirements | Do not label LOD 500 without a defined verification basis | Set element, method, sample, date and authority | Retain evidence and accepted exceptions |
Which fields should you copy into an RFP?
- Element or system and project zone.
- Required model use and authoring/exchange format.
- LOD and required non-graphic information.
- Source point cloud and coordinate basis.
- Critical geometry and agreed tolerance.
- Occlusion, minimum visible size, assumptions, and exclusions.
- QA method, sample size, evidence, acceptance owner, and correction period.
What is the most important LOD warning?
LOD is not a universal accuracy value. A detailed-looking family can still be misplaced, and a geometrically accurate envelope can carry little information. Define reliability, tolerance, LOI, and verification separately from visual detail.
Request the editable matrix
The reference table above is available without an email gate. If you want an editable version and a project-specific review, submit your details below.